diff options
Diffstat (limited to 'contrib/qemu/block.c')
| -rw-r--r-- | contrib/qemu/block.c | 4604 |
1 files changed, 0 insertions, 4604 deletions
diff --git a/contrib/qemu/block.c b/contrib/qemu/block.c deleted file mode 100644 index b56024113b8..00000000000 --- a/contrib/qemu/block.c +++ /dev/null @@ -1,4604 +0,0 @@ -/* - * QEMU System Emulator block driver - * - * Copyright (c) 2003 Fabrice Bellard - * - * Permission is hereby granted, free of charge, to any person obtaining a copy - * of this software and associated documentation files (the "Software"), to deal - * in the Software without restriction, including without limitation the rights - * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell - * copies of the Software, and to permit persons to whom the Software is - * furnished to do so, subject to the following conditions: - * - * The above copyright notice and this permission notice shall be included in - * all copies or substantial portions of the Software. - * - * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR - * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, - * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL - * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER - * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, - * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN - * THE SOFTWARE. - */ -#include "config-host.h" -#include "qemu-common.h" -#include "trace.h" -#include "monitor/monitor.h" -#include "block/block_int.h" -#include "block/blockjob.h" -#include "qemu/module.h" -#include "qapi/qmp/qjson.h" -#include "sysemu/sysemu.h" -#include "qemu/notify.h" -#include "block/coroutine.h" -#include "qmp-commands.h" -#include "qemu/timer.h" - -#ifdef CONFIG_BSD -#include <sys/types.h> -#include <sys/stat.h> -#include <sys/ioctl.h> -#include <sys/queue.h> -#ifndef __DragonFly__ -#include <sys/disk.h> -#endif -#endif - -#ifdef _WIN32 -#include <windows.h> -#endif - -#define NOT_DONE 0x7fffffff /* used while emulated sync operation in progress */ - -typedef enum { - BDRV_REQ_COPY_ON_READ = 0x1, - BDRV_REQ_ZERO_WRITE = 0x2, -} BdrvRequestFlags; - -static void bdrv_dev_change_media_cb(BlockDriverState *bs, bool load); -static BlockDriverAIOCB *bdrv_aio_readv_em(BlockDriverState *bs, - int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, - BlockDriverCompletionFunc *cb, void *opaque); -static BlockDriverAIOCB *bdrv_aio_writev_em(BlockDriverState *bs, - int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, - BlockDriverCompletionFunc *cb, void *opaque); -static int coroutine_fn bdrv_co_readv_em(BlockDriverState *bs, - int64_t sector_num, int nb_sectors, - QEMUIOVector *iov); -static int coroutine_fn bdrv_co_writev_em(BlockDriverState *bs, - int64_t sector_num, int nb_sectors, - QEMUIOVector *iov); -static int coroutine_fn bdrv_co_do_readv(BlockDriverState *bs, - int64_t sector_num, int nb_sectors, QEMUIOVector *qiov, - BdrvRequestFlags flags); -static int coroutine_fn bdrv_co_do_writev(BlockDriverState *bs, - int64_t sector_num, int nb_sectors, QEMUIOVector *qiov, - BdrvRequestFlags flags); -static BlockDriverAIOCB *bdrv_co_aio_rw_vector(BlockDriverState *bs, - int64_t sector_num, - QEMUIOVector *qiov, - int nb_sectors, - BlockDriverCompletionFunc *cb, - void *opaque, - bool is_write); -static void coroutine_fn bdrv_co_do_rw(void *opaque); -static int coroutine_fn bdrv_co_do_write_zeroes(BlockDriverState *bs, - int64_t sector_num, int nb_sectors); - -static bool bdrv_exceed_bps_limits(BlockDriverState *bs, int nb_sectors, - bool is_write, double elapsed_time, uint64_t *wait); -static bool bdrv_exceed_iops_limits(BlockDriverState *bs, bool is_write, - double elapsed_time, uint64_t *wait); -static bool bdrv_exceed_io_limits(BlockDriverState *bs, int nb_sectors, - bool is_write, int64_t *wait); - -static QTAILQ_HEAD(, BlockDriverState) bdrv_states = - QTAILQ_HEAD_INITIALIZER(bdrv_states); - -static QLIST_HEAD(, BlockDriver) bdrv_drivers = - QLIST_HEAD_INITIALIZER(bdrv_drivers); - -/* If non-zero, use only whitelisted block drivers */ -static int use_bdrv_whitelist; - -#ifdef _WIN32 -static int is_windows_drive_prefix(const char *filename) -{ - return (((filename[0] >= 'a' && filename[0] <= 'z') || - (filename[0] >= 'A' && filename[0] <= 'Z')) && - filename[1] == ':'); -} - -int is_windows_drive(const char *filename) -{ - if (is_windows_drive_prefix(filename) && - filename[2] == '\0') - return 1; - if (strstart(filename, "\\\\.\\", NULL) || - strstart(filename, "//./", NULL)) - return 1; - return 0; -} -#endif - -/* throttling disk I/O limits */ -void bdrv_io_limits_disable(BlockDriverState *bs) -{ - bs->io_limits_enabled = false; - - while (qemu_co_queue_next(&bs->throttled_reqs)); - - if (bs->block_timer) { - qemu_del_timer(bs->block_timer); - qemu_free_timer(bs->block_timer); - bs->block_timer = NULL; - } - - bs->slice_start = 0; - bs->slice_end = 0; -} - -static void bdrv_block_timer(void *opaque) -{ - BlockDriverState *bs = opaque; - - qemu_co_queue_next(&bs->throttled_reqs); -} - -void bdrv_io_limits_enable(BlockDriverState *bs) -{ - qemu_co_queue_init(&bs->throttled_reqs); - bs->block_timer = qemu_new_timer_ns(vm_clock, bdrv_block_timer, bs); - bs->io_limits_enabled = true; -} - -bool bdrv_io_limits_enabled(BlockDriverState *bs) -{ - BlockIOLimit *io_limits = &bs->io_limits; - return io_limits->bps[BLOCK_IO_LIMIT_READ] - || io_limits->bps[BLOCK_IO_LIMIT_WRITE] - || io_limits->bps[BLOCK_IO_LIMIT_TOTAL] - || io_limits->iops[BLOCK_IO_LIMIT_READ] - || io_limits->iops[BLOCK_IO_LIMIT_WRITE] - || io_limits->iops[BLOCK_IO_LIMIT_TOTAL]; -} - -static void bdrv_io_limits_intercept(BlockDriverState *bs, - bool is_write, int nb_sectors) -{ - int64_t wait_time = -1; - - if (!qemu_co_queue_empty(&bs->throttled_reqs)) { - qemu_co_queue_wait(&bs->throttled_reqs); - } - - /* In fact, we hope to keep each request's timing, in FIFO mode. The next - * throttled requests will not be dequeued until the current request is - * allowed to be serviced. So if the current request still exceeds the - * limits, it will be inserted to the head. All requests followed it will - * be still in throttled_reqs queue. - */ - - while (bdrv_exceed_io_limits(bs, nb_sectors, is_write, &wait_time)) { - qemu_mod_timer(bs->block_timer, - wait_time + qemu_get_clock_ns(vm_clock)); - qemu_co_queue_wait_insert_head(&bs->throttled_reqs); - } - - qemu_co_queue_next(&bs->throttled_reqs); -} - -/* check if the path starts with "<protocol>:" */ -static int path_has_protocol(const char *path) -{ - const char *p; - -#ifdef _WIN32 - if (is_windows_drive(path) || - is_windows_drive_prefix(path)) { - return 0; - } - p = path + strcspn(path, ":/\\"); -#else - p = path + strcspn(path, ":/"); -#endif - - return *p == ':'; -} - -int path_is_absolute(const char *path) -{ -#ifdef _WIN32 - /* specific case for names like: "\\.\d:" */ - if (is_windows_drive(path) || is_windows_drive_prefix(path)) { - return 1; - } - return (*path == '/' || *path == '\\'); -#else - return (*path == '/'); -#endif -} - -/* if filename is absolute, just copy it to dest. Otherwise, build a - path to it by considering it is relative to base_path. URL are - supported. */ -void path_combine(char *dest, int dest_size, - const char *base_path, - const char *filename) -{ - const char *p, *p1; - int len; - - if (dest_size <= 0) - return; - if (path_is_absolute(filename)) { - pstrcpy(dest, dest_size, filename); - } else { - p = strchr(base_path, ':'); - if (p) - p++; - else - p = base_path; - p1 = strrchr(base_path, '/'); -#ifdef _WIN32 - { - const char *p2; - p2 = strrchr(base_path, '\\'); - if (!p1 || p2 > p1) - p1 = p2; - } -#endif - if (p1) - p1++; - else - p1 = base_path; - if (p1 > p) - p = p1; - len = p - base_path; - if (len > dest_size - 1) - len = dest_size - 1; - memcpy(dest, base_path, len); - dest[len] = '\0'; - pstrcat(dest, dest_size, filename); - } -} - -void bdrv_get_full_backing_filename(BlockDriverState *bs, char *dest, size_t sz) -{ - if (bs->backing_file[0] == '\0' || path_has_protocol(bs->backing_file)) { - pstrcpy(dest, sz, bs->backing_file); - } else { - path_combine(dest, sz, bs->filename, bs->backing_file); - } -} - -void bdrv_register(BlockDriver *bdrv) -{ - /* Block drivers without coroutine functions need emulation */ - if (!bdrv->bdrv_co_readv) { - bdrv->bdrv_co_readv = bdrv_co_readv_em; - bdrv->bdrv_co_writev = bdrv_co_writev_em; - - /* bdrv_co_readv_em()/brdv_co_writev_em() work in terms of aio, so if - * the block driver lacks aio we need to emulate that too. - */ - if (!bdrv->bdrv_aio_readv) { - /* add AIO emulation layer */ - bdrv->bdrv_aio_readv = bdrv_aio_readv_em; - bdrv->bdrv_aio_writev = bdrv_aio_writev_em; - } - } - - QLIST_INSERT_HEAD(&bdrv_drivers, bdrv, list); -} - -/* create a new block device (by default it is empty) */ -BlockDriverState *bdrv_new(const char *device_name) -{ - BlockDriverState *bs; - - bs = g_malloc0(sizeof(BlockDriverState)); - pstrcpy(bs->device_name, sizeof(bs->device_name), device_name); - if (device_name[0] != '\0') { - QTAILQ_INSERT_TAIL(&bdrv_states, bs, list); - } - bdrv_iostatus_disable(bs); - notifier_list_init(&bs->close_notifiers); - notifier_with_return_list_init(&bs->before_write_notifiers); - - return bs; -} - -void bdrv_add_close_notifier(BlockDriverState *bs, Notifier *notify) -{ - notifier_list_add(&bs->close_notifiers, notify); -} - -BlockDriver *bdrv_find_format(const char *format_name) -{ - BlockDriver *drv1; - QLIST_FOREACH(drv1, &bdrv_drivers, list) { - if (!strcmp(drv1->format_name, format_name)) { - return drv1; - } - } - return NULL; -} - -static int bdrv_is_whitelisted(BlockDriver *drv, bool read_only) -{ - static const char *whitelist_rw[] = { - CONFIG_BDRV_RW_WHITELIST - }; - static const char *whitelist_ro[] = { - CONFIG_BDRV_RO_WHITELIST - }; - const char **p; - - if (!whitelist_rw[0] && !whitelist_ro[0]) { - return 1; /* no whitelist, anything goes */ - } - - for (p = whitelist_rw; *p; p++) { - if (!strcmp(drv->format_name, *p)) { - return 1; - } - } - if (read_only) { - for (p = whitelist_ro; *p; p++) { - if (!strcmp(drv->format_name, *p)) { - return 1; - } - } - } - return 0; -} - -BlockDriver *bdrv_find_whitelisted_format(const char *format_name, - bool read_only) -{ - BlockDriver *drv = bdrv_find_format(format_name); - return drv && bdrv_is_whitelisted(drv, read_only) ? drv : NULL; -} - -typedef struct CreateCo { - BlockDriver *drv; - char *filename; - QEMUOptionParameter *options; - int ret; -} CreateCo; - -static void coroutine_fn bdrv_create_co_entry(void *opaque) -{ - CreateCo *cco = opaque; - assert(cco->drv); - - cco->ret = cco->drv->bdrv_create(cco->filename, cco->options); -} - -int bdrv_create(BlockDriver *drv, const char* filename, - QEMUOptionParameter *options) -{ - int ret; - - Coroutine *co; - CreateCo cco = { - .drv = drv, - .filename = g_strdup(filename), - .options = options, - .ret = NOT_DONE, - }; - - if (!drv->bdrv_create) { - ret = -ENOTSUP; - goto out; - } - - if (qemu_in_coroutine()) { - /* Fast-path if already in coroutine context */ - bdrv_create_co_entry(&cco); - } else { - co = qemu_coroutine_create(bdrv_create_co_entry); - qemu_coroutine_enter(co, &cco); - while (cco.ret == NOT_DONE) { - qemu_aio_wait(); - } - } - - ret = cco.ret; - -out: - g_free(cco.filename); - return ret; -} - -int bdrv_create_file(const char* filename, QEMUOptionParameter *options) -{ - BlockDriver *drv; - - drv = bdrv_find_protocol(filename, true); - if (drv == NULL) { - return -ENOENT; - } - - return bdrv_create(drv, filename, options); -} - -/* - * Create a uniquely-named empty temporary file. - * Return 0 upon success, otherwise a negative errno value. - */ -int get_tmp_filename(char *filename, int size) -{ -#ifdef _WIN32 - char temp_dir[MAX_PATH]; - /* GetTempFileName requires that its output buffer (4th param) - have length MAX_PATH or greater. */ - assert(size >= MAX_PATH); - return (GetTempPath(MAX_PATH, temp_dir) - && GetTempFileName(temp_dir, "qem", 0, filename) - ? 0 : -GetLastError()); -#else - int fd; - const char *tmpdir; - tmpdir = getenv("TMPDIR"); - if (!tmpdir) - tmpdir = "/tmp"; - if (snprintf(filename, size, "%s/vl.XXXXXX", tmpdir) >= size) { - return -EOVERFLOW; - } - fd = mkstemp(filename); - if (fd < 0) { - return -errno; - } - if (close(fd) != 0) { - unlink(filename); - return -errno; - } - return 0; -#endif -} - -/* - * Detect host devices. By convention, /dev/cdrom[N] is always - * recognized as a host CDROM. - */ -static BlockDriver *find_hdev_driver(const char *filename) -{ - int score_max = 0, score; - BlockDriver *drv = NULL, *d; - - QLIST_FOREACH(d, &bdrv_drivers, list) { - if (d->bdrv_probe_device) { - score = d->bdrv_probe_device(filename); - if (score > score_max) { - score_max = score; - drv = d; - } - } - } - - return drv; -} - -BlockDriver *bdrv_find_protocol(const char *filename, - bool allow_protocol_prefix) -{ - BlockDriver *drv1; - char protocol[128]; - int len; - const char *p; - - /* TODO Drivers without bdrv_file_open must be specified explicitly */ - - /* - * XXX(hch): we really should not let host device detection - * override an explicit protocol specification, but moving this - * later breaks access to device names with colons in them. - * Thanks to the brain-dead persistent naming schemes on udev- - * based Linux systems those actually are quite common. - */ - drv1 = find_hdev_driver(filename); - if (drv1) { - return drv1; - } - - if (!path_has_protocol(filename) || !allow_protocol_prefix) { - return bdrv_find_format("file"); - } - - p = strchr(filename, ':'); - assert(p != NULL); - len = p - filename; - if (len > sizeof(protocol) - 1) - len = sizeof(protocol) - 1; - memcpy(protocol, filename, len); - protocol[len] = '\0'; - QLIST_FOREACH(drv1, &bdrv_drivers, list) { - if (drv1->protocol_name && - !strcmp(drv1->protocol_name, protocol)) { - return drv1; - } - } - return NULL; -} - -static int find_image_format(BlockDriverState *bs, const char *filename, - BlockDriver **pdrv) -{ - int score, score_max; - BlockDriver *drv1, *drv; - uint8_t buf[2048]; - int ret = 0; - - /* Return the raw BlockDriver * to scsi-generic devices or empty drives */ - if (bs->sg || !bdrv_is_inserted(bs) || bdrv_getlength(bs) == 0) { - drv = bdrv_find_format("raw"); - if (!drv) { - ret = -ENOENT; - } - *pdrv = drv; - return ret; - } - - ret = bdrv_pread(bs, 0, buf, sizeof(buf)); - if (ret < 0) { - *pdrv = NULL; - return ret; - } - - score_max = 0; - drv = NULL; - QLIST_FOREACH(drv1, &bdrv_drivers, list) { - if (drv1->bdrv_probe) { - score = drv1->bdrv_probe(buf, ret, filename); - if (score > score_max) { - score_max = score; - drv = drv1; - } - } - } - if (!drv) { - ret = -ENOENT; - } - *pdrv = drv; - return ret; -} - -/** - * Set the current 'total_sectors' value - */ -static int refresh_total_sectors(BlockDriverState *bs, int64_t hint) -{ - BlockDriver *drv = bs->drv; - - /* Do not attempt drv->bdrv_getlength() on scsi-generic devices */ - if (bs->sg) - return 0; - - /* query actual device if possible, otherwise just trust the hint */ - if (drv->bdrv_getlength) { - int64_t length = drv->bdrv_getlength(bs); - if (length < 0) { - return length; - } - hint = length >> BDRV_SECTOR_BITS; - } - - bs->total_sectors = hint; - return 0; -} - -/** - * Set open flags for a given discard mode - * - * Return 0 on success, -1 if the discard mode was invalid. - */ -int bdrv_parse_discard_flags(const char *mode, int *flags) -{ - *flags &= ~BDRV_O_UNMAP; - - if (!strcmp(mode, "off") || !strcmp(mode, "ignore")) { - /* do nothing */ - } else if (!strcmp(mode, "on") || !strcmp(mode, "unmap")) { - *flags |= BDRV_O_UNMAP; - } else { - return -1; - } - - return 0; -} - -/** - * Set open flags for a given cache mode - * - * Return 0 on success, -1 if the cache mode was invalid. - */ -int bdrv_parse_cache_flags(const char *mode, int *flags) -{ - *flags &= ~BDRV_O_CACHE_MASK; - - if (!strcmp(mode, "off") || !strcmp(mode, "none")) { - *flags |= BDRV_O_NOCACHE | BDRV_O_CACHE_WB; - } else if (!strcmp(mode, "directsync")) { - *flags |= BDRV_O_NOCACHE; - } else if (!strcmp(mode, "writeback")) { - *flags |= BDRV_O_CACHE_WB; - } else if (!strcmp(mode, "unsafe")) { - *flags |= BDRV_O_CACHE_WB; - *flags |= BDRV_O_NO_FLUSH; - } else if (!strcmp(mode, "writethrough")) { - /* this is the default */ - } else { - return -1; - } - - return 0; -} - -/** - * The copy-on-read flag is actually a reference count so multiple users may - * use the feature without worrying about clobbering its previous state. - * Copy-on-read stays enabled until all users have called to disable it. - */ -void bdrv_enable_copy_on_read(BlockDriverState *bs) -{ - bs->copy_on_read++; -} - -void bdrv_disable_copy_on_read(BlockDriverState *bs) -{ - assert(bs->copy_on_read > 0); - bs->copy_on_read--; -} - -static int bdrv_open_flags(BlockDriverState *bs, int flags) -{ - int open_flags = flags | BDRV_O_CACHE_WB; - - /* - * Clear flags that are internal to the block layer before opening the - * image. - */ - open_flags &= ~(BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING); - - /* - * Snapshots should be writable. - */ - if (bs->is_temporary) { - open_flags |= BDRV_O_RDWR; - } - - return open_flags; -} - -/* - * Common part for opening disk images and files - * - * Removes all processed options from *options. - */ -static int bdrv_open_common(BlockDriverState *bs, BlockDriverState *file, - QDict *options, int flags, BlockDriver *drv) -{ - int ret, open_flags; - const char *filename; - - assert(drv != NULL); - assert(bs->file == NULL); - assert(options != NULL && bs->options != options); - - if (file != NULL) { - filename = file->filename; - } else { - filename = qdict_get_try_str(options, "filename"); - } - - trace_bdrv_open_common(bs, filename ?: "", flags, drv->format_name); - - /* bdrv_open() with directly using a protocol as drv. This layer is already - * opened, so assign it to bs (while file becomes a closed BlockDriverState) - * and return immediately. */ - if (file != NULL && drv->bdrv_file_open) { - bdrv_swap(file, bs); - return 0; - } - - bs->open_flags = flags; - bs->buffer_alignment = 512; - open_flags = bdrv_open_flags(bs, flags); - bs->read_only = !(open_flags & BDRV_O_RDWR); - - if (use_bdrv_whitelist && !bdrv_is_whitelisted(drv, bs->read_only)) { - return -ENOTSUP; - } - - assert(bs->copy_on_read == 0); /* bdrv_new() and bdrv_close() make it so */ - if (!bs->read_only && (flags & BDRV_O_COPY_ON_READ)) { - bdrv_enable_copy_on_read(bs); - } - - if (filename != NULL) { - pstrcpy(bs->filename, sizeof(bs->filename), filename); - } else { - bs->filename[0] = '\0'; - } - - bs->drv = drv; - bs->opaque = g_malloc0(drv->instance_size); - - bs->enable_write_cache = !!(flags & BDRV_O_CACHE_WB); - - /* Open the image, either directly or using a protocol */ - if (drv->bdrv_file_open) { - assert(file == NULL); - assert(drv->bdrv_parse_filename || filename != NULL); - ret = drv->bdrv_file_open(bs, options, open_flags); - } else { - if (file == NULL) { - qerror_report(ERROR_CLASS_GENERIC_ERROR, "Can't use '%s' as a " - "block driver for the protocol level", - drv->format_name); - ret = -EINVAL; - goto free_and_fail; - } - assert(file != NULL); - bs->file = file; - ret = drv->bdrv_open(bs, options, open_flags); - } - - if (ret < 0) { - goto free_and_fail; - } - - ret = refresh_total_sectors(bs, bs->total_sectors); - if (ret < 0) { - goto free_and_fail; - } - -#ifndef _WIN32 - if (bs->is_temporary) { - assert(filename != NULL); - unlink(filename); - } -#endif - return 0; - -free_and_fail: - bs->file = NULL; - g_free(bs->opaque); - bs->opaque = NULL; - bs->drv = NULL; - return ret; -} - -/* - * Opens a file using a protocol (file, host_device, nbd, ...) - * - * options is a QDict of options to pass to the block drivers, or NULL for an - * empty set of options. The reference to the QDict belongs to the block layer - * after the call (even on failure), so if the caller intends to reuse the - * dictionary, it needs to use QINCREF() before calling bdrv_file_open. - */ -int bdrv_file_open(BlockDriverState **pbs, const char *filename, - QDict *options, int flags) -{ - BlockDriverState *bs; - BlockDriver *drv; - const char *drvname; - bool allow_protocol_prefix = false; - int ret; - - /* NULL means an empty set of options */ - if (options == NULL) { - options = qdict_new(); - } - - bs = bdrv_new(""); - bs->options = options; - options = qdict_clone_shallow(options); - - /* Fetch the file name from the options QDict if necessary */ - if (!filename) { - filename = qdict_get_try_str(options, "filename"); - } else if (filename && !qdict_haskey(options, "filename")) { - qdict_put(options, "filename", qstring_from_str(filename)); - allow_protocol_prefix = true; - } else { - qerror_report(ERROR_CLASS_GENERIC_ERROR, "Can't specify 'file' and " - "'filename' options at the same time"); - ret = -EINVAL; - goto fail; - } - - /* Find the right block driver */ - drvname = qdict_get_try_str(options, "driver"); - if (drvname) { - drv = bdrv_find_whitelisted_format(drvname, !(flags & BDRV_O_RDWR)); - qdict_del(options, "driver"); - } else if (filename) { - drv = bdrv_find_protocol(filename, allow_protocol_prefix); - if (!drv) { - qerror_report(ERROR_CLASS_GENERIC_ERROR, "Unknown protocol"); - } - } else { - qerror_report(ERROR_CLASS_GENERIC_ERROR, - "Must specify either driver or file"); - drv = NULL; - } - - if (!drv) { - ret = -ENOENT; - goto fail; - } - - /* Parse the filename and open it */ - if (drv->bdrv_parse_filename && filename) { - Error *local_err = NULL; - drv->bdrv_parse_filename(filename, options, &local_err); - if (error_is_set(&local_err)) { - qerror_report_err(local_err); - error_free(local_err); - ret = -EINVAL; - goto fail; - } - qdict_del(options, "filename"); - } else if (!drv->bdrv_parse_filename && !filename) { - qerror_report(ERROR_CLASS_GENERIC_ERROR, - "The '%s' block driver requires a file name", - drv->format_name); - ret = -EINVAL; - goto fail; - } - - ret = bdrv_open_common(bs, NULL, options, flags, drv); - if (ret < 0) { - goto fail; - } - - /* Check if any unknown options were used */ - if (qdict_size(options) != 0) { - const QDictEntry *entry = qdict_first(options); - qerror_report(ERROR_CLASS_GENERIC_ERROR, "Block protocol '%s' doesn't " - "support the option '%s'", - drv->format_name, entry->key); - ret = -EINVAL; - goto fail; - } - QDECREF(options); - - bs->growable = 1; - *pbs = bs; - return 0; - -fail: - QDECREF(options); - if (!bs->drv) { - QDECREF(bs->options); - } - bdrv_delete(bs); - return ret; -} - -/* - * Opens the backing file for a BlockDriverState if not yet open - * - * options is a QDict of options to pass to the block drivers, or NULL for an - * empty set of options. The reference to the QDict is transferred to this - * function (even on failure), so if the caller intends to reuse the dictionary, - * it needs to use QINCREF() before calling bdrv_file_open. - */ -int bdrv_open_backing_file(BlockDriverState *bs, QDict *options) -{ - char backing_filename[PATH_MAX]; - int back_flags, ret; - BlockDriver *back_drv = NULL; - - if (bs->backing_hd != NULL) { - QDECREF(options); - return 0; - } - - /* NULL means an empty set of options */ - if (options == NULL) { - options = qdict_new(); - } - - bs->open_flags &= ~BDRV_O_NO_BACKING; - if (qdict_haskey(options, "file.filename")) { - backing_filename[0] = '\0'; - } else if (bs->backing_file[0] == '\0' && qdict_size(options) == 0) { - QDECREF(options); - return 0; - } - - bs->backing_hd = bdrv_new(""); - bdrv_get_full_backing_filename(bs, backing_filename, - sizeof(backing_filename)); - - if (bs->backing_format[0] != '\0') { - back_drv = bdrv_find_format(bs->backing_format); - } - - /* backing files always opened read-only */ - back_flags = bs->open_flags & ~(BDRV_O_RDWR | BDRV_O_SNAPSHOT); - - ret = bdrv_open(bs->backing_hd, - *backing_filename ? backing_filename : NULL, options, - back_flags, back_drv); - if (ret < 0) { - bdrv_delete(bs->backing_hd); - bs->backing_hd = NULL; - bs->open_flags |= BDRV_O_NO_BACKING; - return ret; - } - return 0; -} - -static void extract_subqdict(QDict *src, QDict **dst, const char *start) -{ - const QDictEntry *entry, *next; - const char *p; - - *dst = qdict_new(); - entry = qdict_first(src); - - while (entry != NULL) { - next = qdict_next(src, entry); - if (strstart(entry->key, start, &p)) { - qobject_incref(entry->value); - qdict_put_obj(*dst, p, entry->value); - qdict_del(src, entry->key); - } - entry = next; - } -} - -/* - * Opens a disk image (raw, qcow2, vmdk, ...) - * - * options is a QDict of options to pass to the block drivers, or NULL for an - * empty set of options. The reference to the QDict belongs to the block layer - * after the call (even on failure), so if the caller intends to reuse the - * dictionary, it needs to use QINCREF() before calling bdrv_open. - */ -int bdrv_open(BlockDriverState *bs, const char *filename, QDict *options, - int flags, BlockDriver *drv) -{ - int ret; - /* TODO: extra byte is a hack to ensure MAX_PATH space on Windows. */ - char tmp_filename[PATH_MAX + 1]; - BlockDriverState *file = NULL; - QDict *file_options = NULL; - - /* NULL means an empty set of options */ - if (options == NULL) { - options = qdict_new(); - } - - bs->options = options; - options = qdict_clone_shallow(options); - - /* For snapshot=on, create a temporary qcow2 overlay */ - if (flags & BDRV_O_SNAPSHOT) { - BlockDriverState *bs1; - int64_t total_size; - BlockDriver *bdrv_qcow2; - QEMUOptionParameter *create_options; - char backing_filename[PATH_MAX]; - - if (qdict_size(options) != 0) { - error_report("Can't use snapshot=on with driver-specific options"); - ret = -EINVAL; - goto fail; - } - assert(filename != NULL); - - /* if snapshot, we create a temporary backing file and open it - instead of opening 'filename' directly */ - - /* if there is a backing file, use it */ - bs1 = bdrv_new(""); - ret = bdrv_open(bs1, filename, NULL, 0, drv); - if (ret < 0) { - bdrv_delete(bs1); - goto fail; - } - total_size = bdrv_getlength(bs1) & BDRV_SECTOR_MASK; - - bdrv_delete(bs1); - - ret = get_tmp_filename(tmp_filename, sizeof(tmp_filename)); - if (ret < 0) { - goto fail; - } - - /* Real path is meaningless for protocols */ - if (path_has_protocol(filename)) { - snprintf(backing_filename, sizeof(backing_filename), - "%s", filename); - } else if (!realpath(filename, backing_filename)) { - ret = -errno; - goto fail; - } - - bdrv_qcow2 = bdrv_find_format("qcow2"); - create_options = parse_option_parameters("", bdrv_qcow2->create_options, - NULL); - - set_option_parameter_int(create_options, BLOCK_OPT_SIZE, total_size); - set_option_parameter(create_options, BLOCK_OPT_BACKING_FILE, - backing_filename); - if (drv) { - set_option_parameter(create_options, BLOCK_OPT_BACKING_FMT, - drv->format_name); - } - - ret = bdrv_create(bdrv_qcow2, tmp_filename, create_options); - free_option_parameters(create_options); - if (ret < 0) { - goto fail; - } - - filename = tmp_filename; - drv = bdrv_qcow2; - bs->is_temporary = 1; - } - - /* Open image file without format layer */ - if (flags & BDRV_O_RDWR) { - flags |= BDRV_O_ALLOW_RDWR; - } - - extract_subqdict(options, &file_options, "file."); - - ret = bdrv_file_open(&file, filename, file_options, - bdrv_open_flags(bs, flags | BDRV_O_UNMAP)); - if (ret < 0) { - goto fail; - } - - /* Find the right image format driver */ - if (!drv) { - ret = find_image_format(file, filename, &drv); - } - - if (!drv) { - goto unlink_and_fail; - } - - /* Open the image */ - ret = bdrv_open_common(bs, file, options, flags, drv); - if (ret < 0) { - goto unlink_and_fail; - } - - if (bs->file != file) { - bdrv_delete(file); - file = NULL; - } - - /* If there is a backing file, use it */ - if ((flags & BDRV_O_NO_BACKING) == 0) { - QDict *backing_options; - - extract_subqdict(options, &backing_options, "backing."); - ret = bdrv_open_backing_file(bs, backing_options); - if (ret < 0) { - goto close_and_fail; - } - } - - /* Check if any unknown options were used */ - if (qdict_size(options) != 0) { - const QDictEntry *entry = qdict_first(options); - qerror_report(ERROR_CLASS_GENERIC_ERROR, "Block format '%s' used by " - "device '%s' doesn't support the option '%s'", - drv->format_name, bs->device_name, entry->key); - - ret = -EINVAL; - goto close_and_fail; - } - QDECREF(options); - - if (!bdrv_key_required(bs)) { - bdrv_dev_change_media_cb(bs, true); - } - - /* throttling disk I/O limits */ - if (bs->io_limits_enabled) { - bdrv_io_limits_enable(bs); - } - - return 0; - -unlink_and_fail: - if (file != NULL) { - bdrv_delete(file); - } - if (bs->is_temporary) { - unlink(filename); - } -fail: - QDECREF(bs->options); - QDECREF(options); - bs->options = NULL; - return ret; - -close_and_fail: - bdrv_close(bs); - QDECREF(options); - return ret; -} - -typedef struct BlockReopenQueueEntry { - bool prepared; - BDRVReopenState