Currently every ext4 inode gets mapping_metadata_bhs struct although it is only needed when running without a journal and only for inodes where any metadata was dirtied. Allocate mapping_metadata_bhs struct on demand when dirtying the first metadata buffer for the inode. Acked-by: Theodore Ts'o Signed-off-by: Jan Kara --- fs/ext4/ext4.h | 13 ++++++++++++- fs/ext4/ext4_jbd2.c | 25 +++++++++++++++++++++---- fs/ext4/fsync.c | 12 ++++++++---- fs/ext4/inode.c | 12 ++++++++---- fs/ext4/super.c | 9 ++++++--- 5 files changed, 55 insertions(+), 16 deletions(-) diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index b37c136ea3ab..64f8f63f4415 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1151,7 +1151,7 @@ struct ext4_inode_info { struct rw_semaphore i_data_sem; struct inode vfs_inode; struct jbd2_inode *jinode; - struct mapping_metadata_bhs i_metadata_bhs; + struct mapping_metadata_bhs *i_metadata_bhs; /* * File creation time. Its function is same as that of @@ -2126,6 +2126,17 @@ static inline bool ext4_inode_orphan_tracked(struct inode *inode) !list_empty(&EXT4_I(inode)->i_orphan); } +static inline struct mapping_metadata_bhs *ext4_i_metadata_bhs( + struct inode *inode) +{ + /* + * i_metadata_bhs is set in ext4_inode_attach_mmb() using cmpxchg(). + * We use READ_ONCE when accessing i_metadata_bhs to make sure we get + * consistent view for all accesses. + */ + return READ_ONCE(EXT4_I(inode)->i_metadata_bhs); +} + /* * Codes for operating systems */ diff --git a/fs/ext4/ext4_jbd2.c b/fs/ext4/ext4_jbd2.c index 9a8c225f2753..3b2f8ac20bf8 100644 --- a/fs/ext4/ext4_jbd2.c +++ b/fs/ext4/ext4_jbd2.c @@ -350,6 +350,21 @@ int __ext4_journal_get_create_access(const char *where, unsigned int line, return 0; } +static void ext4_inode_attach_mmb(struct inode *inode) +{ + struct mapping_metadata_bhs *mmb; + + /* + * It's difficult to handle failure when marking buffer dirty without + * leaving filesystem corrupted + */ + mmb = kmalloc_obj(*mmb, GFP_NOFS | __GFP_NOFAIL); + mmb_init(mmb, &inode->i_data); + /* Someone swapped another mmb before us? */ + if (cmpxchg(&EXT4_I(inode)->i_metadata_bhs, NULL, mmb)) + kfree(mmb); +} + int __ext4_handle_dirty_metadata(const char *where, unsigned int line, handle_t *handle, struct inode *inode, struct buffer_head *bh) @@ -389,11 +404,13 @@ int __ext4_handle_dirty_metadata(const char *where, unsigned int line, err); } } else { - if (inode) - mmb_mark_buffer_dirty(bh, - &EXT4_I(inode)->i_metadata_bhs); - else + if (inode) { + if (!ext4_i_metadata_bhs(inode)) + ext4_inode_attach_mmb(inode); + mmb_mark_buffer_dirty(bh, ext4_i_metadata_bhs(inode)); + } else { mark_buffer_dirty(bh); + } if (inode && inode_needs_sync(inode)) { sync_dirty_buffer(bh); if (buffer_req(bh) && !buffer_uptodate(bh)) { diff --git a/fs/ext4/fsync.c b/fs/ext4/fsync.c index 924726dcc85f..b7ea4433f4be 100644 --- a/fs/ext4/fsync.c +++ b/fs/ext4/fsync.c @@ -46,6 +46,7 @@ static int ext4_sync_parent(struct inode *inode) { struct dentry *dentry, *next; + struct mapping_metadata_bhs *mmb; int ret = 0; if (!ext4_test_inode_state(inode, EXT4_STATE_NEWENTRY)) @@ -68,9 +69,12 @@ static int ext4_sync_parent(struct inode *inode) * through ext4_evict_inode()) and