commit ae9f3bd8259a0a8f67be2420e66bb05fbb95af48 upstream.
Currently, sdp->sd_aspace and the per-inode metadata address spaces use sb->s_bdev->bd_mapping->host as their ->host; folios in those address spaces will thus appear to be on bdev rather than on gfs2 filesystems. This is a problem because gfs2 doesn't support cgroup writeback (SB_I_CGROUPWB), but bdev does.
Fix that by using a "dummy" gfs2 inode as ->host in those address spaces. When coming from a folio, folio->mapping->host->i_sb will then be a gfs2 super block and the SB_I_CGROUPWB flag will not be set in sb->s_iflags.
Based on a previous version from Bob Peterson from several years ago. Thanks to Tetsuo Handa, Jan Kara, and Rafael Aquini for helping figure this out.
Fixes: aaa2cacf8184 ("writeback: add lockdep annotation to inode_to_wb()") Signed-off-by: Andreas Gruenbacher agruenba@redhat.com Signed-off-by: Sumanth Gavini sumanth.gavini@yahoo.com --- fs/gfs2/glock.c | 3 +-- fs/gfs2/glops.c | 4 ++-- fs/gfs2/incore.h | 9 ++++++++- fs/gfs2/meta_io.c | 2 +- fs/gfs2/meta_io.h | 4 +--- fs/gfs2/ops_fstype.c | 28 ++++++++++++++++------------ fs/gfs2/super.c | 2 +- 7 files changed, 30 insertions(+), 22 deletions(-)
diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c index 4a280be229a6..7ab1b4dac0bb 100644 --- a/fs/gfs2/glock.c +++ b/fs/gfs2/glock.c @@ -1146,7 +1146,6 @@ int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number, const struct gfs2_glock_operations *glops, int create, struct gfs2_glock **glp) { - struct super_block *s = sdp->sd_vfs; struct lm_lockname name = { .ln_number = number, .ln_type = glops->go_type, .ln_sbd = sdp }; @@ -1210,7 +1209,7 @@ int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number, mapping = gfs2_glock2aspace(gl); if (mapping) { mapping->a_ops = &gfs2_meta_aops; - mapping->host = s->s_bdev->bd_inode; + mapping->host = sdp->sd_inode; mapping->flags = 0; mapping_set_gfp_mask(mapping, GFP_NOFS); mapping->private_data = NULL; diff --git a/fs/gfs2/glops.c b/fs/gfs2/glops.c index f41ca89d216b..5877afdb11c5 100644 --- a/fs/gfs2/glops.c +++ b/fs/gfs2/glops.c @@ -165,7 +165,7 @@ void gfs2_ail_flush(struct gfs2_glock *gl, bool fsync) static int gfs2_rgrp_metasync(struct gfs2_glock *gl) { struct gfs2_sbd *sdp = gl->gl_name.ln_sbd; - struct address_space *metamapping = &sdp->sd_aspace; + struct address_space *metamapping = gfs2_aspace(sdp); struct gfs2_rgrpd *rgd = gfs2_glock2rgrp(gl); const unsigned bsize = sdp->sd_sb.sb_bsize; loff_t start = (rgd->rd_addr * bsize) & PAGE_MASK; @@ -222,7 +222,7 @@ static int rgrp_go_sync(struct gfs2_glock *gl) static void rgrp_go_inval(struct gfs2_glock *gl, int flags) { struct gfs2_sbd *sdp = gl->gl_name.ln_sbd; - struct address_space *mapping = &sdp->sd_aspace; + struct address_space *mapping = gfs2_aspace(sdp); struct gfs2_rgrpd *rgd = gfs2_glock2rgrp(gl); const unsigned bsize = sdp->sd_sb.sb_bsize; loff_t start, end; diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h index a8c95c5293c6..52712ec33d91 100644 --- a/fs/gfs2/incore.h +++ b/fs/gfs2/incore.h @@ -795,7 +795,7 @@ struct gfs2_sbd {