state; - QSIMPLEQ_ENTRY(BlockReopenQueueEntry) entry; -} BlockReopenQueueEntry; - -/* - * Adds a BlockDriverState to a simple queue for an atomic, transactional - * reopen of multiple devices. - * - * bs_queue can either be an existing BlockReopenQueue that has had QSIMPLE_INIT - * already performed, or alternatively may be NULL a new BlockReopenQueue will - * be created and initialized. This newly created BlockReopenQueue should be - * passed back in for subsequent calls that are intended to be of the same - * atomic 'set'. - * - * bs is the BlockDriverState to add to the reopen queue. - * - * flags contains the open flags for the associated bs - * - * returns a pointer to bs_queue, which is either the newly allocated - * bs_queue, or the existing bs_queue being used. - * - */ -BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue, - BlockDriverState *bs, int flags) -{ - assert(bs != NULL); - - BlockReopenQueueEntry *bs_entry; - if (bs_queue == NULL) { - bs_queue = g_new0(BlockReopenQueue, 1); - QSIMPLEQ_INIT(bs_queue); - } - - if (bs->file) { - bdrv_reopen_queue(bs_queue, bs->file, flags); - } - - bs_entry = g_new0(BlockReopenQueueEntry, 1); - QSIMPLEQ_INSERT_TAIL(bs_queue, bs_entry, entry); - - bs_entry->state.bs = bs; - bs_entry->state.flags = flags; - - return bs_queue; -} - -/* - * Reopen multiple BlockDriverStates atomically & transactionally. - * - * The queue passed in (bs_queue) must have been built up previous - * via bdrv_reopen_queue(). - * - * Reopens all BDS specified in the queue, with the appropriate - * flags. All devices are prepared for reopen, and failure of any - * device will cause all device changes to be abandonded, and intermediate - * data cleaned up. - * - * If all devices prepare successfully, then the changes are committed - * to all devices. - * - */ -int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp) -{ - int ret = -1; - BlockReopenQueueEntry *bs_entry, *next; - Error *local_err = NULL; - - assert(bs_queue != NULL); - - bdrv_drain_all(); - - QSIMPLEQ_FOREACH(bs_entry, bs_queue, entry) { - if (bdrv_reopen_prepare(&bs_entry->state, bs_queue, &local_err)) { - error_propagate(errp, local_err); - goto cleanup; - } - bs_entry->prepared = true; - } - - /* If we reach this point, we have success and just need to apply the - * changes - */ - QSIMPLEQ_FOREACH(bs_entry, bs_queue, entry) { - bdrv_reopen_commit(&bs_entry->state); - } - - ret = 0; - -cleanup: - QSIMPLEQ_FOREACH_SAFE(bs_entry, bs_queue, entry, next) { - if (ret && bs_entry->prepared) { - bdrv_reopen_abort(&bs_entry->state); - } - g_free(bs_entry); - } - g_free(bs_queue); - return ret; -} - - -/* Reopen a single BlockDriverState with the specified flags. */ -int bdrv_reopen(BlockDriverState *bs, int bdrv_flags, Error **errp) -{ - int ret = -1; - Error *local_err = NULL; - BlockReopenQueue *queue = bdrv_reopen_queue(NULL, bs, bdrv_flags); - - ret = bdrv_reopen_multiple(queue, &local_err); - if (local_err != NULL) { - error_propagate(errp, local_err); - } - return ret; -} - - -/* - * Prepares a BlockDriverState for reopen. All changes are staged in the - * 'opaque' field of the BDRVReopenState, which is used and allocated by - * the block driver layer .bdrv_reopen_prepare() - * - * bs is the BlockDriverState to reopen - * flags are the new open flags - * queue is the reopen queue - * - * Returns 0 on success, non-zero on error. On error errp will be set - * as well. - * - * On failure, bdrv_reopen_abort() will be called to clean up any data. - * It is the responsibility of the caller to then call the abort() or - * commit() for any other BDS that have been left in a prepare() state - * - */ -int bdrv_reopen_prepare(BDRVReopenState *reopen_state, BlockReopenQueue *queue, - Error **errp) -{ - int ret = -1; - Error *local_err = NULL; - BlockDriver *drv; - - assert(reopen_state != NULL); - assert(reopen_state->bs->drv != NULL); - drv = reopen_state->bs->drv; - - /* if we are to stay read-only, do not allow permission change - * to r/w */ - if (!(reopen_state->bs->open_flags & BDRV_O_ALLOW_RDWR) && - reopen_state->flags & BDRV_O_RDWR) { - error_set(errp, QERR_DEVICE_IS_READ_ONLY, - reopen_state->bs->device_name); - goto error; - } - - - ret = bdrv_flush(reopen_state->bs); - if (ret) { - error_set(errp, ERROR_CLASS_GENERIC_ERROR, "Error (%s) flushing drive", - strerror(-ret)); - goto error; - } - - if (drv->bdrv_reopen_prepare) { - ret = drv->bdrv_reopen_prepare(reopen_state, queue, &local_err); - if (ret) { - if (local_err != NULL) { - error_propagate(errp, local_err); - } else { - error_setg(errp, "failed while preparing to reopen image '%s'", - reopen_state->bs->filename); - } - goto error; - } - } else { - /* It is currently mandatory to have a bdrv_reopen_prepare() - * handler for each supported drv. */ - error_set(errp, QERR_BLOCK_FORMAT_FEATURE_NOT_SUPPORTED, - drv->format_name, reopen_state->bs->device_name, - "reopening of file"); - ret = -1; - goto error; - } - - ret = 0; - -error: - return ret; -} - -/* - * Takes the staged changes for the reopen from bdrv_reopen_prepare(), and - * makes them final by swapping the staging BlockDriverState contents into - * the active BlockDriverState contents. - */ -void bdrv_reopen_commit(BDRVReopenState *reopen_state) -{ - BlockDriver *drv; - - assert(reopen_state != NULL); - drv = reopen_state->bs->drv; - assert(drv != NULL); - - /* If there are any driver level actions to take */ - if (drv->bdrv_reopen_commit) { - drv->bdrv_reopen_commit(reopen_state); - } - - /* set BDS specific flags now */ - reopen_state->bs->open_flags = reopen_state->flags; - reopen_state->bs->enable_write_cache = !!(reopen_state->flags & - BDRV_O_CACHE_WB); - reopen_state->bs->read_only = !(reopen_state->flags & BDRV_O_RDWR); -} - -/* - * Abort the reopen, and delete and free the staged changes in - * reopen_state - */ -void bdrv_reopen_abort(BDRVReopenState *reopen_state) -{ - BlockDriver *drv; - - assert(reopen_state != NULL); - drv = reopen_state->bs->drv; - assert(drv != NULL); - - if (drv->bdrv_reopen_abort) { - drv->bdrv_reopen_abort(reopen_state); - } -} - - -void bdrv_close(BlockDriverState *bs) -{ - if (bs->job) { - block_job_cancel_sync(bs->job); - } - bdrv_drain_all(); /* complete I/O */ - bdrv_flush(bs); - bdrv_drain_all(); /* in case flush left pending I/O */ - notifier_list_notify(&bs->close_notifiers, bs); - - if (bs->drv) { - if (bs->backing_hd) { - bdrv_delete(bs->backing_hd); - bs->backing_hd = NULL; - } - bs->drv->bdrv_close(bs); - g_free(bs->opaque); -#ifdef _WIN32 - if (bs->is_temporary) { - unlink(bs->filename); - } -#endif - bs->opaque = NULL; - bs->drv = NULL; - bs->copy_on_read = 0; - bs->backing_file[0] = '\0'; - bs->backing_format[0] = '\0'; - bs->total_sectors = 0; - bs->encrypted = 0; - bs->valid_key = 0; - bs->sg = 0; - bs->growable = 0; - QDECREF(bs->options); - bs->options = NULL; - - if (bs->file != NULL) { - bdrv_delete(bs->file); - bs->file = NULL; - } - } - - bdrv_dev_change_media_cb(bs, false); - - /*throttling disk I/O limits*/ - if (bs->io_limits_enabled) { - bdrv_io_limits_disable(bs); - } -} - -void bdrv_close_all(void) -{ - BlockDriverState *bs; - - QTAILQ_FOREACH(bs, &bdrv_states, list) { - bdrv_close(bs); - } -} - -/* - * Wait for pending requests to complete across all BlockDriverStates - * - * This function does not flush data to disk, use bdrv_flush_all() for that - * after calling this function. - * - * Note that completion of an asynchronous I/O operation can trigger any - * number of other I/O operations on other devices---for example a coroutine - * can be arbitrarily complex and a constant flow of I/O can come until the - * coroutine is complete. Because of this, it is not possible to have a - * function to drain a single device's I/O queue. - */ -void bdrv_drain_all(void) -{ - BlockDriverState *bs; - bool busy; - - do { - busy = qemu_aio_wait(); - - /* FIXME: We do not have timer support here, so this is effectively - * a busy wait. - */ - QTAILQ_FOREACH(bs, &bdrv_states, list) { - if (!qemu_co_queue_empty(&bs->throttled_reqs)) { - qemu_co_queue_restart_all(&bs->throttled_reqs); - busy = true; - } - } - } while (busy); - - /* If requests are still pending there is a bug somewhere */ - QTAILQ_FOREACH(bs, &bdrv_states, list) { - assert(QLIST_EMPTY(&bs->tracked_requests)); - assert(qemu_co_queue_empty(&bs->throttled_reqs)); - } -} - -/* make a BlockDriverState anonymous by removing from bdrv_state list. - Also, NULL terminate the device_name to prevent double remove */ -void bdrv_make_anon(BlockDriverState *bs) -{ - if (bs->device_name[0] != '\0') { - QTAILQ_REMOVE(&bdrv_states, bs, list); - } - bs->device_name[0] = '\0'; -} - -static void bdrv_rebind(BlockDriverState *bs) -{ - if (bs->drv && bs->drv->bdrv_rebind) { - bs->drv->bdrv_rebind(bs); - } -} - -static void bdrv_move_feature_fields(BlockDriverState *bs_dest, - BlockDriverState *bs_src) -{ - /* move some fields that need to stay attached to the device */ - bs_dest->open_flags = bs_src->open_flags; - - /* dev info */ - bs_dest->dev_ops = bs_src->dev_ops; - bs_dest->dev_opaque = bs_src->dev_opaque; - bs_dest->dev = bs_src->dev; - bs_dest->buffer_alignment = bs_src->buffer_alignment; - bs_dest->copy_on_read = bs_src->copy_on_read; - - bs_dest->enable_write_cache = bs_src->enable_write_cache; - - /* i/o timing parameters */ - bs_dest->slice_start = bs_src->slice_start; - bs_dest->slice_end = bs_src->slice_end; - bs_dest->slice_submitted = bs_src->slice_submitted; - bs_dest->io_limits = bs_src->io_limits; - bs_dest->throttled_reqs = bs_src->throttled_reqs; - bs_dest->block_timer = bs_src->block_timer; - bs_dest->io_limits_enabled = bs_src->io_limits_enabled; - - /* r/w error */ - bs_dest->on_read_error = bs_src->on_read_error; - bs_dest->on_write_error = bs_src->on_write_error; - - /* i/o status */ - bs_dest->iostatus_enabled = bs_src->iostatus_enabled; - bs_dest->iostatus = bs_src->iostatus; - - /* dirty bitmap */ - bs_dest->dirty_bitmap = bs_src->dirty_bitmap; - - /* job */ - bs_dest->in_use = bs_src->in_use; - bs_dest->job = bs_src->job; - - /* keep the same entry in bdrv_states */ - pstrcpy(bs_dest->device_name, sizeof(bs_dest->device_name), - bs_src->device_name); - bs_dest->list = bs_src->list; -} - -/* - * Swap bs contents for two image chains while they are live, - * while keeping required fields on the BlockDriverState that is - * actually attached to a device. - * - * This will modify the BlockDriverState fields, and swap contents - * between bs_new and bs_old. Both bs_new and bs_old are modified. - * - * bs_new is required to be anonymous. - * - * This function does not create any image files. - */ -void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old) -{ - BlockDriverState tmp; - - /* bs_new must be anonymous and shouldn't have anything fancy enabled */ - assert(bs_new->device_name[0] == '\0'); - assert(bs_new->dirty_bitmap == NULL); - assert(bs_new->job == NULL); - assert(bs_new->dev == NULL); - assert(bs_new->in_use == 0); - assert(bs_new->io_limits_enabled == false); - assert(bs_new->block_timer == NULL); - - tmp = *bs_new; - *bs_new = *bs_old; - *bs_old = tmp; - - /* there are some fields that should not be swapped, move them back */ - bdrv_move_feature_fields(&tmp, bs_old); - bdrv_move_feature_fields(bs_old, bs_new); - bdrv_move_feature_fields(bs_new, &tmp); - - /* bs_new shouldn't be in bdrv_states even after the swap! */ - assert(bs_new->device_name[0] == '\0'); - - /* Check a few fields that should remain attached to the device */ - assert(bs_new->dev == NULL); - assert(bs_new->job == NULL); - assert(bs_new->in_use == 0); - assert(bs_new->io_limits_enabled == false); - assert(bs_new->block_timer == NULL); - - bdrv_rebind(bs_new); - bdrv_rebind(bs_old); -} - -/* - * Add new bs contents at the top of an image chain while the chain is - * live, while keeping required fields on the top layer. - * - * This will modify the BlockDriverState fields, and swap contents - * between bs_new and bs_top. Both bs_new and bs_top are modified. - * - * bs_new is required to be anonymous. - * - * This function does not create any image files. - */ -void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top) -{ - bdrv_swap(bs_new, bs_top); - - /* The contents of 'tmp' will become bs_top, as we are - * swapping bs_new and bs_top contents. */ - bs_top->backing_hd = bs_new; - bs_top->open_flags &= ~BDRV_O_NO_BACKING; - pstrcpy(bs_top->backing_file, sizeof(bs_top->backing_file), - bs_new->filename); - pstrcpy(bs_top->backing_format, sizeof(bs_top->backing_format), - bs_new->drv ? bs_new->drv->format_name : ""); -} - -void bdrv_delete(BlockDriverState *bs) -{ - assert(!bs->dev); - assert(!bs->job); - assert(!bs->in_use); - - /* remove from list, if necessary */ - bdrv_make_anon(bs); - - bdrv_close(bs); - - g_free(bs); -} - -int bdrv_attach_dev(BlockDriverState *bs, void *dev) -/* TODO change to DeviceState *dev when all users are qdevified */ -{ - if (bs->dev) { - return -EBUSY; - } - bs->dev = dev; - bdrv_iostatus_reset(bs); - return 0; -} - -/* TODO qdevified devices don't use this, remove when devices are qdevified */ -void bdrv_attach_dev_nofail(BlockDriverState *bs, void *dev) -{ - if (bdrv_attach_dev(bs, dev) < 0) { - abort(); - } -} - -void bdrv_detach_dev(BlockDriverState *bs, void *dev) -/* TODO change to DeviceState *dev when all users are qdevified */ -{ - assert(bs->dev == dev); - bs->dev = NULL; - bs->dev_ops = NULL; - bs->dev_opaque = NULL; - bs->buffer_alignment = 512; -} - -/* TODO change to return DeviceState * when all users are qdevified */ -void *bdrv_get_attached_dev(BlockDriverState *bs) -{ - return bs->dev; -} - -void bdrv_set_dev_ops(BlockDriverState *bs, const BlockDevOps *ops, - void *opaque) -{ - bs->dev_ops = ops; - bs->dev_opaque = opaque; -} - -void bdrv_emit_qmp_error_event(const BlockDriverState *bdrv, - enum MonitorEvent ev, - BlockErrorAction action, bool is_read) -{ - QObject *data; - const char *action_str; - - switch (action) { - case BDRV_ACTION_REPORT: - action_str = "report"; - break; - case BDRV_ACTION_IGNORE: - action_str = "ignore"; - break; - case BDRV_ACTION_STOP: - action_str = "stop"; - break; - default: - abort(); - } - - data = qobject_from_jsonf("{ 'device': %s, 'action': %s, 'operation': %s }", - bdrv->device_name, - action_str, - is_read ? "read" : "write"); - monitor_protocol_event(ev, data); - - qobject_decref(data); -} - -static void bdrv_emit_qmp_eject_event(BlockDriverState *bs, bool ejected) -{ - QObject *data; - - data = qobject_from_jsonf("{ 'device': %s, 'tray-open': %i }", - bdrv_get_device_name(bs), ejected); - monitor_protocol_event(QEVENT_DEVICE_TRAY_MOVED, data); - - qobject_decref(data); -} - -static void bdrv_dev_change_media_cb(BlockDriverState *bs, bool load) -{ - if (bs->dev_ops && bs->dev_ops->change_media_cb) { - bool tray_was_closed = !bdrv_dev_is_tray_open(bs); - bs->dev_ops->change_media_cb(bs->dev_opaque, load); - if (tray_was_closed) { - /* tray open */ - bdrv_emit_qmp_eject_event(bs, true); - } - if (load) { - /* tray close */ - bdrv_emit_qmp_eject_event(bs, false); - } - } -} - -bool bdrv_dev_has_removable_media(BlockDriverState *bs) -{ - return !bs->dev || (bs->dev_ops && bs->dev_ops->change_media_cb); -} - -void bdrv_dev_eject_request(BlockDriverState *bs, bool force) -{ - if (bs->dev_ops && bs->dev_ops->eject_request_cb) { - bs->dev_ops->eject_request_cb(bs->dev_opaque, force); - } -} - -bool bdrv_dev_is_tray_open(BlockDriverState *bs) -{ - if (bs->dev_ops && bs->dev_ops->is_tray_open) { - return bs->dev_ops->is_tray_open(bs->dev_opaque); - } - return false; -} - -static void bdrv_dev_resize_cb(BlockDriverState *bs) -{ - if (bs->dev_ops && bs->dev_ops->resize_cb) { - bs->dev_ops->resize_cb(bs->dev_opaque); - } -} - -bool bdrv_dev_is_medium_locked(BlockDriverState *bs) -{ - if (bs->dev_ops && bs->dev_ops->is_medium_locked) { - return bs->dev_ops->is_medium_locked(bs->dev_opaque); - } - return false; -} - -/* - * Run consistency checks on an image - * - * Returns 0 if the check could be completed (it doesn't mean that the image is - * free of errors) or -errno when an internal error occurred. The results of the - * check are stored in res. - */ -int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix) -{ - if (bs->drv->bdrv_check == NULL) { - return -ENOTSUP; - } - - memset(res, 0, sizeof(*res)); - return bs->drv->bdrv_check(bs, res, fix); -} - -#define COMMIT_BUF_SECTORS 2048 - -/* commit COW file into the raw image */ -int bdrv_commit(BlockDriverState *bs) -{ - BlockDriver *drv = bs->drv; - int64_t sector, total_sectors; - int n, ro, open_flags; - int ret = 0; - uint8_t *buf; - char filename[PATH_MAX]; - - if (!drv) - return -ENOMEDIUM; - - if (!bs->backing_hd) { - return -ENOTSUP; - } - - if (bdrv_in_use(bs) || bdrv_in_use(bs->backing_hd)) { - return -EBUSY; - } - - ro = bs->backing_hd->read_only; - /* Use pstrcpy (not strncpy): filename must be NUL-terminated. */ - pstrcpy(filename, sizeof(filename), bs->backing_hd->filename); - open_flags = bs->backing_hd->open_flags; - - if (ro) { - if (bdrv_reopen(bs->backing_hd, open_flags | BDRV_O_RDWR, NULL)) { - return -EACCES; - } - } - - total_sectors = bdrv_getlength(bs) >> BDRV_SECTOR_BITS; - buf = g_malloc(COMMIT_BUF_SECTORS * BDRV_SECTOR_SIZE); - - for (sector = 0; sector < total_sectors; sector += n) { - if (bdrv_is_allocated(bs, sector, COMMIT_BUF_SECTORS, &n)) { - - if (bdrv_read(bs, sector, buf, n) != 0) { - ret = -EIO; - goto ro_cleanup; - } - - if (bdrv_write(bs->backing_hd, sector, buf, n) != 0) { - ret = -EIO; - goto ro_cleanup; - } - } - } - - if (drv->bdrv_make_empty) { - ret = drv->bdrv_make_empty(bs); - bdrv_flush(bs); - } - - /* - * Make sure all data we wrote to the backing device is actually - * stable on disk. - */ - if (bs->backing_hd) - bdrv_flush(bs->backing_hd); - -ro_cleanup: - g_free(buf); - - if (ro) { - /* ignoring error return here */ - bdrv_reopen(bs->backing_hd, open_flags & ~BDRV_O_RDWR, NULL); - } - - return ret; -} - -int bdrv_commit_all(void) -{ - BlockDriverState *bs; - - QTAILQ_FOREACH(bs, &bdrv_states, list) { - if (bs->drv && bs->backing_hd) { - int ret = bdrv_commit(bs); - if (ret < 0) { - return ret; - } - } - } - return 0; -} - -/** - * Remove an active request from the tracked requests list - * - * This function should be called when a tracked request is completing. - */ -static void tracked_request_end(BdrvTrackedRequest *req) -{ - QLIST_REMOVE(req, list); - qemu_co_queue_restart_all(&req->wait_queue); -} - -/** - * Add an active request to the tracked requests list - */ -static void tracked_request_begin(BdrvTrackedRequest *req, - BlockDriverState *bs, - int64_t sector_num, - int nb_sectors, bool is_write) -{ - *req = (BdrvTrackedRequest){ - .bs = bs, - .sector_num = sector_num, - .nb_sectors = nb_sectors, - .is_write = is_write, - .co = qemu_coroutine_self(), - }; - - qemu_co_queue_init(&req->wait_queue); - - QLIST_INSERT_HEAD(&bs->tracked_requests, req, list); -} - -/** - * Round a region to cluster boundaries - */ -void bdrv_round_to_clusters(BlockDriverState *bs, - int64_t sector_num, int nb_sectors, - int64_t *cluster_sector_num, - int *cluster_nb_sectors) -{ - BlockDriverInfo bdi; - - if (bdrv_get_info(bs, &bdi) < 0 || bdi.cluster_size == 0) { - *cluster_sector_num = sector_num; - *cluster_nb_sectors = nb_sectors; - } else { - int64_t c = bdi.cluster_size / BDRV_SECTOR_SIZE; - *cluster_sector_num = QEMU_ALIGN_DOWN(sector_num, c); - *cluster_nb_sectors = QEMU_ALIGN_UP(sector_num - *cluster_sector_num + - nb_sectors, c); - } -} - -static bool tracked_request_overlaps(BdrvTrackedRequest *req, - int64_t sector_num, int nb_sectors) { - /* aaaa bbbb */ - if (sector_num >= req->sector_num + req->nb_sectors) { - return false; - } - /* bbbb aaaa */ - if (req->sector_num >= sector_num + nb_sectors) { - return false; - } - return true; -} - -static void coroutine_fn wait_for_overlapping_requests(BlockDriverState *bs, - int64_t sector_num, int nb_sectors) -{ - BdrvTrackedRequest *req; - int64_t cluster_sector_num; - int cluster_nb_sectors; - bool retry; - - /* If we touch the same cluster it counts as an overlap. This guarantees - * that allocating writes will be serialized and not race with each other - * for the same cluster. For example, in copy-on-read it ensures that the - * CoR read and write operations are atomic and guest writes cannot - * interleave between them. - */ - bdrv_round_to_clusters(bs, sector_num, nb_sectors, - &cluster_sector_num, &cluster_nb_sectors); - - do { - retry = false; - QLIST_FOREACH(req, &bs->tracked_requests, list) { - if (tracked_request_overlaps(req, cluster_sector_num, - cluster_nb_sectors)) { - /* Hitting this means there was a reentrant request, for - * example, a block driver issuing nested requests. This must - * never happen since it means deadlock. - */ - assert(qemu_coroutine_self() != req->co); - - qemu_co_queue_wait(&req->wait_queue); - retry = true; - break; - } - } - } while (retry); -} - -/* - * Return values: - * 0 - success - * -EINVAL - backing format specified, but no file - * -ENOSPC - can't update the backing file because no space is left in the - * image file header - * -ENOTSUP - format driver doesn't support changing the backing file - */ -int bdrv_change_backing_file(BlockDriverState *bs, - const char *backing_file, const char *backing_fmt) -{ - BlockDriver *drv = bs->drv; - int ret; - - /* Backing file format doesn't make sense without a backing file */ - if (backing_fmt && !backing_file) { - return -EINVAL; - } - - if (drv->bdrv_change_backing_file != NULL) { - ret = drv->bdrv_change_backing_file(bs, backing_file, backing_fmt); - } else { - ret = -ENOTSUP; - } - - if (ret == 0) { - pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_file ?: ""); - pstrcpy(bs->backing_format, sizeof(bs->backing_format), backing_fmt ?: ""); - } - return ret; -} - -/* - * Finds the image layer in the chain that has 'bs' as its backing file. - * - * active is the current topmost image. - * - * Returns NULL if bs is not found in active's image chain, - * or if active == bs. - */ -BlockDriverState *bdrv_find_overlay(BlockDriverState *active, - BlockDriverState *bs) -{ - BlockDriverState *overlay = NULL; - BlockDriverState *intermediate; - - assert(active != NULL); - assert(bs != NULL); - - /* if bs is the same as active, then by definition it has no overlay - */ - if (active == bs) { - return NULL; - } - - intermediate = active; - while (intermediate->backing_hd) { - if (intermediate->backing_hd == bs) { - overlay = intermediate; - break; - } - intermediate = intermediate->backing_hd; - } - - return overlay; -} - -typedef struct BlkIntermediateStates { - BlockDriverState *bs; - QSIMPLEQ_ENTRY(BlkIntermediateStates) entry; -} BlkIntermediateStates; - - -/* - * Drops images above 'base' up to and including 'top', and sets the image - * above 'top' to have base as its backing file. - * - * Requires that the overlay to 'top' is opened r/w, so that the backing file - * information in 'bs' can be properly updated. - * - * E.g., this will convert the following chain: - * bottom <- base <- intermediate <- top <- active - * - * to - * - * bottom <- base <- active - * - * It is allowed for bottom==base, in which case it converts: - * - * base <- intermediate <- top <- active - * - * to - * - * base <- active - * - * Error conditions: - * if active == top, that is considered an error - * - */ -int bdrv_drop_intermediate(BlockDriverState *active, BlockDriverState *top, - BlockDriverState *base) -{ - BlockDriverState *intermediate; - BlockDriverState *base_bs = NULL; - BlockDriverState *new_top_bs = NULL; - BlkIntermediateStates *intermediate_state, *next; - int ret = -EIO; - - QSIMPLEQ_HEAD(states_to_delete, BlkIntermediateStates) states_to_delete; - QSIMPLEQ_INIT(&states_to_delete); - - if (!top->drv || !base->drv) { - goto exit; - } - - new_top_bs = bdrv_find_overlay(active, top); - - if (new_top_bs == NULL) { - /* we could not find the image above 'top', this is an error */ - goto exit; - } - - /* special case of new_top_bs->backing_hd already pointing to base - nothing - * to do, no intermediate images */ - if (new_top_bs->backing_hd == base) { - ret = 0; - goto exit; - } - - intermediate = top; - - /* now we will go down through the list, and add each BDS we find - * into our deletion queue, until we hit the 'base' - */ - while (intermediate) { - intermediate_state = g_malloc0(sizeof(BlkIntermediateStates)); - intermediate_state->bs = intermediate; - QSIMPLEQ_INSERT_TAIL(&states_to_delete, intermediate_state, entry); - - if (intermediate->backing_hd == base) { - base_bs = intermediate->backing_hd; - break; - } - intermediate = intermediate->backing_hd; - } - if (base_bs == NULL) { - /* something went wrong, we did not end at the base. safely - * unravel everything, and exit with error */ - goto exit; - } - - /* success - we can delete the intermediate states, and link top->base */ - ret = bdrv_change_backing_file(new_top_bs, base_bs->filename, - base_bs->drv ? base_bs->drv->format_name : ""); - if (ret) { - goto exit; - } - new_top_bs->backing_hd = base_bs; - - - QSIMPLEQ_FOREACH_SAFE(intermediate_state, &states_to_delete, entry, next) { - /* so that bdrv_close() does not recursively close the chain */ - intermediate_state->bs->backing_hd = NULL; - bdrv_delete(intermediate_state->bs); - } - ret = 0; - -exit: - QSIMPLEQ_FOREACH_SAFE(intermediate_state, &states_to_delete, entry, next) { - g_free(intermediate_state); - } - return ret; -} - - -static int bdrv_check_byte_request(BlockDriverState *bs, int64_t offset, - size_t size) -{ - int64_t len; - - if (!bdrv_is_inserted(bs)) - return -ENOMEDIUM; - - if (bs->growable) - return 0; - - len = bdrv_getlength(bs); - - if (offset < 0) - return -EIO; - - if ((offset > len) || (len - offset < size)) - return -EIO; - - return 0; -} - -static int bdrv_check_request(BlockDriverState *bs, int64_t sector_num, - int nb_sectors) -{ - return bdrv_check_byte_request(bs, sector_num * BDRV_SECTOR_SIZE, - nb_sectors * BDRV_SECTOR_SIZE); -} - -typedef struct RwCo { - BlockDriverState *bs; - int64_t sector_num; - int nb_sectors; - QEMUIOVector *qiov; - bool is_write; - int ret; -} RwCo; - -static void coroutine_fn bdrv_rw_co_entry(void *opaque) -{ - RwCo *rwco = opaque; - - if (!rwco->is_write) { - rwco->ret = bdrv_co_do_readv(rwco->bs, rwco->sector_num, - rwco->nb_sectors, rwco->qiov, 0); - } else { - rwco->ret = bdrv_co_do_writev(rwco->bs, rwco->sector_num, - rwco->nb_sectors, rwco->qiov, 0); - } -} - -/* - * Process a vectored synchronous request using coroutines - */ -static int bdrv_rwv_co(BlockDriverState *bs, int64_t sector_num, - QEMUIOVector *qiov, bool is_write) -{ - Coroutine *co; - RwCo rwco = { - .bs = bs, - .sector_num = sector_num, - .nb_sectors = qiov->size >> BDRV_SECTOR_BITS, - .qiov = qiov, - .is_write = is_write, - .ret = NOT_DONE, - }; - assert((qiov->size & (BDRV_SECTOR_SIZE - 1)) == 0); - - /** - * In sync call context, when the vcpu is blocked, this throttling timer - * will not fire; so the I/O throttling function has to be disabled here - * if it has been enabled. - */ - if (bs->io_limits_enabled) { - fprintf(stderr, "Disabling I/O throttling on '%s' due " - "to synchronous I/O.