so we are safe to flush * metadata blocks and the inode. */ - ret = mmb_sync(&EXT4_I(inode)->i_metadata_bhs); - if (ret) - break; + mmb = ext4_i_metadata_bhs(inode); + if (mmb) { + ret = mmb_sync(mmb); + if (ret) + break; + } ret = sync_inode_metadata(inode, 1); if (ret) break; @@ -89,7 +93,7 @@ static int ext4_fsync_nojournal(struct file *file, loff_t start, loff_t end, }; int ret; - ret = mmb_fsync_noflush(file, &EXT4_I(inode)->i_metadata_bhs, + ret = mmb_fsync_noflush(file, ext4_i_metadata_bhs(inode), start, end, datasync); if (ret) return ret; diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index ce99807c5f5b..e6acef486ee1 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -186,6 +186,8 @@ void ext4_evict_inode(struct inode *inode) if (EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL) ext4_evict_ea_inode(inode); if (inode->i_nlink) { + struct mapping_metadata_bhs *mmb; + /* * If there's dirty page will lead to data loss, user * could see stale data. @@ -195,9 +197,9 @@ void ext4_evict_inode(struct inode *inode) ext4_warning_inode(inode, "data will be lost"); truncate_inode_pages_final(&inode->i_data); - /* Avoid mballoc special inode which has no proper iops */ - if (!EXT4_SB(inode->i_sb)->s_journal) - mmb_sync(&EXT4_I(inode)->i_metadata_bhs); + mmb = ext4_i_metadata_bhs(inode); + if (mmb) + mmb_sync(mmb); goto no_delete; } @@ -3452,6 +3454,7 @@ static bool ext4_release_folio(struct folio *folio, gfp_t wait) static bool ext4_inode_datasync_dirty(struct inode *inode) { journal_t *journal = EXT4_SB(inode->i_sb)->s_journal; + struct mapping_metadata_bhs *mmb; if (journal) { if (jbd2_transaction_committed(journal, @@ -3462,8 +3465,9 @@ static bool ext4_inode_datasync_dirty(struct inode *inode) return true; } + mmb = ext4_i_metadata_bhs(inode); /* Any metadata buffers to write? */ - if (mmb_has_buffers(&EXT4_I(inode)->i_metadata_bhs)) + if (mmb && mmb_has_buffers(mmb)) return true; return inode_state_read_once(inode) & I_DIRTY_DATASYNC; } diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 245f67d10ded..8671fa1209dd 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -1430,7 +1430,7 @@ static struct inode *ext4_alloc_inode(struct super_block *sb) INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work); ext4_fc_init_inode(&ei->vfs_inode); spin_lock_init(&ei->i_fc_lock); - mmb_init(&ei->i_metadata_bhs, &ei->vfs_inode.i_data); + ei->i_metadata_bhs = NULL; #ifdef CONFIG_LOCKDEP lockdep_set_subclass(&ei->i_data_sem, I_DATA_SEM_NORMAL); #endif @@ -1451,6 +1451,7 @@ static int ext4_drop_inode(struct inode *inode) static void ext4_free_in_core_inode(struct inode *inode) { fscrypt_free_inode(inode); + kfree(ext4_i_metadata_bhs(inode)); if (!list_empty(&(EXT4_I(inode)->i_fc_list))) { pr_warn("%s: inode %llu still in fc list", __func__, inode->i_ino); @@ -1529,9 +1530,11 @@ static void destroy_inodecache(void) void ext4_clear_inode(struct inode *inode) { + struct mapping_metadata_bhs *mmb = ext4_i_metadata_bhs(inode); + ext4_fc_del(inode); - if (!EXT4_SB(inode->i_sb)->s_journal) - mmb_invalidate(&EXT4_I(inode)->i_metadata_bhs); + if (mmb) + mmb_invalidate(mmb); clear_inode(inode); ext4_discard_preallocations(inode); /* -- 2.51.0