/* Log stuff */
- struct address_space sd_aspace; + struct inode *sd_inode;
spinlock_t sd_log_lock;
@@ -850,6 +850,13 @@ struct gfs2_sbd { unsigned long sd_glock_dqs_held; };
+#define GFS2_BAD_INO 1 + +static inline struct address_space *gfs2_aspace(struct gfs2_sbd *sdp) +{ + return sdp->sd_inode->i_mapping; +} + static inline void gfs2_glstats_inc(struct gfs2_glock *gl, int which) { gl->gl_stats.stats[which]++; diff --git a/fs/gfs2/meta_io.c b/fs/gfs2/meta_io.c index 924361fa510b..fca8ea2f4504 100644 --- a/fs/gfs2/meta_io.c +++ b/fs/gfs2/meta_io.c @@ -122,7 +122,7 @@ struct buffer_head *gfs2_getbuf(struct gfs2_glock *gl, u64 blkno, int create) unsigned int bufnum;
if (mapping == NULL) - mapping = &sdp->sd_aspace; + mapping = gfs2_aspace(sdp);
shift = PAGE_SHIFT - sdp->sd_sb.sb_bsize_shift; index = blkno >> shift; /* convert block to page */ diff --git a/fs/gfs2/meta_io.h b/fs/gfs2/meta_io.h index d0a58cdd433a..a4c3865137d4 100644 --- a/fs/gfs2/meta_io.h +++ b/fs/gfs2/meta_io.h @@ -44,9 +44,7 @@ static inline struct gfs2_sbd *gfs2_mapping2sbd(struct address_space *mapping) struct gfs2_glock_aspace *gla = container_of(mapping, struct gfs2_glock_aspace, mapping); return gla->glock.gl_name.ln_sbd; - } else if (mapping->a_ops == &gfs2_rgrp_aops) - return container_of(mapping, struct gfs2_sbd, sd_aspace); - else + } else return inode->i_sb->s_fs_info; }
diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c index 33ca04733e93..9933c7328dcb 100644 --- a/fs/gfs2/ops_fstype.c +++ b/fs/gfs2/ops_fstype.c @@ -72,7 +72,6 @@ void free_sbd(struct gfs2_sbd *sdp) static struct gfs2_sbd *init_sbd(struct super_block *sb) { struct gfs2_sbd *sdp; - struct address_space *mapping;
sdp = kzalloc(sizeof(struct gfs2_sbd), GFP_KERNEL); if (!sdp) @@ -110,16 +109,6 @@ static struct gfs2_sbd *init_sbd(struct super_block *sb)
INIT_LIST_HEAD(&sdp->sd_sc_inodes_list);
- mapping = &sdp->sd_aspace; - - address_space_init_once(mapping); - mapping->a_ops = &gfs2_rgrp_aops; - mapping->host = sb->s_bdev->bd_inode; - mapping->flags = 0; - mapping_set_gfp_mask(mapping, GFP_NOFS); - mapping->private_data = NULL; - mapping->writeback_index = 0; - spin_lock_init(&sdp->sd_log_lock); atomic_set(&sdp->sd_log_pinned, 0); INIT_LIST_HEAD(&sdp->sd_log_revokes); @@ -1159,6 +1148,7 @@ static int gfs2_fill_super(struct super_block *sb, struct fs_context *fc) int silent = fc->sb_flags & SB_SILENT; struct gfs2_sbd *sdp; struct gfs2_holder mount_gh; + struct address_space *mapping; int error;
sdp = init_sbd(sb); @@ -1206,9 +1196,21 @@ static int gfs2_fill_super(struct super_block *sb, struct fs_context *fc) sdp->sd_tune.gt_statfs_quantum = 30; }
+ /* Set up an address space for metadata writes */ + sdp->sd_inode = new_inode(sb); + error = -ENOMEM; + if (!sdp->sd_inode) + goto fail_free; + sdp->sd_inode->i_ino = GFS2_BAD_INO; + sdp->sd_inode->i_size = OFFSET_MAX; + + mapping = gfs2_aspace(sdp); + mapping->a_ops = &gfs2_rgrp_aops; + mapping_set_gfp_mask(mapping, GFP_NOFS); + error = init_names(sdp, silent); if (error) - goto fail_free; + goto fail_iput;