\n", bdrv_get_device_name(bs)); - bdrv_io_limits_disable(bs); - } - - if (qemu_in_coroutine()) { - /* Fast-path if already in coroutine context */ - bdrv_rw_co_entry(&rwco); - } else { - co = qemu_coroutine_create(bdrv_rw_co_entry); - qemu_coroutine_enter(co, &rwco); - while (rwco.ret == NOT_DONE) { - qemu_aio_wait(); - } - } - return rwco.ret; -} - -/* - * Process a synchronous request using coroutines - */ -static int bdrv_rw_co(BlockDriverState *bs, int64_t sector_num, uint8_t *buf, - int nb_sectors, bool is_write) -{ - QEMUIOVector qiov; - struct iovec iov = { - .iov_base = (void *)buf, - .iov_len = nb_sectors * BDRV_SECTOR_SIZE, - }; - - qemu_iovec_init_external(&qiov, &iov, 1); - return bdrv_rwv_co(bs, sector_num, &qiov, is_write); -} - -/* return < 0 if error. See bdrv_write() for the return codes */ -int bdrv_read(BlockDriverState *bs, int64_t sector_num, - uint8_t *buf, int nb_sectors) -{ - return bdrv_rw_co(bs, sector_num, buf, nb_sectors, false); -} - -/* Just like bdrv_read(), but with I/O throttling temporarily disabled */ -int bdrv_read_unthrottled(BlockDriverState *bs, int64_t sector_num, - uint8_t *buf, int nb_sectors) -{ - bool enabled; - int ret; - - enabled = bs->io_limits_enabled; - bs->io_limits_enabled = false; - ret = bdrv_read(bs, 0, buf, 1); - bs->io_limits_enabled = enabled; - return ret; -} - -/* Return < 0 if error. Important errors are: - -EIO generic I/O error (may happen for all errors) - -ENOMEDIUM No media inserted. - -EINVAL Invalid sector number or nb_sectors - -EACCES Trying to write a read-only device -*/ -int bdrv_write(BlockDriverState *bs, int64_t sector_num, - const uint8_t *buf, int nb_sectors) -{ - return bdrv_rw_co(bs, sector_num, (uint8_t *)buf, nb_sectors, true); -} - -int bdrv_writev(BlockDriverState *bs, int64_t sector_num, QEMUIOVector *qiov) -{ - return bdrv_rwv_co(bs, sector_num, qiov, true); -} - -int bdrv_pread(BlockDriverState *bs, int64_t offset, - void *buf, int count1) -{ - uint8_t tmp_buf[BDRV_SECTOR_SIZE]; - int len, nb_sectors, count; - int64_t sector_num; - int ret; - - count = count1; - /* first read to align to sector start */ - len = (BDRV_SECTOR_SIZE - offset) & (BDRV_SECTOR_SIZE - 1); - if (len > count) - len = count; - sector_num = offset >> BDRV_SECTOR_BITS; - if (len > 0) { - if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0) - return ret; - memcpy(buf, tmp_buf + (offset & (BDRV_SECTOR_SIZE - 1)), len); - count -= len; - if (count == 0) - return count1; - sector_num++; - buf += len; - } - - /* read the sectors "in place" */ - nb_sectors = count >> BDRV_SECTOR_BITS; - if (nb_sectors > 0) { - if ((ret = bdrv_read(bs, sector_num, buf, nb_sectors)) < 0) - return ret; - sector_num += nb_sectors; - len = nb_sectors << BDRV_SECTOR_BITS; - buf += len; - count -= len; - } - - /* add data from the last sector */ - if (count > 0) { - if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0) - return ret; - memcpy(buf, tmp_buf, count); - } - return count1; -} - -int bdrv_pwritev(BlockDriverState *bs, int64_t offset, QEMUIOVector *qiov) -{ - uint8_t tmp_buf[BDRV_SECTOR_SIZE]; - int len, nb_sectors, count; - int64_t sector_num; - int ret; - - count = qiov->size; - - /* first write to align to sector start */ - len = (BDRV_SECTOR_SIZE - offset) & (BDRV_SECTOR_SIZE - 1); - if (len > count) - len = count; - sector_num = offset >> BDRV_SECTOR_BITS; - if (len > 0) { - if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0) - return ret; - qemu_iovec_to_buf(qiov, 0, tmp_buf + (offset & (BDRV_SECTOR_SIZE - 1)), - len); - if ((ret = bdrv_write(bs, sector_num, tmp_buf, 1)) < 0) - return ret; - count -= len; - if (count == 0) - return qiov->size; - sector_num++; - } - - /* write the sectors "in place" */ - nb_sectors = count >> BDRV_SECTOR_BITS; - if (nb_sectors > 0) { - QEMUIOVector qiov_inplace; - - qemu_iovec_init(&qiov_inplace, qiov->niov); - qemu_iovec_concat(&qiov_inplace, qiov, len, - nb_sectors << BDRV_SECTOR_BITS); - ret = bdrv_writev(bs, sector_num, &qiov_inplace); - qemu_iovec_destroy(&qiov_inplace); - if (ret < 0) { - return ret; - } - - sector_num += nb_sectors; - len = nb_sectors << BDRV_SECTOR_BITS; - count -= len; - } - - /* add data from the last sector */ - if (count > 0) { - if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0) - return ret; - qemu_iovec_to_buf(qiov, qiov->size - count, tmp_buf, count); - if ((ret = bdrv_write(bs, sector_num, tmp_buf, 1)) < 0) - return ret; - } - return qiov->size; -} - -int bdrv_pwrite(BlockDriverState *bs, int64_t offset, - const void *buf, int count1) -{ - QEMUIOVector qiov; - struct iovec iov = { - .iov_base = (void *) buf, - .iov_len = count1, - }; - - qemu_iovec_init_external(&qiov, &iov, 1); - return bdrv_pwritev(bs, offset, &qiov); -} - -/* - * Writes to the file and ensures that no writes are reordered across this - * request (acts as a barrier) - * - * Returns 0 on success, -errno in error cases. - */ -int bdrv_pwrite_sync(BlockDriverState *bs, int64_t offset, - const void *buf, int count) -{ - int ret; - - ret = bdrv_pwrite(bs, offset, buf, count); - if (ret < 0) { - return ret; - } - - /* No flush needed for cache modes that already do it */ - if (bs->enable_write_cache) { - bdrv_flush(bs); - } - - return 0; -} - -static int coroutine_fn bdrv_co_do_copy_on_readv(BlockDriverState *bs, - int64_t sector_num, int nb_sectors, QEMUIOVector *qiov) -{ - /* Perform I/O through a temporary buffer so that users who scribble over - * their read buffer while the operation is in progress do not end up - * modifying the image file. This is critical for zero-copy guest I/O - * where anything might happen inside guest memory. - */ - void *bounce_buffer; - - BlockDriver *drv = bs->drv; - struct iovec iov; - QEMUIOVector bounce_qiov; - int64_t cluster_sector_num; - int cluster_nb_sectors; - size_t skip_bytes; - int ret; - - /* Cover entire cluster so no additional backing file I/O is required when - * allocating cluster in the image file. - */ - bdrv_round_to_clusters(bs, sector_num, nb_sectors, - &cluster_sector_num, &cluster_nb_sectors); - - trace_bdrv_co_do_copy_on_readv(bs, sector_num, nb_sectors, - cluster_sector_num, cluster_nb_sectors); - - iov.iov_len = cluster_nb_sectors * BDRV_SECTOR_SIZE; - iov.iov_base = bounce_buffer = qemu_blockalign(bs, iov.iov_len); - qemu_iovec_init_external(&bounce_qiov, &iov, 1); - - ret = drv->bdrv_co_readv(bs, cluster_sector_num, cluster_nb_sectors, - &bounce_qiov); - if (ret < 0) { - goto err; - } - - if (drv->bdrv_co_write_zeroes && - buffer_is_zero(bounce_buffer, iov.iov_len)) { - ret = bdrv_co_do_write_zeroes(bs, cluster_sector_num, - cluster_nb_sectors); - } else { - /* This does not change the data on the disk, it is not necessary - * to flush even in cache=writethrough mode. - */ - ret = drv->bdrv_co_writev(bs, cluster_sector_num, cluster_nb_sectors, - &bounce_qiov); - } - - if (ret < 0) { - /* It might be okay to ignore write errors for guest requests. If this - * is a deliberate copy-on-read then we don't want to ignore the error. - * Simply report it in all cases. - */ - goto err; - } - - skip_bytes = (sector_num - cluster_sector_num) * BDRV_SECTOR_SIZE; - qemu_iovec_from_buf(qiov, 0, bounce_buffer + skip_bytes, - nb_sectors * BDRV_SECTOR_SIZE); - -err: - qemu_vfree(bounce_buffer); - return ret; -} - -/* - * Handle a read request in coroutine context - */ -static int coroutine_fn bdrv_co_do_readv(BlockDriverState *bs, - int64_t sector_num, int nb_sectors, QEMUIOVector *qiov, - BdrvRequestFlags flags) -{ - BlockDriver *drv = bs->drv; - BdrvTrackedRequest req; - int ret; - - if (!drv) { - return -ENOMEDIUM; - } - if (bdrv_check_request(bs, sector_num, nb_sectors)) { - return -EIO; - } - - /* throttling disk read I/O */ - if (bs->io_limits_enabled) { - bdrv_io_limits_intercept(bs, false, nb_sectors); - } - - if (bs->copy_on_read) { - flags |= BDRV_REQ_COPY_ON_READ; - } - if (flags & BDRV_REQ_COPY_ON_READ) { - bs->copy_on_read_in_flight++; - } - - if (bs->copy_on_read_in_flight) { - wait_for_overlapping_requests(bs, sector_num, nb_sectors); - } - - tracked_request_begin(&req, bs, sector_num, nb_sectors, false); - - if (flags & BDRV_REQ_COPY_ON_READ) { - int pnum; - - ret = bdrv_co_is_allocated(bs, sector_num, nb_sectors, &pnum); - if (ret < 0) { - goto out; - } - - if (!ret || pnum != nb_sectors) { - ret = bdrv_co_do_copy_on_readv(bs, sector_num, nb_sectors, qiov); - goto out; - } - } - - ret = drv->bdrv_co_readv(bs, sector_num, nb_sectors, qiov); - -out: - tracked_request_end(&req); - - if (flags & BDRV_REQ_COPY_ON_READ) { - bs->copy_on_read_in_flight--; - } - - return ret; -} - -int coroutine_fn bdrv_co_readv(BlockDriverState *bs, int64_t sector_num, - int nb_sectors, QEMUIOVector *qiov) -{ - trace_bdrv_co_readv(bs, sector_num, nb_sectors); - - return bdrv_co_do_readv(bs, sector_num, nb_sectors, qiov, 0); -} - -int coroutine_fn bdrv_co_copy_on_readv(BlockDriverState *bs, - int64_t sector_num, int nb_sectors, QEMUIOVector *qiov) -{ - trace_bdrv_co_copy_on_readv(bs, sector_num, nb_sectors); - - return bdrv_co_do_readv(bs, sector_num, nb_sectors, qiov, - BDRV_REQ_COPY_ON_READ); -} - -static int coroutine_fn bdrv_co_do_write_zeroes(BlockDriverState *bs, - int64_t sector_num, int nb_sectors) -{ - BlockDriver *drv = bs->drv; - QEMUIOVector qiov; - struct iovec iov; - int ret; - - /* TODO Emulate only part of misaligned requests instead of letting block - * drivers return -ENOTSUP and emulate everything */ - - /* First try the efficient write zeroes operation */ - if (drv->bdrv_co_write_zeroes) { - ret = drv->bdrv_co_write_zeroes(bs, sector_num, nb_sectors); - if (ret != -ENOTSUP) { - return ret; - } - } - - /* Fall back to bounce buffer if write zeroes is unsupported */ - iov.iov_len = nb_sectors * BDRV_SECTOR_SIZE; - iov.iov_base = qemu_blockalign(bs, iov.iov_len); - memset(iov.iov_base, 0, iov.iov_len); - qemu_iovec_init_external(&qiov, &iov, 1); - - ret = drv->bdrv_co_writev(bs, sector_num, nb_sectors, &qiov); - - qemu_vfree(iov.iov_base); - return ret; -} - -/* - * Handle a write request in coroutine context - */ -static int coroutine_fn bdrv_co_do_writev(BlockDriverState *bs, - int64_t sector_num, int nb_sectors, QEMUIOVector *qiov, - BdrvRequestFlags flags) -{ - BlockDriver *drv = bs->drv; - BdrvTrackedRequest req; - int ret; - - if (!bs->drv) { - return -ENOMEDIUM; - } - if (bs->read_only) { - return -EACCES; - } - if (bdrv_check_request(bs, sector_num, nb_sectors)) { - return -EIO; - } - - /* throttling disk write I/O */ - if (bs->io_limits_enabled) { - bdrv_io_limits_intercept(bs, true, nb_sectors); - } - - if (bs->copy_on_read_in_flight) { - wait_for_overlapping_requests(bs, sector_num, nb_sectors); - } - - tracked_request_begin(&req, bs, sector_num, nb_sectors, true); - - ret = notifier_with_return_list_notify(&bs->before_write_notifiers, &req); - - if (ret < 0) { - /* Do nothing, write notifier decided to fail this request */ - } else if (flags & BDRV_REQ_ZERO_WRITE) { - ret = bdrv_co_do_write_zeroes(bs, sector_num, nb_sectors); - } else { - ret = drv->bdrv_co_writev(bs, sector_num, nb_sectors, qiov); - } - - if (ret == 0 && !bs->enable_write_cache) { - ret = bdrv_co_flush(bs); - } - - if (bs->dirty_bitmap) { - bdrv_set_dirty(bs, sector_num, nb_sectors); - } - - if (bs->wr_highest_sector < sector_num + nb_sectors - 1) { - bs->wr_highest_sector = sector_num + nb_sectors - 1; - } - - tracked_request_end(&req); - - return ret; -} - -int coroutine_fn bdrv_co_writev(BlockDriverState *bs, int64_t sector_num, - int nb_sectors, QEMUIOVector *qiov) -{ - trace_bdrv_co_writev(bs, sector_num, nb_sectors); - - return bdrv_co_do_writev(bs, sector_num, nb_sectors, qiov, 0); -} - -int coroutine_fn bdrv_co_write_zeroes(BlockDriverState *bs, - int64_t sector_num, int nb_sectors) -{ - trace_bdrv_co_write_zeroes(bs, sector_num, nb_sectors); - - return bdrv_co_do_writev(bs, sector_num, nb_sectors, NULL, - BDRV_REQ_ZERO_WRITE); -} - -/** - * Truncate file to 'offset' bytes (needed only for file protocols) - */ -int bdrv_truncate(BlockDriverState *bs, int64_t offset) -{ - BlockDriver *drv = bs->drv; - int ret; - if (!drv) - return -ENOMEDIUM; - if (!drv->bdrv_truncate) - return -ENOTSUP; - if (bs->read_only) - return -EACCES; - if (bdrv_in_use(bs)) - return -EBUSY; - ret = drv->bdrv_truncate(bs, offset); - if (ret == 0) { - ret = refresh_total_sectors(bs, offset >> BDRV_SECTOR_BITS); - bdrv_dev_resize_cb(bs); - } - return ret; -} - -/** - * Length of a allocated file in bytes. Sparse files are counted by actual - * allocated space. Return < 0 if error or unknown. - */ -int64_t bdrv_get_allocated_file_size(BlockDriverState *bs) -{ - BlockDriver *drv = bs->drv; - if (!drv) { - return -ENOMEDIUM; - } - if (drv->bdrv_get_allocated_file_size) { - return drv->bdrv_get_allocated_file_size(bs); - } - if (bs->file) { - return bdrv_get_allocated_file_size(bs->file); - } - return -ENOTSUP; -} - -/** - * Length of a file in bytes. Return < 0 if error or unknown. - */ -int64_t bdrv_getlength(BlockDriverState *bs) -{ - BlockDriver *drv = bs->drv; - if (!drv) - return -ENOMEDIUM; - - if (bs->growable || bdrv_dev_has_removable_media(bs)) { - if (drv->bdrv_getlength) { - return drv->bdrv_getlength(bs); - } - } - return bs->total_sectors * BDRV_SECTOR_SIZE; -} - -/* return 0 as number of sectors if no device present or error */ -void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr) -{ - int64_t length; - length = bdrv_getlength(bs); - if (length < 0) - length = 0; - else - length = length >> BDRV_SECTOR_BITS; - *nb_sectors_ptr = length; -} - -/* throttling disk io limits */ -void bdrv_set_io_limits(BlockDriverState *bs, - BlockIOLimit *io_limits) -{ - bs->io_limits = *io_limits; - bs->io_limits_enabled = bdrv_io_limits_enabled(bs); -} - -void bdrv_set_on_error(BlockDriverState *bs, BlockdevOnError on_read_error, - BlockdevOnError on_write_error) -{ - bs->on_read_error = on_read_error; - bs->on_write_error = on_write_error; -} - -BlockdevOnError bdrv_get_on_error(BlockDriverState *bs, bool is_read) -{ - return is_read ? bs->on_read_error : bs->on_write_error; -} - -BlockErrorAction bdrv_get_error_action(BlockDriverState *bs, bool is_read, int error) -{ - BlockdevOnError on_err = is_read ? bs->on_read_error : bs->on_write_error; - - switch (on_err) { - case BLOCKDEV_ON_ERROR_ENOSPC: - return (error == ENOSPC) ? BDRV_ACTION_STOP : BDRV_ACTION_REPORT; - case BLOCKDEV_ON_ERROR_STOP: - return BDRV_ACTION_STOP; - case BLOCKDEV_ON_ERROR_REPORT: - return BDRV_ACTION_REPORT; - case BLOCKDEV_ON_ERROR_IGNORE: - return BDRV_ACTION_IGNORE; - default: - abort(); - } -} - -/* This is done by device models because, while the block layer knows - * about the error, it does not know whether an operation comes from - * the device or the block layer (from a job, for example). - */ -void bdrv_error_action(BlockDriverState *bs, BlockErrorAction action, - bool is_read, int error) -{ - assert(error >= 0); - bdrv_emit_qmp_error_event(bs, QEVENT_BLOCK_IO_ERROR, action, is_read); - if (action == BDRV_ACTION_STOP) { - vm_stop(RUN_STATE_IO_ERROR); - bdrv_iostatus_set_err(bs, error); - } -} - -int bdrv_is_read_only(BlockDriverState *bs) -{ - return bs->read_only; -} - -int bdrv_is_sg(BlockDriverState *bs) -{ - return bs->sg; -} - -int bdrv_enable_write_cache(BlockDriverState *bs) -{ - return bs->enable_write_cache; -} - -void bdrv_set_enable_write_cache(BlockDriverState *bs, bool wce) -{ - bs->enable_write_cache = wce; - - /* so a reopen() will preserve wce */ - if (wce) { - bs->open_flags |= BDRV_O_CACHE_WB; - } else { - bs->open_flags &= ~BDRV_O_CACHE_WB; - } -} - -int bdrv_is_encrypted(BlockDriverState *bs) -{ - if (bs->backing_hd && bs->backing_hd->encrypted) - return 1; - return bs->encrypted; -} - -int bdrv_key_required(BlockDriverState *bs) -{ - BlockDriverState *backing_hd = bs->backing_hd; - - if (backing_hd && backing_hd->encrypted && !backing_hd->valid_key) - return 1; - return (bs->encrypted && !bs->valid_key); -} - -int bdrv_set_key(BlockDriverState *bs, const char *key) -{ - int ret; - if (bs->backing_hd && bs->backing_hd->encrypted) { - ret = bdrv_set_key(bs->backing_hd, key); - if (ret < 0) - return ret; - if (!bs->encrypted) - return 0; - } - if (!bs->encrypted) { - return -EINVAL; - } else if (!bs->drv || !bs->drv->bdrv_set_key) { - return -ENOMEDIUM; - } - ret = bs->drv->bdrv_set_key(bs, key); - if (ret < 0) { - bs->valid_key = 0; - } else if (!bs->valid_key) { - bs->valid_key = 1; - /* call the change callback now, we skipped it on open */ - bdrv_dev_change_media_cb(bs, true); - } - return ret; -} - -const char *bdrv_get_format_name(BlockDriverState *bs) -{ - return bs->drv ? bs->drv->format_name : NULL; -} - -void bdrv_iterate_format(void (*it)(void *opaque, const char *name), - void *opaque) -{ - BlockDriver *drv; - - QLIST_FOREACH(drv, &bdrv_drivers, list) { - it(opaque, drv->format_name); - } -} - -BlockDriverState *bdrv_find(const char *name) -{ - BlockDriverState *bs; - - QTAILQ_FOREACH(bs, &bdrv_states, list) { - if (!strcmp(name, bs->device_name)) { - return bs; - } - } - return NULL; -} - -BlockDriverState *bdrv_next(BlockDriverState *bs) -{ - if (!bs) { - return QTAILQ_FIRST(&bdrv_states); - } - return QTAILQ_NEXT(bs, list); -} - -void bdrv_iterate(void (*it)(void *opaque, BlockDriverState *bs), void *opaque) -{ - BlockDriverState *bs; - - QTAILQ_FOREACH(bs, &bdrv_states, list) { - it(opaque, bs); - } -} - -const char *bdrv_get_device_name(BlockDriverState *bs) -{ - return bs->device_name; -} - -int bdrv_get_flags(BlockDriverState *bs) -{ - return bs->open_flags; -} - -int bdrv_flush_all(void) -{ - BlockDriverState *bs; - int result = 0; - - QTAILQ_FOREACH(bs, &bdrv_states, list) { - int ret = bdrv_flush(bs); - if (ret < 0 && !result) { - result = ret; - } - } - - return result; -} - -int bdrv_has_zero_init_1(BlockDriverState *bs) -{ - return 1; -} - -int bdrv_has_zero_init(BlockDriverState *bs) -{ - assert(bs->drv); - - if (bs->drv->bdrv_has_zero_init) { - return bs->drv->bdrv_has_zero_init(bs); - } - - /* safe default */ - return 0; -} - -typedef struct BdrvCoIsAllocatedData { - BlockDriverState *bs; - BlockDriverState *base; - int64_t sector_num; - int nb_sectors; - int *pnum; - int ret; - bool done; -} BdrvCoIsAllocatedData; - -/* - * Returns true iff the specified sector is present in the disk image. Drivers - * not implementing the functionality are assumed to not support backing files, - * hence all their sectors are reported as allocated. - * - * If 'sector_num' is beyond the end of the disk image the return value is 0 - * and 'pnum' is set to 0. - * - * 'pnum' is set to the number of sectors (including and immediately following - * the specified sector) that are known to be in the same - * allocated/unallocated state. - * - * 'nb_sectors' is the max value 'pnum' should be set to. If nb_sectors goes - * beyond the end of the disk image it will be clamped. - */ -int coroutine_fn bdrv_co_is_allocated(BlockDriverState *bs, int64_t sector_num, - int nb_sectors, int *pnum) -{ - int64_t n; - - if (sector_num >= bs->total_sectors) { - *pnum = 0; - return 0; - } - - n = bs->total_sectors - sector_num; - if (n < nb_sectors) { - nb_sectors = n; - } - - if (!bs->drv->bdrv_co_is_allocated) { - *pnum = nb_sectors; - return 1; - } - - return bs->drv->bdrv_co_is_allocated(bs, sector_num, nb_sectors, pnum); -} - -/* Coroutine wrapper for bdrv_is_allocated() */ -static void coroutine_fn bdrv_is_allocated_co_entry(void *opaque) -{ - BdrvCoIsAllocatedData *data = opaque; - BlockDriverState *bs = data->bs; - - data->ret = bdrv_co_is_allocated(bs, data->sector_num, data->nb_sectors, - data->pnum); - data->done = true; -} - -/* - * Synchronous wrapper around bdrv_co_is_allocated(). - * - * See bdrv_co_is_allocated() for details. - */ -int bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num, int nb_sectors, - int *pnum) -{ - Coroutine *co; - BdrvCoIsAllocatedData data = { - .bs = bs, - .sector_num = sector_num, - .nb_sectors = nb_sectors, - .pnum = pnum, - .done = false, - }; - - co = qemu_coroutine_create(bdrv_is_allocated_co_entry); - qemu_coroutine_enter(co, &data); - while (!data.done) { - qemu_aio_wait(); - } - return data.ret; -} - -/* - * Given an image chain: ... -> [BASE] -> [INTER1] -> [INTER2] -> [TOP] - * - * Return true if the given sector is allocated in any image between - * BASE and TOP (inclusive). BASE can be NULL to check if the given - * sector is allocated in any image of the chain. Return false otherwise. - * - * 'pnum' is set to the number of sectors (including and immediately following - * the specified sector) that are known to be in the same - * allocated/unallocated state. - * - */ -int coroutine_fn bdrv_co_is_allocated_above(BlockDriverState *top, - BlockDriverState *base, - int64_t sector_num, - int nb_sectors, int *pnum) -{ - BlockDriverState *intermediate; - int ret, n = nb_sectors; - - intermediate = top; - while (intermediate && intermediate != base) { - int pnum_inter; - ret = bdrv_co_is_allocated(intermediate, sector_num, nb_sectors, - &pnum_inter); - if (ret < 0) { - return ret; - } else if (ret) { - *pnum = pnum_inter; - return 1; - } - - /* - * [sector_num, nb_sectors] is unallocated on top but intermediate - * might have - * - * [sector_num+x, nr_sectors] allocated. - */ - if (n > pnum_inter && - (intermediate == top || - sector_num + pnum_inter < intermediate->total_sectors)) { - n = pnum_inter; - } - - intermediate = intermediate->backing_hd; - } - - *pnum = n; - return 0; -} - -/* Coroutine wrapper for bdrv_is_allocated_above() */ -static void coroutine_fn bdrv_is_allocated_above_co_entry(void *opaque) -{ - BdrvCoIsAllocatedData *data = opaque; - BlockDriverState *top = data->bs; - BlockDriverState *base = data->base; - - data->ret = bdrv_co_is_allocated_above(top, base, data->sector_num, - data->nb_sectors, data->pnum); - data->done = true; -} - -/* - * Synchronous wrapper around bdrv_co_is_allocated_above(). - * - * See bdrv_co_is_allocated_above() for details. - */ -int bdrv_is_allocated_above(BlockDriverState *top, BlockDriverState *base, - int64_t sector_num, int nb_sectors, int *pnum) -{ - Coroutine *co; - BdrvCoIsAllocatedData data = { - .bs = top, - .base = base, - .sector_num = sector_num, - .nb_sectors = nb_sectors, - .pnum = pnum, - .done = false, - }; - - co = qemu_coroutine_create(bdrv_is_allocated_above_co_entry); - qemu_coroutine_enter(co, &data); - while (!data.done) { - qemu_aio_wait(); - } - return data.ret; -} - -const char *bdrv_get_encrypted_filename(BlockDriverState *bs) -{ - if (bs->backing_hd && bs->backing_hd->encrypted) - return bs->backing_file; - else if (bs->encrypted) - return bs->filename; - else - return NULL; -} - -void bdrv_get_backing_filename(BlockDriverState *bs, - char *filename, int filename_size) -{ - pstrcpy(filename, filename_size, bs->backing_file); -} - -int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num, - const uint8_t *buf, int nb_sectors) -{ - BlockDriver *drv = bs->drv; - if (!drv) - return -ENOMEDIUM; - if (!drv->bdrv_write_compressed) - return -ENOTSUP; - if (bdrv_check_request(bs, sector_num, nb_sectors)) - return -EIO; - - assert(!bs->dirty_bitmap); - - return drv->bdrv_write_compressed(bs, sector_num, buf, nb_sectors); -} - -int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) -{ - BlockDriver *drv = bs->drv; - if (!drv) - return -ENOMEDIUM; - if (!drv->bdrv_get_info) - return -ENOTSUP; - memset(bdi, 0, sizeof(*bdi)); - return drv->bdrv_get_info(bs, bdi); -} - -int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf, - int64_t pos, int size) -{ - QEMUIOVector qiov; - struct iovec iov = { - .iov_base = (void *) buf, - .iov_len = size, - }; - - qemu_iovec_init_external(&qiov, &iov, 1); - return bdrv_writev_vmstate(bs, &qiov, pos); -} - -int bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos) -{ - BlockDriver *drv = bs->drv; - - if (!drv) { - return -ENOMEDIUM; - } else if (drv->bdrv_save_vmstate) { - return drv->bdrv_save_vmstate(bs, qiov, pos); - } else if (bs->file) { - return bdrv_writev_vmstate(bs->file, qiov, pos); - } - - return -ENOTSUP; -} - -int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf, - int64_t pos, int size) -{ - BlockDriver *drv = bs->drv; - if (!drv) - return -ENOMEDIUM; - if (drv->bdrv_load_vmstate) - return drv->bdrv_load_vmstate(bs, buf, pos, size); - if (bs->file) - return bdrv_load_vmstate(bs->file, buf, pos, size); - return -ENOTSUP; -} - -void bdrv_debug_event(BlockDriverState *bs, BlkDebugEvent event) -{ - if (!bs || !bs->drv || !bs->drv->bdrv_debug_event) { - return; - } - - bs->drv->bdrv_debug_event(bs, event); -} - -int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event, - const char *tag) -{ - while (bs && bs->drv && !bs->drv->bdrv_debug_breakpoint) { - bs = bs->file; - } - - if (bs && bs->drv && bs->drv->bdrv_debug_breakpoint) { - return bs->drv->bdrv_debug_breakpoint(bs, event, tag); - } - - return -ENOTSUP; -} - -int bdrv_debug_resume(BlockDriverState *bs, const char *tag) -{ - while (bs && bs->drv && !bs->drv->bdrv_debug_resume) { - bs = bs->file; - } - - if (bs && bs->drv && bs->drv->bdrv_debug_resume) { - return bs->drv->bdrv_debug_resume(bs, tag); - } - - return -ENOTSUP; -} - -bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag) -{ - while (bs && bs->drv && !bs->drv->bdrv_debug_is_suspended) { - bs = bs->file; - } - - if (bs && bs->drv && bs->drv->bdrv_debug_is_suspended) { - return bs->drv->bdrv_debug_is_suspended(bs, tag); - } - - return false; -} - -int bdrv_is_snapshot(BlockDriverState *bs) -{ - return !!(bs->open_flags & BDRV_O_SNAPSHOT); -} - -/* backing_file can either be relative, or absolute, or a protocol. If it is - * relative, it must be relative to the chain. So, passing in bs->filename - * from a BDS as backing_file should not be done, as that may be relative to - * the CWD rather than the chain. */ -BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs, - const char *backing_file) -{ - char *filename_full = NULL; - char *backing_file_full = NULL; - char *filename_tmp = NULL; - int is_protocol = 0; - BlockDriverState *curr_bs = NULL; - BlockDriverState *retval = NULL; - - if (!bs || !bs->drv || !backing_file) { - return NULL; - } - - filename_full = g_malloc(PATH_MAX); - backing_file_full = g_malloc(PATH_MAX); - filename_tmp = g_malloc(PATH_MAX); - - is_protocol = path_has_protocol(backing_file); - - for (curr_bs = bs; curr_bs->backing_hd; curr_bs = curr_bs->backing_hd) { - - /* If either of the filename paths is actually a protocol, then - * compare unmodified paths; otherwise make paths relative */ - if (is_protocol || path_has_protocol(curr_bs->backing_file)) { - if (strcmp(backing_file, curr_bs->backing_file) == 0) { - retval = curr_bs->backing_hd; - break; - } - } else { - /* If not an absolute filename path, make it relative to the current - * image's filename path */ - path_combine(filename_tmp, PATH_MAX, curr_bs->filename, - backing_file); - - /* We are going to compare absolute pathnames */ - if (!realpath(filename_tmp, filename_full)) { - continue; - } - - /* We need to make sure the backing filename we are comparing against - * is relative to the current image filename (or absolute) */ - path_combine(filename_tmp, PATH_MAX, curr_bs->filename, - curr_bs->backing_file); - - if (!realpath(filename_tmp, backing_file_full)) { - continue; - } - - if (strcmp(backing_file_full, filename_full) == 0) { - retval = curr_bs->backing_hd; - break; - } - } - } - - g_free(filename_full); - g_free(backing_file_full); - g_free(filename_tmp); - return retval; -} - -int bdrv_get_backing_file_depth(BlockDriverState *bs) -{ - if (!bs->drv) { - return 0; - } - - if (!bs->backing_hd) { - return 0; - } - - return 1 + bdrv_get_backing_file_depth(bs->backing_hd); -} - -BlockDriverState *bdrv_find_base(BlockDriverState *bs) -{ - BlockDriverState *curr_bs = NULL; - - if (!bs) { - return NULL; - } - - curr_bs = bs; - - while (curr_bs->backing_hd) { - curr_bs = curr_bs->backing_hd; - } - return curr_bs; -} - -/**************************************************************/ -/* async I/Os */ - -BlockDriverAIOCB *bdrv_aio_readv(BlockDriverState *bs, int64_t sector_num, - QEMUIOVector *qiov, int nb_sectors, - BlockDriverCompletionFunc *cb, void *opaque) -{ - trace_bdrv_aio_readv(bs, sector_num, nb_sectors, opaque); - - return bdrv_co_aio_rw_vector(bs, sector_num, qiov, nb_sectors, - cb, opaque, false); -} - -BlockDriverAIOCB *bdrv_aio_writev(BlockDriverState *bs, int64_t sector_num, - QEMUIOVector *qiov, int nb_sectors, - BlockDriverCompletionFunc *cb, void *opaque) -{ - trace_bdrv_aio_writev(bs, sector_num, nb_sectors, opaque); - - return bdrv_co_aio_rw_vector(bs, sector_num, qiov, nb_sectors, - cb, opaque, true); -} - - -typedef struct MultiwriteCB { - int error; - int num_requests; - int num_callbacks; - struct { - BlockDriverCompletionFunc *cb; - void *opaque; - QEMUIOVector *free_qiov; - } callbacks[]; -} MultiwriteCB; - -static void multiwrite_user_cb(MultiwriteCB *mcb) -{ - int i; - - for (i = 0; i < mcb->num_callbacks; i++) { - mcb->callbacks[i].cb(mcb->callbacks[i].opaque, mcb->error); - if (mcb->callbacks[i].free_qiov) { - qemu_iovec_destroy(mcb->callbacks[i].free_qiov); - } - g_free(mcb->callbacks[i].free_qiov); - } -} - -static void multiwrite_cb(void *opaque, int ret) -{ - MultiwriteCB *mcb = opaque; - - trace_multiwrite_cb(mcb, ret); - - if (ret < 0 && !mcb->error) { - mcb->error = ret; - } - - mcb->num_requests--; - if (mcb->num_requests == 0) { - multiwrite_user_cb(mcb); - g_free(mcb); - } -} - -static int multiwrite_req_compare(const void *a, const void *b) -{ - const BlockRequest *req1 = a, *req2 = b; - - /* - * Note that we can't simply subtract req2->sector from req1->sector - * here as that could overflow the return value. - */ - if (req1->sector > req2->sector) { - return 1; - } else if (req1->sector < req2->sector) { - return -1; - } else { - return 0; - } -} - -/* - * Takes a bunch of requests and tries to merge them. Returns the number of - * requests that remain after merging. - */ -static int multiwrite_merge(BlockDriverState *bs, BlockRequest *reqs, - int num_reqs, MultiwriteCB *mcb) -{ - int i, outidx; - - // Sort requests by start sector - qsort(reqs, num_reqs, sizeof(*reqs), &multiwrite_req_compare); - - // Check if adjacent requests touch the same clusters. If so, combine them, - // filling up gaps with zero sectors. - outidx = 0; - for (i = 1; i < num_reqs; i++) { - int merge = 0; - int64_t oldreq_last = reqs[outidx].sector + reqs[outidx].nb_sectors; - - // Handle exactly sequential writes and overlapping