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authorKaleb S KEITHLEY <kkeithle@redhat.com>2016-02-18 11:21:12 -0500
committerJeff Darcy <jdarcy@redhat.com>2016-03-07 03:34:59 -0800
commit6860968c3adaf2e8c3cb51124bbdfccef74beeb9 (patch)
tree0bb3721f3ae438e7ea7891e0a179cfa63b697a7c /contrib/qemu/block/qcow2-cache.c
parent459d0a5e173f9d9f597aec89f81e5377425eb8fb (diff)
qemu-block: deprecated/defunct, remove from tree
qemu-block xlator is not used by anyone, or so I'm told. It's also substantially out of date. There's little reason to keep it in our sources. (And FedoraProject doesn't like bundled software either.) Change-Id: I4aeb2fdfd962ec6d93de6bae126874121272220a Signed-off-by: Kaleb S KEITHLEY <kkeithle@redhat.com> Reviewed-on: http://review.gluster.org/13473 Smoke: Gluster Build System <jenkins@build.gluster.com> CentOS-regression: Gluster Build System <jenkins@build.gluster.com> NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org> Reviewed-by: Shyamsundar Ranganathan <srangana@redhat.com> Reviewed-by: Jeff Darcy <jdarcy@redhat.com>
Diffstat (limited to 'contrib/qemu/block/qcow2-cache.c')
-rw-r--r--contrib/qemu/block/qcow2-cache.c323
1 files changed, 0 insertions, 323 deletions
diff --git a/contrib/qemu/block/qcow2-cache.c b/contrib/qemu/block/qcow2-cache.c
deleted file mode 100644
index 2f3114ecc24..00000000000
--- a/contrib/qemu/block/qcow2-cache.c
+++ /dev/null
@@ -1,323 +0,0 @@
-/*
- * L2/refcount table cache for the QCOW2 format
- *
- * Copyright (c) 2010 Kevin Wolf <kwolf@redhat.com>
- *
- * 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 "block/block_int.h"
-#include "qemu-common.h"
-#include "qcow2.h"
-#include "trace.h"
-
-typedef struct Qcow2CachedTable {
- void* table;
- int64_t offset;
- bool dirty;
- int cache_hits;
- int ref;
-} Qcow2CachedTable;
-
-struct Qcow2Cache {
- Qcow2CachedTable* entries;
- struct Qcow2Cache* depends;
- int size;
- bool depends_on_flush;
-};
-
-Qcow2Cache *qcow2_cache_create(BlockDriverState *bs, int num_tables)
-{
- BDRVQcowState *s = bs->opaque;
- Qcow2Cache *c;
- int i;
-
- c = g_malloc0(sizeof(*c));
- c->size = num_tables;
- c->entries = g_malloc0(sizeof(*c->entries) * num_tables);
-
- for (i = 0; i < c->size; i++) {
- c->entries[i].table = qemu_blockalign(bs, s->cluster_size);
- }
-
- return c;
-}
-
-int qcow2_cache_destroy(BlockDriverState* bs, Qcow2Cache *c)
-{
- int i;
-
- for (i = 0; i < c->size; i++) {
- assert(c->entries[i].ref == 0);
- qemu_vfree(c->entries[i].table);
- }
-
- g_free(c->entries);
- g_free(c);
-
- return 0;
-}
-
-static int qcow2_cache_flush_dependency(BlockDriverState *bs, Qcow2Cache *c)
-{
- int ret;
-
- ret = qcow2_cache_flush(bs, c->depends);
- if (ret < 0) {
- return ret;
- }
-
- c->depends = NULL;
- c->depends_on_flush = false;
-
- return 0;
-}
-
-static int qcow2_cache_entry_flush(BlockDriverState *bs, Qcow2Cache *c, int i)
-{
- BDRVQcowState *s = bs->opaque;
- int ret = 0;
-
- if (!c->entries[i].dirty || !c->entries[i].offset) {
- return 0;
- }
-
- trace_qcow2_cache_entry_flush(qemu_coroutine_self(),
- c == s->l2_table_cache, i);
-
- if (c->depends) {
- ret = qcow2_cache_flush_dependency(bs, c);
- } else if (c->depends_on_flush) {
- ret = bdrv_flush(bs->file);
- if (ret >= 0) {
- c->depends_on_flush = false;
- }
- }
-
- if (ret < 0) {
- return ret;
- }
-
- if (c == s->refcount_block_cache) {
- BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_UPDATE_PART);
- } else if (c == s->l2_table_cache) {
- BLKDBG_EVENT(bs->file, BLKDBG_L2_UPDATE);
- }
-
- ret = bdrv_pwrite(bs->file, c->entries[i].offset, c->entries[i].table,
- s->cluster_size);
- if (ret < 0) {
- return ret;
- }
-
- c->entries[i].dirty = false;
-
- return 0;
-}
-
-int qcow2_cache_flush(BlockDriverState *bs, Qcow2Cache *c)
-{
- BDRVQcowState *s = bs->opaque;
- int result = 0;
- int ret;
- int i;
