| Message ID | 20250407182104.716631-2-agruenba@redhat.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Fix false warning in inode_to_wb | expand |
On 2025/04/08 3:21, Andreas Gruenbacher wrote: > @@ -1156,6 +1146,18 @@ static int gfs2_fill_super(struct super_block *sb, struct fs_context *fc) > sb->s_flags |= SB_NOSEC; > sb->s_magic = GFS2_MAGIC; > sb->s_op = &gfs2_super_ops; > + > + /* Set up an address space for metadata writes */ > + sdp->sd_inode = new_inode(sb); > + 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); > + > sb->s_d_op = &gfs2_dops; > sb->s_export_op = &gfs2_export_ops; > sb->s_qcop = &gfs2_quotactl_ops; This will be an inode leak when hitting e.g. error = init_names(sdp, silent); if (error) goto fail_free; path, for what free_sbd() in fail_free: free_sbd(sdp); sb->s_fs_info = NULL; return error; path does is nothing but free_percpu() and kfree().
On Tue, Apr 8, 2025 at 8:04 AM Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> wrote: > On 2025/04/08 3:21, Andreas Gruenbacher wrote: > > @@ -1156,6 +1146,18 @@ static int gfs2_fill_super(struct super_block *sb, struct fs_context *fc) > > sb->s_flags |= SB_NOSEC; > > sb->s_magic = GFS2_MAGIC; > > sb->s_op = &gfs2_super_ops; > > + > > + /* Set up an address space for metadata writes */ > > + sdp->sd_inode = new_inode(sb); > > + 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); > > + > > sb->s_d_op = &gfs2_dops; > > sb->s_export_op = &gfs2_export_ops; > > sb->s_qcop = &gfs2_quotactl_ops; > > This will be an inode leak when hitting e.g. > > error = init_names(sdp, silent); > if (error) > goto fail_free; > > path, for what free_sbd() in > > fail_free: > free_sbd(sdp); > sb->s_fs_info = NULL; > return error; > > path does is nothing but free_percpu() and kfree(). Indeed, an iput() is indeed needed in that case. Thanks, Andreas
On Mon, Apr 07, 2025 at 08:21:01PM +0200, Andreas Gruenbacher wrote: > Use a dummy inode as mapping->host of the address spaces for global as > well as per-inode metadata. The global metadata address space is now > accessed as gfs2_aspace(sdp) instead of sdp->sd_aspace. The per-inode > metadata address spaces are still accessed as > gfs2_glock2aspace(GFS2_I(inode)->i_gl). > > Based on a previous version from Bob Peterson from several years ago. Please explain why you are doing this, not just what.
On Thu, Apr 10, 2025 at 11:01 AM Christoph Hellwig <hch@infradead.org> wrote: > On Mon, Apr 07, 2025 at 08:21:01PM +0200, Andreas Gruenbacher wrote: > > Use a dummy inode as mapping->host of the address spaces for global as > > well as per-inode metadata. The global metadata address space is now > > accessed as gfs2_aspace(sdp) instead of sdp->sd_aspace. The per-inode > > metadata address spaces are still accessed as > > gfs2_glock2aspace(GFS2_I(inode)->i_gl). > > > > Based on a previous version from Bob Peterson from several years ago. > > Please explain why you are doing this, not just what. Right, I have this description now: 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. Those "bdev" filesystems will have the SB_I_CGROUPWB flag set to indicate cgroup writeback support. In fact, gfs2 doesn't support cgroup writeback, though. To fix that, use a "dummy" gfs2 inode as ->host of those address spaces instead. This will then allow functions like inode_to_wb() to determine that the folio belongs to a a filesystem without cgroup writeback support. Thanks, Andreas
diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c index d7220a6fe8f5..ba25b884169e 100644 --- a/fs/gfs2/glock.c +++ b/fs/gfs2/glock.c @@ -1166,7 +1166,6 @@ 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 }; @@ -1229,7 +1228,7 @@ 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_mapping->host; + mapping->host = sdp->sd_inode; mapping->flags = 0; mapping_set_gfp_mask(mapping, GFP_NOFS); mapping->i_private_data = NULL; diff --git a/fs/gfs2/glops.c b/fs/gfs2/glops.c index eb4714f299ef..116efe335c32 100644 --- a/fs/gfs2/glops.c +++ b/fs/gfs2/glops.c @@ -168,7 +168,7 @@ 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; @@ -225,7 +225,7 @@ 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 74abbd4970f8..0a41c4e76b32 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; @@ -851,6 +851,13 @@ 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 198cc7056637..9dc8885c95d0 100644 --- a/fs/gfs2/meta_io.c +++ b/fs/gfs2/meta_io.c @@ -132,7 +132,7 @@ 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 831d988c2ceb..b7c8a6684d02 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 e83d293c3614..ce6ee494ffc4 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) @@ -109,16 +108,6 @@ 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_mapping->host; - mapping->flags = 0; - mapping_set_gfp_mask(mapping, GFP_NOFS); - mapping->i_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); @@ -1135,6 +1124,7 @@ 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); @@ -1156,6 +1146,18 @@ static int gfs2_fill_super(struct super_block *sb, struct fs_context *fc) sb->s_flags |= SB_NOSEC; sb->s_magic = GFS2_MAGIC; sb->s_op = &gfs2_super_ops; + + /* Set up an address space for metadata writes */ + sdp->sd_inode = new_inode(sb); + 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); + sb->s_d_op = &gfs2_dops; sb->s_export_op = &gfs2_export_ops; sb->s_qcop = &gfs2_quotactl_ops; diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c index 44e5658b896c..4529b7dda8ca 100644 --- a/fs/gfs2/super.c +++ b/fs/gfs2/super.c @@ -648,7 +648,7 @@ 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); gfs2_sys_fs_del(sdp);
Use a dummy inode as mapping->host of the address spaces for global as well as per-inode metadata. The global metadata address space is now accessed as gfs2_aspace(sdp) instead of sdp->sd_aspace. The per-inode metadata address spaces are still accessed as gfs2_glock2aspace(GFS2_I(inode)->i_gl). Based on a previous version from Bob Peterson from several years ago. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.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 | 24 +++++++++++++----------- fs/gfs2/super.c | 2 +- 7 files changed, 27 insertions(+), 21 deletions(-)