gfapi: APIs to store and process upcall notifications received

In case of any upcall cbk events received by the protocol/client,
gfapi will be notified which queues them up in a list (<gfapi_cbk_upcall>).

Applicatons are responsible to provide APIs to process & notify them in case
of any such upcall events queued.

Added a new API which will be used by Ganesha to repeatedly poll for any
such upcall event notified (<glfs_h_poll_upcall>).

A new test-file has been added to test the cache_invalidation upcall events.

Below link has a writeup which explains the code changes done -
        URL: https://soumyakoduri.wordpress.com/2015/02/25/glusterfs-understanding-upcall-infrastructure-and-cache-invalidation-support/

Change-Id: Iafc6880000c865fd4da22d0cfc388ec135b5a1c5
BUG: 1200262
Signed-off-by: Soumya Koduri <skoduri@redhat.com>
Reviewed-on: http://review.gluster.org/9536
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Kaleb KEITHLEY <kkeithle@redhat.com>

1 files changed, 188 insertions, 0 deletions

diff --git a/tests/basic/gfapi/upcall-cache-invalidate.c b/tests/basic/gfapi/upcall-cache-invalidate.c
new file mode 100644
index 00000000000..e91d05d4058
--- /dev/null
+++ b/tests/basic/gfapi/upcall-cache-invalidate.c
@@ -0,0 +1,188 @@
+#include <fcntl.h>
+#include <unistd.h>
+#include <time.h>
+#include <limits.h>
+#include <alloca.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <glusterfs/api/glfs.h>
+#include <glusterfs/api/glfs-handles.h>
+int gfapi = 1;
+
+#define LOG_ERR(func, ret) do { \
+        if (ret != 0) {            \
+                fprintf (stderr, "%s : returned error %d (%s)\n", \
+                         func, ret, strerror (errno)); \
+                goto out; \
+        } else { \
+                fprintf (stderr, "%s : returned %d\n", func, ret); \
+        } \
+        } while (0)
+
+int
+main (int argc, char *argv[])
+{
+        glfs_t    *fs = NULL;
+        glfs_t    *fs2 = NULL;
+        glfs_t    *fs_tmp = NULL;
+        glfs_t    *fs_tmp2 = NULL;
+        int        ret = 0, i;
+        glfs_fd_t *fd = NULL;
+        glfs_fd_t *fd2 = NULL;
+        glfs_fd_t *fd_tmp = NULL;
+        glfs_fd_t *fd_tmp2 = NULL;
+        char       readbuf[32];
+        char      *filename = "file_tmp";
+        char      *writebuf = NULL;
+        char      *vol_id  = NULL;
+        unsigned int       cnt = 1;
+        struct    callback_arg cbk;
+        char      *logfile = NULL;
+        char      *volname = NULL;
+
+        cbk.handle = NULL;
+
+        if (argc != 3) {
+                fprintf (stderr, "Invalid argument\n");
+                exit(1);
+        }
+
+        volname = argv[1];
+        logfile = argv[2];
+
+        fs = glfs_new (volname);
+        if (!fs) {
+                fprintf (stderr, "glfs_new: returned NULL\n");
+                return -1;
+        }
+
+        ret = glfs_set_volfile_server (fs, "tcp", "localhost", 24007);
+        LOG_ERR("glfs_set_volfile_server", ret);
+
+        ret = glfs_set_logging (fs, logfile, 7);
+        LOG_ERR("glfs_set_logging", ret);
+
+        ret = glfs_init (fs);
+        LOG_ERR("glfs_init", ret);
+
+        fs2 = glfs_new (volname);
+        if (!fs2) {
+                fprintf (stderr, "glfs_new fs2: returned NULL\n");
+                return 1;
+        }
+
+        ret = glfs_set_volfile_server (fs2, "tcp", "localhost", 24007);
+        LOG_ERR("glfs_set_volfile_server-fs2", ret);
+
+        ret = glfs_set_logging (fs2, logfile, 7);
+        LOG_ERR("glfs_set_logging-fs2", ret);
+
+        ret = glfs_init (fs2);
+        LOG_ERR("glfs_init-fs2", ret);
+
+        fd = glfs_creat(fs, filename, O_RDWR|O_SYNC, 0644);
+        if (fd <= 0) {
+                ret = -1;
+                LOG_ERR ("glfs_creat", ret);
+        }
+        fprintf (stderr, "glfs-create fd - %d\n", fd);
+
+        fd2 = glfs_open(fs2, filename, O_SYNC|O_RDWR|O_CREAT);
+        if (fd2 <= 0) {
+                ret = -1;
+                LOG_ERR ("glfs_open-fs2", ret);
+        }
+        fprintf (stderr, "glfs-open fd2 - %d\n", fd2);
+
+        do {
+                if (cnt%2) {
+                        fd_tmp = fd;
+                        fs_tmp = fs;
+                        fd_tmp2 = fd2;
+                        fs_tmp2 = fs2;
+                } else {
+                        fd_tmp = fd2;
+                        fs_tmp = fs2;
+                        fd_tmp2 = fd;
+                        fs_tmp2 = fs;
+                }
+
+                /* WRITE on fd_tmp */
+                writebuf = malloc(10);
+                if (writebuf) {
+                        memcpy (writebuf, "abcd", 4);
+                        ret = glfs_write (fd_tmp, writebuf, 4, 0);
+                        if (ret <= 0)   {
+                                ret = -1;
+                                LOG_ERR ("glfs_write", ret);
+                        } else {
+                                fprintf (stderr,
+                                         "glfs_write suceeded\n");
+                        }
+                        free(writebuf);
+                } else {
+                        fprintf (stderr,
+                                 "Could not allocate writebuf\n");
+                        return -1;
+                }
+
+                /* READ on fd_tmp2 */
+                ret = glfs_lseek (fd_tmp2, 0, SEEK_SET);
+                LOG_ERR ("glfs_lseek", ret);
+
+                ret = glfs_pread (fd_tmp2, readbuf, 4, 0, 0);
+
+                if (ret <= 0) {
+                        ret = -1;
+                        LOG_ERR ("glfs_pread", ret);
+                } else {
+                        fprintf (stderr, "glfs_read: %s\n", readbuf);
+                }
+
+                /* Open() fops seem to be not performed on server side until
+                 * there are I/Os on that fd
+                 */
+                if (cnt > 2) {
+                        ret = glfs_h_poll_upcall(fs_tmp, &cbk);
+                        LOG_ERR ("glfs_h_poll_upcall", ret);
+                        if (cbk.handle) {
+                                fprintf (stderr, " upcall event type - %d,"
+                                                 " flags - %d, expire_time_attr - %d\n" ,
+                                         cbk.reason, cbk.flags, cbk.expire_time_attr);
+                        } else {
+                                fprintf (stderr,
+                                         "Dint receive upcall notify event");
+                                ret = -1;
+                                goto err;
+                        }
+                }
+
+                sleep(5);
+        } while (++cnt < 5);
+
+err:
+        glfs_close(fd);
+        LOG_ERR ("glfs_close", ret);
+
+        glfs_close(fd2);
+        LOG_ERR ("glfs_close-fd2", ret);
+
+out:
+        if (fs) {
+                ret = glfs_fini(fs);
+                fprintf (stderr, "glfs_fini(fs) returned %d \n", ret);
+        }
+
+        if (fs2) {
+                ret = glfs_fini(fs2);
+                fprintf (stderr, "glfs_fini(fs2) returned %d \n", ret);
+        }
+
+        if (ret)
+                exit(1);
+        exit(0);
+}
+
+