-
- trace_qcow2_cache_flush(qemu_coroutine_self(), c == s->l2_table_cache);
-
- for (i = 0; i < c->size; i++) {
- ret = qcow2_cache_entry_flush(bs, c, i);
- if (ret < 0 && result != -ENOSPC) {
- result = ret;
- }
- }
-
- if (result == 0) {
- ret = bdrv_flush(bs->file);
- if (ret < 0) {
- result = ret;
- }
- }
-
- return result;
-}
-
-int qcow2_cache_set_dependency(BlockDriverState *bs, Qcow2Cache *c,
- Qcow2Cache *dependency)
-{
- int ret;
-
- if (dependency->depends) {
- ret = qcow2_cache_flush_dependency(bs, dependency);
- if (ret < 0) {
- return ret;
- }
- }
-
- if (c->depends && (c->depends != dependency)) {
- ret = qcow2_cache_flush_dependency(bs, c);
- if (ret < 0) {
- return ret;
- }
- }
-
- c->depends = dependency;
- return 0;
-}
-
-void qcow2_cache_depends_on_flush(Qcow2Cache *c)
-{
- c->depends_on_flush = true;
-}
-
-static int qcow2_cache_find_entry_to_replace(Qcow2Cache *c)
-{
- int i;
- int min_count = INT_MAX;
- int min_index = -1;
-
-
- for (i = 0; i < c->size; i++) {
- if (c->entries[i].ref) {
- continue;
- }
-
- if (c->entries[i].cache_hits < min_count) {
- min_index = i;
- min_count = c->entries[i].cache_hits;
- }
-
- /* Give newer hits priority */
- /* TODO Check how to optimize the replacement strategy */
- c->entries[i].cache_hits /= 2;
- }
-
- if (min_index == -1) {
- /* This can't happen in current synchronous code, but leave the check
- * here as a reminder for whoever starts using AIO with the cache */
- abort();
- }
- return min_index;
-}
-
-static int qcow2_cache_do_get(BlockDriverState *bs, Qcow2Cache *c,
- uint64_t offset, void **table, bool read_from_disk)
-{
- BDRVQcowState *s = bs->opaque;
- int i;
- int ret;
-
- trace_qcow2_cache_get(qemu_coroutine_self(), c == s->l2_table_cache,
- offset, read_from_disk);
-
- /* Check if the table is already cached */
- for (i = 0; i < c->size; i++) {
- if (c->entries[i].offset == offset) {
- goto found;
- }
- }
-
- /* If not, write a table back and replace it */
- i = qcow2_cache_find_entry_to_replace(c);
- trace_qcow2_cache_get_replace_entry(qemu_coroutine_self(),
- c == s->l2_table_cache, i);
- if (i < 0) {
- return i;
- }
-
- ret = qcow2_cache_entry_flush(bs, c, i);
- if (ret < 0) {
- return ret;
- }
-
- trace_qcow2_cache_get_read(qemu_coroutine_self(),
- c == s->l2_table_cache, i);
- c->entries[i].offset = 0;
- if (read_from_disk) {
- if (c == s->l2_table_cache) {
- BLKDBG_EVENT(bs->file, BLKDBG_L2_LOAD);
- }
-
- ret = bdrv_pread(bs->file, offset, c->entries[i].table, s->cluster_size);
- if (ret < 0) {
- return ret;
- }
- }
-
- /* Give the table some hits for the start so that it won't be replaced
- * immediately. The number 32 is completely arbitrary. */
- c->entries[i].cache_hits = 32;
- c->entries[i].offset = offset;
-
- /* And return the right table */
-found:
- c->entries[i].cache_hits++;
- c->entries[i].ref++;
- *table = c->entries[i].table;
-
- trace_qcow2_cache_get_done(qemu_coroutine_self(),
- c == s->l2_table_cache, i);
-
- return 0;
-}
-
-int qcow2_cache_get(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
- void **table)
-{
- return qcow2_cache_do_get(bs, c, offset, table, true);
-}
-
-int qcow2_cache_get_empty(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
- void **table)
-{
- return qcow2_cache_do_get(bs, c, offset, table, false);
-}
-
-int qcow2_cache_put(BlockDriverState *bs, Qcow2Cache *c, void **table)
-{
- int i;
-
- for (i = 0; i < c->size; i++) {
- if (c->entries[i].table == *table) {
- goto found;
- }
- }
- return -ENOENT;
-
-found:
- c->entries[i].ref--;
- *table = NULL;
-
- assert(c->entries[i].ref >= 0);
- return 0;
-}
-
-void qcow2_cache_entry_mark_dirty(Qcow2Cache *c, void *table)
-{
- int i;
-
- for (i = 0; i < c->size; i++) {
- if (c->entries[i].table == table) {
- goto found;
- }
- }
- abort();
-
-found:
- c->entries[i].dirty = true;
-}