snprintf(sdp->sd_fsname, sizeof(sdp->sd_fsname), "%s", sdp->sd_table_name);
@@ -1327,6 +1329,8 @@ static int gfs2_fill_super(struct super_block *sb, struct fs_context *fc) gfs2_sys_fs_del(sdp); fail_delete_wq: destroy_workqueue(sdp->sd_delete_wq); +fail_iput: + iput(sdp->sd_inode); fail_free: free_sbd(sdp); sb->s_fs_info = NULL; diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c index 02d93da21b2b..47e0b5c96d1c 100644 --- a/fs/gfs2/super.c +++ b/fs/gfs2/super.c @@ -642,7 +642,7 @@ static void gfs2_put_super(struct super_block *sb) gfs2_jindex_free(sdp); /* Take apart glock structures and buffer lists */ gfs2_gl_hash_clear(sdp); - truncate_inode_pages_final(&sdp->sd_aspace); + iput(sdp->sd_inode); gfs2_delete_debugfs_file(sdp); /* Unmount the locking protocol */ gfs2_lm_unmount(sdp);
[ Sasha's backport helper bot ]
Hi,
Summary of potential issues: ❌ Patch application failures detected ⚠️ Found follow-up fixes in mainline
The upstream commit SHA1 provided is correct: ae9f3bd8259a0a8f67be2420e66bb05fbb95af48
WARNING: Author mismatch between patch and upstream commit: Backport author: Sumanth Gavini sumanth.gavini@yahoo.com Commit author: Andreas Gruenbacher agruenba@redhat.com
Status in newer kernel trees: 6.15.y | Present (different SHA1: 67c02d33ab1a) 6.12.y | Present (different SHA1: 271e6bf41afa)
Found fixes commits: 9126d2754c5e gfs2: Don't clear sb->s_fs_info in gfs2_sys_fs_add
Note: Could not generate a diff with upstream commit: --- Note: Could not generate diff - patch failed to apply for comparison ---
Results of testing on various branches:
| Branch | Patch Apply | Build Test | |---------------------------|-------------|------------| | origin/linux-6.6.y | Failed | N/A |
On Tue, Aug 05, 2025 at 02:40:04PM -0500, Sumanth Gavini wrote:
commit ae9f3bd8259a0a8f67be2420e66bb05fbb95af48 upstream.
Currently, sdp->sd_aspace and the per-inode metadata address spaces use sb->s_bdev->bd_mapping->host as their ->host; folios in those address spaces will thus appear to be on bdev rather than on gfs2 filesystems. This is a problem because gfs2 doesn't support cgroup writeback (SB_I_CGROUPWB), but bdev does.
Fix that by using a "dummy" gfs2 inode as ->host in those address spaces. When coming from a folio, folio->mapping->host->i_sb will then be a gfs2 super block and the SB_I_CGROUPWB flag will not be set in sb->s_iflags.
Based on a previous version from Bob Peterson from several years ago. Thanks to Tetsuo Handa, Jan Kara, and Rafael Aquini for helping figure this out.
Fixes: aaa2cacf8184 ("writeback: add lockdep annotation to inode_to_wb()") Signed-off-by: Andreas Gruenbacher agruenba@redhat.com Signed-off-by: Sumanth Gavini sumanth.gavini@yahoo.com
This is very different from the original commit and you did not document that :(
Please fix up and resend.
thanks,
greg k-h
linux-stable-mirror@lists.linaro.org