writes. - if (reqs[i].sector <= oldreq_last) { - merge = 1; - } - - if (reqs[outidx].qiov->niov + reqs[i].qiov->niov + 1 > IOV_MAX) { - merge = 0; - } - - if (merge) { - size_t size; - QEMUIOVector *qiov = g_malloc0(sizeof(*qiov)); - qemu_iovec_init(qiov, - reqs[outidx].qiov->niov + reqs[i].qiov->niov + 1); - - // Add the first request to the merged one. If the requests are - // overlapping, drop the last sectors of the first request. - size = (reqs[i].sector - reqs[outidx].sector) << 9; - qemu_iovec_concat(qiov, reqs[outidx].qiov, 0, size); - - // We should need to add any zeros between the two requests - assert (reqs[i].sector <= oldreq_last); - - // Add the second request - qemu_iovec_concat(qiov, reqs[i].qiov, 0, reqs[i].qiov->size); - - reqs[outidx].nb_sectors = qiov->size >> 9; - reqs[outidx].qiov = qiov; - - mcb->callbacks[i].free_qiov = reqs[outidx].qiov; - } else { - outidx++; - reqs[outidx].sector = reqs[i].sector; - reqs[outidx].nb_sectors = reqs[i].nb_sectors; - reqs[outidx].qiov = reqs[i].qiov; - } - } - - return outidx + 1; -} - -/* - * Submit multiple AIO write requests at once. - * - * On success, the function returns 0 and all requests in the reqs array have - * been submitted. In error case this function returns -1, and any of the - * requests may or may not be submitted yet. In particular, this means that the - * callback will be called for some of the requests, for others it won't. The - * caller must check the error field of the BlockRequest to wait for the right - * callbacks (if error != 0, no callback will be called). - * - * The implementation may modify the contents of the reqs array, e.g. to merge - * requests. However, the fields opaque and error are left unmodified as they - * are used to signal failure for a single request to the caller. - */ -int bdrv_aio_multiwrite(BlockDriverState *bs, BlockRequest *reqs, int num_reqs) -{ - MultiwriteCB *mcb; - int i; - - /* don't submit writes if we don't have a medium */ - if (bs->drv == NULL) { - for (i = 0; i < num_reqs; i++) { - reqs[i].error = -ENOMEDIUM; - } - return -1; - } - - if (num_reqs == 0) { - return 0; - } - - // Create MultiwriteCB structure - mcb = g_malloc0(sizeof(*mcb) + num_reqs * sizeof(*mcb->callbacks)); - mcb->num_requests = 0; - mcb->num_callbacks = num_reqs; - - for (i = 0; i < num_reqs; i++) { - mcb->callbacks[i].cb = reqs[i].cb; - mcb->callbacks[i].opaque = reqs[i].opaque; - } - - // Check for mergable requests - num_reqs = multiwrite_merge(bs, reqs, num_reqs, mcb); - - trace_bdrv_aio_multiwrite(mcb, mcb->num_callbacks, num_reqs); - - /* Run the aio requests. */ - mcb->num_requests = num_reqs; - for (i = 0; i < num_reqs; i++) { - bdrv_aio_writev(bs, reqs[i].sector, reqs[i].qiov, - reqs[i].nb_sectors, multiwrite_cb, mcb); - } - - return 0; -} - -void bdrv_aio_cancel(BlockDriverAIOCB *acb) -{ - acb->aiocb_info->cancel(acb); -} - -/* block I/O throttling */ -static bool bdrv_exceed_bps_limits(BlockDriverState *bs, int nb_sectors, - bool is_write, double elapsed_time, uint64_t *wait) -{ - uint64_t bps_limit = 0; - uint64_t extension; - double bytes_limit, bytes_base, bytes_res; - double slice_time, wait_time; - - if (bs->io_limits.bps[BLOCK_IO_LIMIT_TOTAL]) { - bps_limit = bs->io_limits.bps[BLOCK_IO_LIMIT_TOTAL]; - } else if (bs->io_limits.bps[is_write]) { - bps_limit = bs->io_limits.bps[is_write]; - } else { - if (wait) { - *wait = 0; - } - - return false; - } - - slice_time = bs->slice_end - bs->slice_start; - slice_time /= (NANOSECONDS_PER_SECOND); - bytes_limit = bps_limit * slice_time; - bytes_base = bs->slice_submitted.bytes[is_write]; - if (bs->io_limits.bps[BLOCK_IO_LIMIT_TOTAL]) { - bytes_base += bs->slice_submitted.bytes[!is_write]; - } - - /* bytes_base: the bytes of data which have been read/written; and - * it is obtained from the history statistic info. - * bytes_res: the remaining bytes of data which need to be read/written. - * (bytes_base + bytes_res) / bps_limit: used to calcuate - * the total time for completing reading/writting all data. - */ - bytes_res = (unsigned) nb_sectors * BDRV_SECTOR_SIZE; - - if (bytes_base + bytes_res <= bytes_limit) { - if (wait) { - *wait = 0; - } - - return false; - } - - /* Calc approx time to dispatch */ - wait_time = (bytes_base + bytes_res) / bps_limit - elapsed_time; - - /* When the I/O rate at runtime exceeds the limits, - * bs->slice_end need to be extended in order that the current statistic - * info can be kept until the timer fire, so it is increased and tuned - * based on the result of experiment. - */ - extension = wait_time * NANOSECONDS_PER_SECOND; - extension = DIV_ROUND_UP(extension, BLOCK_IO_SLICE_TIME) * - BLOCK_IO_SLICE_TIME; - bs->slice_end += extension; - if (wait) { - *wait = wait_time * NANOSECONDS_PER_SECOND; - } - - return true; -} - -static bool bdrv_exceed_iops_limits(BlockDriverState *bs, bool is_write, - double elapsed_time, uint64_t *wait) -{ - uint64_t iops_limit = 0; - double ios_limit, ios_base; - double slice_time, wait_time; - - if (bs->io_limits.iops[BLOCK_IO_LIMIT_TOTAL]) { - iops_limit = bs->io_limits.iops[BLOCK_IO_LIMIT_TOTAL]; - } else if (bs->io_limits.iops[is_write]) { - iops_limit = bs->io_limits.iops[is_write]; - } else { - if (wait) { - *wait = 0; - } - - return false; - } - - slice_time = bs->slice_end - bs->slice_start; - slice_time /= (NANOSECONDS_PER_SECOND); - ios_limit = iops_limit * slice_time; - ios_base = bs->slice_submitted.ios[is_write]; - if (bs->io_limits.iops[BLOCK_IO_LIMIT_TOTAL]) { - ios_base += bs->slice_submitted.ios[!is_write]; - } - - if (ios_base + 1 <= ios_limit) { - if (wait) { - *wait = 0; - } - - return false; - } - - /* Calc approx time to dispatch, in seconds */ - wait_time = (ios_base + 1) / iops_limit; - if (wait_time > elapsed_time) { - wait_time = wait_time - elapsed_time; - } else { - wait_time = 0; - } - - /* Exceeded current slice, extend it by another slice time */ - bs->slice_end += BLOCK_IO_SLICE_TIME; - if (wait) { - *wait = wait_time * NANOSECONDS_PER_SECOND; - } - - return true; -} - -static bool bdrv_exceed_io_limits(BlockDriverState *bs, int nb_sectors, - bool is_write, int64_t *wait) -{ - int64_t now, max_wait; - uint64_t bps_wait = 0, iops_wait = 0; - double elapsed_time; - int bps_ret, iops_ret; - - now = qemu_get_clock_ns(vm_clock); - if (now > bs->slice_end) { - bs->slice_start = now; - bs->slice_end = now + BLOCK_IO_SLICE_TIME; - memset(&bs->slice_submitted, 0, sizeof(bs->slice_submitted)); - } - - elapsed_time = now - bs->slice_start; - elapsed_time /= (NANOSECONDS_PER_SECOND); - - bps_ret = bdrv_exceed_bps_limits(bs, nb_sectors, - is_write, elapsed_time, &bps_wait); - iops_ret = bdrv_exceed_iops_limits(bs, is_write, - elapsed_time, &iops_wait); - if (bps_ret || iops_ret) { - max_wait = bps_wait > iops_wait ? bps_wait : iops_wait; - if (wait) { - *wait = max_wait; - } - - now = qemu_get_clock_ns(vm_clock); - if (bs->slice_end < now + max_wait) { - bs->slice_end = now + max_wait; - } - - return true; - } - - if (wait) { - *wait = 0; - } - - bs->slice_submitted.bytes[is_write] += (int64_t)nb_sectors * - BDRV_SECTOR_SIZE; - bs->slice_submitted.ios[is_write]++; - - return false; -} - -/**************************************************************/ -/* async block device emulation */ - -typedef struct BlockDriverAIOCBSync { - BlockDriverAIOCB common; - QEMUBH *bh; - int ret; - /* vector translation state */ - QEMUIOVector *qiov; - uint8_t *bounce; - int is_write; -} BlockDriverAIOCBSync; - -static void bdrv_aio_cancel_em(BlockDriverAIOCB *blockacb) -{ - BlockDriverAIOCBSync *acb = - container_of(blockacb, BlockDriverAIOCBSync, common); - qemu_bh_delete(acb->bh); - acb->bh = NULL; - qemu_aio_release(acb); -} - -static const AIOCBInfo bdrv_em_aiocb_info = { - .aiocb_size = sizeof(BlockDriverAIOCBSync), - .cancel = bdrv_aio_cancel_em, -}; - -static void bdrv_aio_bh_cb(void *opaque) -{ - BlockDriverAIOCBSync *acb = opaque; - - if (!acb->is_write) - qemu_iovec_from_buf(acb->qiov, 0, acb->bounce, acb->qiov->size); - qemu_vfree(acb->bounce); - acb->common.cb(acb->common.opaque, acb->ret); - qemu_bh_delete(acb->bh); - acb->bh = NULL; - qemu_aio_release(acb); -} - -static BlockDriverAIOCB *bdrv_aio_rw_vector(BlockDriverState *bs, - int64_t sector_num, - QEMUIOVector *qiov, - int nb_sectors, - BlockDriverCompletionFunc *cb, - void *opaque, - int is_write) - -{ - BlockDriverAIOCBSync *acb; - - acb = qemu_aio_get(&bdrv_em_aiocb_info, bs, cb, opaque); - acb->is_write = is_write; - acb->qiov = qiov; - acb->bounce = qemu_blockalign(bs, qiov->size); - acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb); - - if (is_write) { - qemu_iovec_to_buf(acb->qiov, 0, acb->bounce, qiov->size); - acb->ret = bs->drv->bdrv_write(bs, sector_num, acb->bounce, nb_sectors); - } else { - acb->ret = bs->drv->bdrv_read(bs, sector_num, acb->bounce, nb_sectors); - } - - qemu_bh_schedule(acb->bh); - - return &acb->common; -} - -static BlockDriverAIOCB *bdrv_aio_readv_em(BlockDriverState *bs, - int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, - BlockDriverCompletionFunc *cb, void *opaque) -{ - return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 0); -} - -static BlockDriverAIOCB *bdrv_aio_writev_em(BlockDriverState *bs, - int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, - BlockDriverCompletionFunc *cb, void *opaque) -{ - return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 1); -} - - -typedef struct BlockDriverAIOCBCoroutine { - BlockDriverAIOCB common; - BlockRequest req; - bool is_write; - bool *done; - QEMUBH* bh; -} BlockDriverAIOCBCoroutine; - -static void bdrv_aio_co_cancel_em(BlockDriverAIOCB *blockacb) -{ - BlockDriverAIOCBCoroutine *acb = - container_of(blockacb, BlockDriverAIOCBCoroutine, common); - bool done = false; - - acb->done = &done; - while (!done) { - qemu_aio_wait(); - } -} - -static const AIOCBInfo bdrv_em_co_aiocb_info = { - .aiocb_size = sizeof(BlockDriverAIOCBCoroutine), - .cancel = bdrv_aio_co_cancel_em, -}; - -static void bdrv_co_em_bh(void *opaque) -{ - BlockDriverAIOCBCoroutine *acb = opaque; - - acb->common.cb(acb->common.opaque, acb->req.error); - - if (acb->done) { - *acb->done = true; - } - - qemu_bh_delete(acb->bh); - qemu_aio_release(acb); -} - -/* Invoke bdrv_co_do_readv/bdrv_co_do_writev */ -static void coroutine_fn bdrv_co_do_rw(void *opaque) -{ - BlockDriverAIOCBCoroutine *acb = opaque; - BlockDriverState *bs = acb->common.bs; - - if (!acb->is_write) { - acb->req.error = bdrv_co_do_readv(bs, acb->req.sector, - acb->req.nb_sectors, acb->req.qiov, 0); - } else { - acb->req.error = bdrv_co_do_writev(bs, acb->req.sector, - acb->req.nb_sectors, acb->req.qiov, 0); - } - - acb->bh = qemu_bh_new(bdrv_co_em_bh, acb); - qemu_bh_schedule(acb->bh); -} - -static BlockDriverAIOCB *bdrv_co_aio_rw_vector(BlockDriverState *bs, - int64_t sector_num, - QEMUIOVector *qiov, - int nb_sectors, - BlockDriverCompletionFunc *cb, - void *opaque, - bool is_write) -{ - Coroutine *co; - BlockDriverAIOCBCoroutine *acb; - - acb = qemu_aio_get(&bdrv_em_co_aiocb_info, bs, cb, opaque); - acb->req.sector = sector_num; - acb->req.nb_sectors = nb_sectors; - acb->req.qiov = qiov; - acb->is_write = is_write; - acb->done = NULL; - - co = qemu_coroutine_create(bdrv_co_do_rw); - qemu_coroutine_enter(co, acb); - - return &acb->common; -} - -static void coroutine_fn bdrv_aio_flush_co_entry(void *opaque) -{ - BlockDriverAIOCBCoroutine *acb = opaque; - BlockDriverState *bs = acb->common.bs; - - acb->req.error = bdrv_co_flush(bs); - acb->bh = qemu_bh_new(bdrv_co_em_bh, acb); - qemu_bh_schedule(acb->bh); -} - -BlockDriverAIOCB *bdrv_aio_flush(BlockDriverState *bs, - BlockDriverCompletionFunc *cb, void *opaque) -{ - trace_bdrv_aio_flush(bs, opaque); - - Coroutine *co; - BlockDriverAIOCBCoroutine *acb; - - acb = qemu_aio_get(&bdrv_em_co_aiocb_info, bs, cb, opaque); - acb->done = NULL; - - co = qemu_coroutine_create(bdrv_aio_flush_co_entry); - qemu_coroutine_enter(co, acb); - - return &acb->common; -} - -static void coroutine_fn bdrv_aio_discard_co_entry(void *opaque) -{ - BlockDriverAIOCBCoroutine *acb = opaque; - BlockDriverState *bs = acb->common.bs; - - acb->req.error = bdrv_co_discard(bs, acb->req.sector, acb->req.nb_sectors); - acb->bh = qemu_bh_new(bdrv_co_em_bh, acb); - qemu_bh_schedule(acb->bh); -} - -BlockDriverAIOCB *bdrv_aio_discard(BlockDriverState *bs, - int64_t sector_num, int nb_sectors, - BlockDriverCompletionFunc *cb, void *opaque) -{ - Coroutine *co; - BlockDriverAIOCBCoroutine *acb; - - trace_bdrv_aio_discard(bs, sector_num, nb_sectors, opaque); - - acb = qemu_aio_get(&bdrv_em_co_aiocb_info, bs, cb, opaque); - acb->req.sector = sector_num; - acb->req.nb_sectors = nb_sectors; - acb->done = NULL; - co = qemu_coroutine_create(bdrv_aio_discard_co_entry); - qemu_coroutine_enter(co, acb); - - return &acb->common; -} - -void bdrv_init(void) -{ - module_call_init(MODULE_INIT_BLOCK); -} - -void bdrv_init_with_whitelist(void) -{ - use_bdrv_whitelist = 1; - bdrv_init(); -} - -void *qemu_aio_get(const AIOCBInfo *aiocb_info, BlockDriverState *bs, - BlockDriverCompletionFunc *cb, void *opaque) -{ - BlockDriverAIOCB *acb; - - acb = g_slice_alloc(aiocb_info->aiocb_size); - acb->aiocb_info = aiocb_info; - acb->bs = bs; - acb->cb = cb; - acb->opaque = opaque; - return acb; -} - -void qemu_aio_release(void *p) -{ - BlockDriverAIOCB *acb = p; - g_slice_free1(acb->aiocb_info->aiocb_size, acb); -} - -/**************************************************************/ -/* Coroutine block device emulation */ - -typedef struct CoroutineIOCompletion { - Coroutine *coroutine; - int ret; -} CoroutineIOCompletion; - -static void bdrv_co_io_em_complete(void *opaque, int ret) -{ - CoroutineIOCompletion *co = opaque; - - co->ret = ret; - qemu_coroutine_enter(co->coroutine, NULL); -} - -static int coroutine_fn bdrv_co_io_em(BlockDriverState *bs, int64_t sector_num, - int nb_sectors, QEMUIOVector *iov, - bool is_write) -{ - CoroutineIOCompletion co = { - .coroutine = qemu_coroutine_self(), - }; - BlockDriverAIOCB *acb; - - if (is_write) { - acb = bs->drv->bdrv_aio_writev(bs, sector_num, iov, nb_sectors, - bdrv_co_io_em_complete, &co); - } else { - acb = bs->drv->bdrv_aio_readv(bs, sector_num, iov, nb_sectors, - bdrv_co_io_em_complete, &co); - } - - trace_bdrv_co_io_em(bs, sector_num, nb_sectors, is_write, acb); - if (!acb) { - return -EIO; - } - qemu_coroutine_yield(); - - return co.ret; -} - -static int coroutine_fn bdrv_co_readv_em(BlockDriverState *bs, - int64_t sector_num, int nb_sectors, - QEMUIOVector *iov) -{ - return bdrv_co_io_em(bs, sector_num, nb_sectors, iov, false); -} - -static int coroutine_fn bdrv_co_writev_em(BlockDriverState *bs, - int64_t sector_num, int nb_sectors, - QEMUIOVector *iov) -{ - return bdrv_co_io_em(bs, sector_num, nb_sectors, iov, true); -} - -static void coroutine_fn bdrv_flush_co_entry(void *opaque) -{ - RwCo *rwco = opaque; - - rwco->ret = bdrv_co_flush(rwco->bs); -} - -int coroutine_fn bdrv_co_flush(BlockDriverState *bs) -{ - int ret; - - if (!bs || !bdrv_is_inserted(bs) || bdrv_is_read_only(bs)) { - return 0; - } - - /* Write back cached data to the OS even with cache=unsafe */ - BLKDBG_EVENT(bs->file, BLKDBG_FLUSH_TO_OS); - if (bs->drv->bdrv_co_flush_to_os) { - ret = bs->drv->bdrv_co_flush_to_os(bs); - if (ret < 0) { - return ret; - } - } - - /* But don't actually force it to the disk with cache=unsafe */ - if (bs->open_flags & BDRV_O_NO_FLUSH) { - goto flush_parent; - } - - BLKDBG_EVENT(bs->file, BLKDBG_FLUSH_TO_DISK); - if (bs->drv->bdrv_co_flush_to_disk) { - ret = bs->drv->bdrv_co_flush_to_disk(bs); - } else if (bs->drv->bdrv_aio_flush) { - BlockDriverAIOCB *acb; - CoroutineIOCompletion co = { - .coroutine = qemu_coroutine_self(), - }; - - acb = bs->drv->bdrv_aio_flush(bs, bdrv_co_io_em_complete, &co); - if (acb == NULL) { - ret = -EIO; - } else { - qemu_coroutine_yield(); - ret = co.ret; - } - } else { - /* - * Some block drivers always operate in either writethrough or unsafe - * mode and don't support bdrv_flush therefore. Usually qemu doesn't - * know how the server works (because the behaviour is hardcoded or - * depends on server-side configuration), so we can't ensure that - * everything is safe on disk. Returning an error doesn't work because - * that would break guests even if the server operates in writethrough - * mode. - * - * Let's hope the user knows what he's doing. - */ - ret = 0; - } - if (ret < 0) { - return ret; - } - - /* Now flush the underlying protocol. It will also have BDRV_O_NO_FLUSH - * in the case of cache=unsafe, so there are no useless flushes. - */ -flush_parent: - return bdrv_co_flush(bs->file); -} - -void bdrv_invalidate_cache(BlockDriverState *bs) -{ - if (bs->drv && bs->drv->bdrv_invalidate_cache) { - bs->drv->bdrv_invalidate_cache(bs); - } -} - -void bdrv_invalidate_cache_all(void) -{ - BlockDriverState *bs; - - QTAILQ_FOREACH(bs, &bdrv_states, list) { - bdrv_invalidate_cache(bs); - } -} - -void bdrv_clear_incoming_migration_all(void) -{ - BlockDriverState *bs; - - QTAILQ_FOREACH(bs, &bdrv_states, list) { - bs->open_flags = bs->open_flags & ~(BDRV_O_INCOMING); - } -} - -int bdrv_flush(BlockDriverState *bs) -{ - Coroutine *co; - RwCo rwco = { - .bs = bs, - .ret = NOT_DONE, - }; - - if (qemu_in_coroutine()) { - /* Fast-path if already in coroutine context */ - bdrv_flush_co_entry(&rwco); - } else { - co = qemu_coroutine_create(bdrv_flush_co_entry); - qemu_coroutine_enter(co, &rwco); - while (rwco.ret == NOT_DONE) { - qemu_aio_wait(); - } - } - - return rwco.ret; -} - -static void coroutine_fn bdrv_discard_co_entry(void *opaque) -{ - RwCo *rwco = opaque; - - rwco->ret = bdrv_co_discard(rwco->bs, rwco->sector_num, rwco->nb_sectors); -} - -int coroutine_fn bdrv_co_discard(BlockDriverState *bs, int64_t sector_num, - int nb_sectors) -{ - if (!bs->drv) { - return -ENOMEDIUM; - } else if (bdrv_check_request(bs, sector_num, nb_sectors)) { - return -EIO; - } else if (bs->read_only) { - return -EROFS; - } - - if (bs->dirty_bitmap) { - bdrv_reset_dirty(bs, sector_num, nb_sectors); - } - - /* Do nothing if disabled. */ - if (!(bs->open_flags & BDRV_O_UNMAP)) { - return 0; - } - - if (bs->drv->bdrv_co_discard) { - return bs->drv->bdrv_co_discard(bs, sector_num, nb_sectors); - } else if (bs->drv->bdrv_aio_discard) { - BlockDriverAIOCB *acb; - CoroutineIOCompletion co = { - .coroutine = qemu_coroutine_self(), - }; - - acb = bs->drv->bdrv_aio_discard(bs, sector_num, nb_sectors, - bdrv_co_io_em_complete, &co); - if (acb == NULL) { - return -EIO; - } else { - qemu_coroutine_yield(); - return co.ret; - } - } else { - return 0; - } -} - -int bdrv_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors) -{ - Coroutine *co; - RwCo rwco = { - .bs = bs, - .sector_num = sector_num, - .nb_sectors = nb_sectors, - .ret = NOT_DONE, - }; - - if (qemu_in_coroutine()) { - /* Fast-path if already in coroutine context */ - bdrv_discard_co_entry(&rwco); - } else { - co = qemu_coroutine_create(bdrv_discard_co_entry); - qemu_coroutine_enter(co, &rwco); - while (rwco.ret == NOT_DONE) { - qemu_aio_wait(); - } - } - - return rwco.ret; -} - -/**************************************************************/ -/* removable device support */ - -/** - * Return TRUE if the media is present - */ -int bdrv_is_inserted(BlockDriverState *bs) -{ - BlockDriver *drv = bs->drv; - - if (!drv) - return 0; - if (!drv->bdrv_is_inserted) - return 1; - return drv->bdrv_is_inserted(bs); -} - -/** - * Return whether the media changed since the last call to this - * function, or -ENOTSUP if we don't know. Most drivers don't know. - */ -int bdrv_media_changed(BlockDriverState *bs) -{ - BlockDriver *drv = bs->drv; - - if (drv && drv->bdrv_media_changed) { - return drv->bdrv_media_changed(bs); - } - return -ENOTSUP; -} - -/** - * If eject_flag is TRUE, eject the media. Otherwise, close the tray - */ -void bdrv_eject(BlockDriverState *bs, bool eject_flag) -{ - BlockDriver *drv = bs->drv; - - if (drv && drv->bdrv_eject) { - drv->bdrv_eject(bs, eject_flag); - } - - if (bs->device_name[0] != '\0') { - bdrv_emit_qmp_eject_event(bs, eject_flag); - } -} - -/** - * Lock or unlock the media (if it is locked, the user won't be able - * to eject it manually). - */ -void bdrv_lock_medium(BlockDriverState *bs, bool locked) -{ - BlockDriver *drv = bs->drv; - - trace_bdrv_lock_medium(bs, locked); - - if (drv && drv->bdrv_lock_medium) { - drv->bdrv_lock_medium(bs, locked); - } -} - -/* needed for generic scsi interface */ - -int bdrv_ioctl(BlockDriverState *bs, unsigned long int req, void *buf) -{ - BlockDriver *drv = bs->drv; - - if (drv && drv->bdrv_ioctl) - return drv->bdrv_ioctl(bs, req, buf); - return -ENOTSUP; -} - -BlockDriverAIOCB *bdrv_aio_ioctl(BlockDriverState *bs, - unsigned long int req, void *buf, - BlockDriverCompletionFunc *cb, void *opaque) -{ - BlockDriver *drv = bs->drv; - - if (drv && drv->bdrv_aio_ioctl) - return drv->bdrv_aio_ioctl(bs, req, buf, cb, opaque); - return NULL; -} - -void bdrv_set_buffer_alignment(BlockDriverState *bs, int align) -{ - bs->buffer_alignment = align; -} - -void *qemu_blockalign(BlockDriverState *bs, size_t size) -{ - return qemu_memalign((bs && bs->buffer_alignment) ? bs->buffer_alignment : 512, size); -} - -/* - * Check if all memory in this vector is sector aligned. - */ -bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov) -{ - int i; - - for (i = 0; i < qiov->niov; i++) { - if ((uintptr_t) qiov->iov[i].iov_base % bs->buffer_alignment) { - return false; - } - } - - return true; -} - -void bdrv_set_dirty_tracking(BlockDriverState *bs, int granularity) -{ - int64_t bitmap_size; - - assert((granularity & (granularity - 1)) == 0); - - if (granularity) { - granularity >>= BDRV_SECTOR_BITS; - assert(!bs->dirty_bitmap); - bitmap_size = (bdrv_getlength(bs) >> BDRV_SECTOR_BITS); - bs->dirty_bitmap = hbitmap_alloc(bitmap_size, ffs(granularity) - 1); - } else { - if (bs->dirty_bitmap) { - hbitmap_free(bs->dirty_bitmap); - bs->dirty_bitmap = NULL; - } - } -} - -int bdrv_get_dirty(BlockDriverState *bs, int64_t sector) -{ - if (bs->dirty_bitmap) { - return hbitmap_get(bs->dirty_bitmap, sector); - } else { - return 0; - } -} - -void bdrv_dirty_iter_init(BlockDriverState *bs, HBitmapIter *hbi) -{ - hbitmap_iter_init(hbi, bs->dirty_bitmap, 0); -} - -void bdrv_set_dirty(BlockDriverState *bs, int64_t cur_sector, - int nr_sectors) -{ - hbitmap_set(bs->dirty_bitmap, cur_sector, nr_sectors); -} - -void bdrv_reset_dirty(BlockDriverState *bs, int64_t cur_sector, - int nr_sectors) -{ - hbitmap_reset(bs->dirty_bitmap, cur_sector, nr_sectors); -} - -int64_t bdrv_get_dirty_count(BlockDriverState *bs) -{ - if (bs->dirty_bitmap) { - return hbitmap_count(bs->dirty_bitmap); - } else { - return 0; - } -} - -void bdrv_set_in_use(BlockDriverState *bs, int in_use) -{ - assert(bs->in_use != in_use); - bs->in_use = in_use; -} - -int bdrv_in_use(BlockDriverState *bs) -{ - return bs->in_use; -} - -void bdrv_iostatus_enable(BlockDriverState *bs) -{ - bs->iostatus_enabled = true; - bs->iostatus = BLOCK_DEVICE_IO_STATUS_OK; -} - -/* The I/O status is only enabled if the drive explicitly - * enables it _and_ the VM is configured to stop on errors */ -bool bdrv_iostatus_is_enabled(const BlockDriverState *bs) -{ - return (bs->iostatus_enabled && - (bs->on_write_error == BLOCKDEV_ON_ERROR_ENOSPC || - bs->on_write_error == BLOCKDEV_ON_ERROR_STOP || - bs->on_read_error == BLOCKDEV_ON_ERROR_STOP)); -} - -void bdrv_iostatus_disable(BlockDriverState *bs) -{ - bs->iostatus_enabled = false; -} - -void bdrv_iostatus_reset(BlockDriverState *bs) -{ - if (bdrv_iostatus_is_enabled(bs)) { - bs->iostatus = BLOCK_DEVICE_IO_STATUS_OK; - if (bs->job) { - block_job_iostatus_reset(bs->job); - } - } -} - -void bdrv_iostatus_set_err(BlockDriverState *bs, int error) -{ - assert(bdrv_iostatus_is_enabled(bs)); - if (bs->iostatus == BLOCK_DEVICE_IO_STATUS_OK) { - bs->iostatus = error == ENOSPC ? BLOCK_DEVICE_IO_STATUS_NOSPACE : - BLOCK_DEVICE_IO_STATUS_FAILED; - } -} - -void -bdrv_acct_start(BlockDriverState *bs, BlockAcctCookie *cookie, int64_t bytes, - enum BlockAcctType type) -{ - assert(type < BDRV_MAX_IOTYPE); - - cookie->bytes = bytes; - cookie->start_time_ns = get_clock(); - cookie->type = type; -} - -void -bdrv_acct_done(BlockDriverState *bs, BlockAcctCookie *cookie) -{ - assert(cookie->type < BDRV_MAX_IOTYPE); - - bs->nr_bytes[cookie->type] += cookie->bytes; - bs->nr_ops[cookie->type]++; - bs->total_time_ns[cookie->type] += get_clock() - cookie->start_time_ns; -} - -void bdrv_img_create(const char *filename, const char *fmt, - const char *base_filename, const char *base_fmt, - char *options, uint64_t img_size, int flags, - Error **errp, bool quiet) -{ - QEMUOptionParameter *param = NULL, *create_options = NULL; - QEMUOptionParameter *backing_fmt, *backing_file, *size; - BlockDriverState *bs = NULL; - BlockDriver *drv, *proto_drv; - BlockDriver *backing_drv = NULL; - int ret = 0; - - /* Find driver and parse its options */ - drv = bdrv_find_format(fmt); - if (!drv) { - error_setg(errp, "Unknown file format '%s'", fmt); - return; - } - - proto_drv = bdrv_find_protocol(filename, true); - if (!proto_drv) { - error_setg(errp, "Unknown protocol '%s'", filename); - return; - } - - create_options = append_option_parameters(create_options, - drv->create_options); - create_options = append_option_parameters(create_options, - proto_drv->create_options); - - /* Create parameter list with default values */ - param = parse_option_parameters("", create_options, param); - - set_option_parameter_int(param, BLOCK_OPT_SIZE, img_size); - - /* Parse -o options */ - if (options) { - param = parse_option_parameters(options, create_options, param); - if (param == NULL) { - error_setg(errp, "Invalid options for file format '%s'.", fmt); - goto out; - } - } - - if (base_filename) { - if (set_option_parameter(param, BLOCK_OPT_BACKING_FILE, - base_filename)) { - error_setg(errp, "Backing file not supported for file format '%s'", - fmt); - goto out; - } - } - - if (base_fmt) { - if (set_option_parameter(param, BLOCK_OPT_BACKING_FMT, base_fmt)) { - error_setg(errp, "Backing file format not supported for file " - "format '%s'", fmt); - goto out; - } - } - - backing_file = get_option_parameter(param, BLOCK_OPT_BACKING_FILE); - if (backing_file && backing_file->value.s) { - if (!strcmp(filename, backing_file->value.s)) { - error_setg(errp, "Error: Trying to create an image with the " - "same filename as the backing file"); - goto out; - } - } - - backing_fmt = get_option_parameter(param, BLOCK_OPT_BACKING_FMT); - if (backing_fmt && backing_fmt->value.s) { - backing_drv = bdrv_find_format(backing_fmt->value.s); - if (!backing_drv) { - error_setg(errp, "Unknown backing file format '%s'", - backing_fmt->value.s); - goto out; - } - } - - // The size for the image must always be specified, with one exception: - // If we are using a backing file, we can obtain the size from there - size = get_option_parameter(param, BLOCK_OPT_SIZE); - if (size && size->value.n == -1) { - if (backing_file && backing_file->value.s) { - uint64_t size; - char buf[32]; - int back_flags; - - /* backing files always opened read-only */ - back_flags = - flags & ~(BDRV_O_RDWR | BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING); - - bs = bdrv_new(""); - - ret = bdrv_open(bs, backing_file->value.s, NULL, back_flags, - backing_drv); - if (ret < 0) { - error_setg_errno(errp, -ret, "Could not open '%s'", - backing_file->value.s); - goto out; - } - bdrv_get_geometry(bs, &size); - size *= 512; - - snprintf(buf, sizeof(buf), "%" PRId64, size); - set_option_parameter(param, BLOCK_OPT_SIZE, buf); - } else { - error_setg(errp, "Image creation needs a size parameter"); - goto out; - } - } - - if (!quiet) { - printf("Formatting '%s', fmt=%s ", filename, fmt); - print_option_parameters(param); - puts(""); - } - ret = bdrv_create(drv, filename, param); - if (ret < 0) { - if (ret == -ENOTSUP) { - error_setg(errp,"Formatting or formatting option not supported for " - "file format '%s'", fmt); - } else if (ret == -EFBIG) { - const char *cluster_size_hint = ""; - if (get_option_parameter(create_options, BLOCK_OPT_CLUSTER_SIZE)) { - cluster_size_hint = " (try using a larger cluster size)"; - } - error_setg(errp, "The image size is too large for file format '%s'%s", - fmt, cluster_size_hint); - } else { - error_setg(errp, "%s: error while creating %s: %s", filename, fmt, - strerror(-ret)); - } - } - -out: - free_option_parameters(create_options); - free_option_parameters(param); - - if (bs) { - bdrv_delete(bs); - } -} - -AioContext *bdrv_get_aio_context(BlockDriverState *bs) -{ - /* Currently BlockDriverState always uses the main loop AioContext */ - return qemu_get_aio_context(); -} - -void bdrv_add_before_write_notifier(BlockDriverState *bs, - NotifierWithReturn *notifier) -{ - notifier_with_return_list_add(&bs->before_write_notifiers, notifier); -} |