From 9b41d9c1b2be8dc3ea9709a553ffd822f1a66720 Mon Sep 17 00:00:00 2001 From: Chunwei Chen Date: Mon, 7 Dec 2015 15:43:53 -0800 Subject: [PATCH] Use spa as key besides objsetid for snapentry objsetid is not unique across pool, so using it solely as key would cause panic when automounting two snapshot on different pools with the same objsetid. We fix this by adding spa pointer as additional key. Signed-off-by: Chunwei Chen Signed-off-by: Brian Behlendorf Signed-off-by: Richard Yao Issue #3948 Issue #3786 Issue #3887 --- include/sys/zfs_ctldir.h | 3 ++- module/zfs/zfs_ctldir.c | 32 ++++++++++++++++++++++---------- module/zfs/zpl_inode.c | 3 ++- 3 files changed, 26 insertions(+), 12 deletions(-) diff --git a/include/sys/zfs_ctldir.h b/include/sys/zfs_ctldir.h index 960a9a6291..65c44f3cca 100644 --- a/include/sys/zfs_ctldir.h +++ b/include/sys/zfs_ctldir.h @@ -77,7 +77,8 @@ extern int zfsctl_snapdir_mkdir(struct inode *dip, char *dirname, vattr_t *vap, extern void zfsctl_snapdir_inactive(struct inode *ip); extern int zfsctl_snapshot_mount(struct path *path, int flags); extern int zfsctl_snapshot_unmount(char *snapname, int flags); -extern int zfsctl_snapshot_unmount_delay(uint64_t objsetid, int delay); +extern int zfsctl_snapshot_unmount_delay(spa_t *spa, uint64_t objsetid, + int delay); extern int zfsctl_lookup_objset(struct super_block *sb, uint64_t objsetid, zfs_sb_t **zsb); diff --git a/module/zfs/zfs_ctldir.c b/module/zfs/zfs_ctldir.c index bb3686df1f..a00d61d1a6 100644 --- a/module/zfs/zfs_ctldir.c +++ b/module/zfs/zfs_ctldir.c @@ -81,6 +81,7 @@ #include #include #include +#include #include #include #include @@ -117,6 +118,7 @@ static taskq_t *zfs_expire_taskq; typedef struct { char *se_name; /* full snapshot name */ char *se_path; /* full mount path */ + spa_t *se_spa; /* pool spa */ uint64_t se_objsetid; /* snapshot objset id */ struct dentry *se_root_dentry; /* snapshot root dentry */ taskqid_t se_taskqid; /* scheduled unmount taskqid */ @@ -132,8 +134,8 @@ static void zfsctl_snapshot_unmount_delay_impl(zfs_snapentry_t *se, int delay); * the snapshot name and provided mount point. No reference is taken. */ static zfs_snapentry_t * -zfsctl_snapshot_alloc(char *full_name, char *full_path, uint64_t objsetid, - struct dentry *root_dentry) +zfsctl_snapshot_alloc(char *full_name, char *full_path, spa_t *spa, + uint64_t objsetid, struct dentry *root_dentry) { zfs_snapentry_t *se; @@ -141,6 +143,7 @@ zfsctl_snapshot_alloc(char *full_name, char *full_path, uint64_t objsetid, se->se_name = strdup(full_name); se->se_path = strdup(full_path); + se->se_spa = spa; se->se_objsetid = objsetid; se->se_root_dentry = root_dentry; se->se_taskqid = -1; @@ -242,6 +245,9 @@ snapentry_compare_by_objsetid(const void *a, const void *b) const zfs_snapentry_t *se_a = a; const zfs_snapentry_t *se_b = b; + if (se_a->se_spa != se_b->se_spa) + return ((ulong_t)se_a->se_spa < (ulong_t)se_b->se_spa ? -1 : 1); + if (se_a->se_objsetid < se_b->se_objsetid) return (-1); else if (se_a->se_objsetid > se_b->se_objsetid) @@ -278,12 +284,13 @@ zfsctl_snapshot_find_by_name(char *snapname) * as zfsctl_snapshot_find_by_name(). */ static zfs_snapentry_t * -zfsctl_snapshot_find_by_objsetid(uint64_t objsetid) +zfsctl_snapshot_find_by_objsetid(spa_t *spa, uint64_t objsetid) { zfs_snapentry_t *se, search; ASSERT(MUTEX_HELD(&zfs_snapshot_lock)); + search.se_spa = spa; search.se_objsetid = objsetid; se = avl_find(&zfs_snapshots_by_objsetid, &search, NULL); if (se) @@ -323,6 +330,7 @@ static void snapentry_expire(void *data) { zfs_snapentry_t *se = (zfs_snapentry_t *)data; + spa_t *spa = se->se_spa; uint64_t objsetid = se->se_objsetid; if (zfs_expire_snapshot <= 0) { @@ -339,7 +347,7 @@ snapentry_expire(void *data) * This can occur when the snapshot is busy. */ mutex_enter(&zfs_snapshot_lock); - if ((se = zfsctl_snapshot_find_by_objsetid(objsetid)) != NULL) { + if ((se = zfsctl_snapshot_find_by_objsetid(spa, objsetid)) != NULL) { zfsctl_snapshot_unmount_delay_impl(se, zfs_expire_snapshot); zfsctl_snapshot_rele(se); } @@ -385,13 +393,13 @@ zfsctl_snapshot_unmount_delay_impl(zfs_snapentry_t *se, int delay) * and held until the outstanding task is handled or cancelled. */ int -zfsctl_snapshot_unmount_delay(uint64_t objsetid, int delay) +zfsctl_snapshot_unmount_delay(spa_t *spa, uint64_t objsetid, int delay) { zfs_snapentry_t *se; int error = ENOENT; mutex_enter(&zfs_snapshot_lock); - if ((se = zfsctl_snapshot_find_by_objsetid(objsetid)) != NULL) { + if ((se = zfsctl_snapshot_find_by_objsetid(spa, objsetid)) != NULL) { zfsctl_snapshot_unmount_cancel(se); zfsctl_snapshot_unmount_delay_impl(se, delay); zfsctl_snapshot_rele(se); @@ -568,10 +576,12 @@ zfsctl_destroy(zfs_sb_t *zsb) { if (zsb->z_issnap) { zfs_snapentry_t *se; + spa_t *spa = zsb->z_os->os_spa; uint64_t objsetid = dmu_objset_id(zsb->z_os); mutex_enter(&zfs_snapshot_lock); - if ((se = zfsctl_snapshot_find_by_objsetid(objsetid)) != NULL) { + if ((se = zfsctl_snapshot_find_by_objsetid(spa, objsetid)) + != NULL) { zfsctl_snapshot_unmount_cancel(se); zfsctl_snapshot_remove(se); zfsctl_snapshot_rele(se); @@ -1137,7 +1147,8 @@ zfsctl_snapshot_mount(struct path *path, int flags) mutex_enter(&zfs_snapshot_lock); se = zfsctl_snapshot_alloc(full_name, full_path, - dmu_objset_id(snap_zsb->z_os), dentry); + snap_zsb->z_os->os_spa, dmu_objset_id(snap_zsb->z_os), + dentry); zfsctl_snapshot_add(se); zfsctl_snapshot_unmount_delay_impl(se, zfs_expire_snapshot); mutex_exit(&zfs_snapshot_lock); @@ -1160,6 +1171,7 @@ zfsctl_lookup_objset(struct super_block *sb, uint64_t objsetid, zfs_sb_t **zsbp) { zfs_snapentry_t *se; int error; + spa_t *spa = ((zfs_sb_t *)(sb->s_fs_info))->z_os->os_spa; /* * Verify that the snapshot is mounted then lookup the mounted root @@ -1169,7 +1181,7 @@ zfsctl_lookup_objset(struct super_block *sb, uint64_t objsetid, zfs_sb_t **zsbp) * because we hold the zfs_snapshot_lock to prevent the race. */ mutex_enter(&zfs_snapshot_lock); - if ((se = zfsctl_snapshot_find_by_objsetid(objsetid)) != NULL) { + if ((se = zfsctl_snapshot_find_by_objsetid(spa, objsetid)) != NULL) { zfs_sb_t *zsb; zsb = ITOZSB(se->se_root_dentry->d_inode); @@ -1178,7 +1190,7 @@ zfsctl_lookup_objset(struct super_block *sb, uint64_t objsetid, zfs_sb_t **zsbp) if (time_after(jiffies, zsb->z_snap_defer_time + MAX(zfs_expire_snapshot * HZ / 2, HZ))) { zsb->z_snap_defer_time = jiffies; - zfsctl_snapshot_unmount_delay(objsetid, + zfsctl_snapshot_unmount_delay(spa, objsetid, zfs_expire_snapshot); } diff --git a/module/zfs/zpl_inode.c b/module/zfs/zpl_inode.c index 6475c72d71..e0e8ee3ac5 100644 --- a/module/zfs/zpl_inode.c +++ b/module/zfs/zpl_inode.c @@ -28,6 +28,7 @@ #include #include #include +#include #include #include @@ -500,7 +501,7 @@ zpl_revalidate(struct dentry *dentry, unsigned int flags) if (time_after(jiffies, zsb->z_snap_defer_time + MAX(zfs_expire_snapshot * HZ / 2, HZ))) { zsb->z_snap_defer_time = jiffies; - zfsctl_snapshot_unmount_delay( + zfsctl_snapshot_unmount_delay(zsb->z_os->os_spa, dmu_objset_id(zsb->z_os), zfs_expire_snapshot); } }