diff --git a/block/gluster.c b/block/gluster.c index d9aace6253..a8aaacf645 100644 --- a/block/gluster.c +++ b/block/gluster.c @@ -314,6 +314,23 @@ static int qemu_gluster_open(BlockDriverState *bs, QDict *options, goto out; } +#ifdef CONFIG_GLUSTERFS_XLATOR_OPT + /* Without this, if fsync fails for a recoverable reason (for instance, + * ENOSPC), gluster will dump its cache, preventing retries. This means + * almost certain data loss. Not all gluster versions support the + * 'resync-failed-syncs-after-fsync' key value, but there is no way to + * discover during runtime if it is supported (this api returns success for + * unknown key/value pairs) */ + ret = glfs_set_xlator_option(s->glfs, "*-write-behind", + "resync-failed-syncs-after-fsync", + "on"); + if (ret < 0) { + error_setg_errno(errp, errno, "Unable to set xlator key/value pair"); + ret = -errno; + goto out; + } +#endif + qemu_gluster_parse_flags(bdrv_flags, &open_flags); s->fd = glfs_open(s->glfs, gconf->image, open_flags); @@ -366,6 +383,16 @@ static int qemu_gluster_reopen_prepare(BDRVReopenState *state, goto exit; } +#ifdef CONFIG_GLUSTERFS_XLATOR_OPT + ret = glfs_set_xlator_option(reop_s->glfs, "*-write-behind", + "resync-failed-syncs-after-fsync", "on"); + if (ret < 0) { + error_setg_errno(errp, errno, "Unable to set xlator key/value pair"); + ret = -errno; + goto exit; + } +#endif + reop_s->fd = glfs_open(reop_s->glfs, gconf->image, open_flags); if (reop_s->fd == NULL) { /* reops->glfs will be cleaned up in _abort */ @@ -613,11 +640,35 @@ static coroutine_fn int qemu_gluster_co_flush_to_disk(BlockDriverState *bs) ret = glfs_fsync_async(s->fd, gluster_finish_aiocb, &acb); if (ret < 0) { - return -errno; + ret = -errno; + goto error; } qemu_coroutine_yield(); + if (acb.ret < 0) { + ret = acb.ret; + goto error; + } + return acb.ret; + +error: + /* Some versions of Gluster (3.5.6 -> 3.5.8?) will not retain its cache + * after a fsync failure, so we have no way of allowing the guest to safely + * continue. Gluster versions prior to 3.5.6 don't retain the cache + * either, but will invalidate the fd on error, so this is again our only + * option. + * + * The 'resync-failed-syncs-after-fsync' xlator option for the + * write-behind cache will cause later gluster versions to retain its + * cache after error, so long as the fd remains open. However, we + * currently have no way of knowing if this option is supported. + * + * TODO: Once gluster provides a way for us to determine if the option + * is supported, bypass the closure and setting drv to NULL. */ + qemu_gluster_close(bs); + bs->drv = NULL; + return ret; } #ifdef CONFIG_GLUSTERFS_DISCARD diff --git a/configure b/configure index f1c307bfc6..ab54f3c8ee 100755 --- a/configure +++ b/configure @@ -298,6 +298,7 @@ coroutine="" coroutine_pool="" seccomp="" glusterfs="" +glusterfs_xlator_opt="no" glusterfs_discard="no" glusterfs_zerofill="no" archipelago="no" @@ -3400,6 +3401,9 @@ if test "$glusterfs" != "no" ; then glusterfs="yes" glusterfs_cflags=`$pkg_config --cflags glusterfs-api` glusterfs_libs=`$pkg_config --libs glusterfs-api` + if $pkg_config --atleast-version=4 glusterfs-api; then + glusterfs_xlator_opt="yes" + fi if $pkg_config --atleast-version=5 glusterfs-api; then glusterfs_discard="yes" fi @@ -5342,6 +5346,10 @@ if test "$glusterfs" = "yes" ; then echo "GLUSTERFS_LIBS=$glusterfs_libs" >> $config_host_mak fi +if test "$glusterfs_xlator_opt" = "yes" ; then + echo "CONFIG_GLUSTERFS_XLATOR_OPT=y" >> $config_host_mak +fi + if test "$glusterfs_discard" = "yes" ; then echo "CONFIG_GLUSTERFS_DISCARD=y" >> $config_host_mak fi