From: Tahsin Erdogan Subject: Re: [PATCH v5 27/28] ext4: xattr inode deduplication Date: Tue, 20 Jun 2017 02:49:23 -0700 Message-ID: References: <6E41DA31-A524-4E0E-BD0B-5C994399BBC6@dilger.ca> <20170620090721.12480-1-tahsin@google.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Cc: linux-kernel@vger.kernel.org, Tahsin Erdogan To: Andreas Dilger , "Darrick J . Wong" , linux-ext4@vger.kernel.org Return-path: In-Reply-To: <20170620090721.12480-1-tahsin@google.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org Thanks Andreas for the feedback. Please see my responses below: > It would be preferable to allow a mount option like "no_mbcache" to disable > the use of shared xattrs. In the Lustre case at least, there will never be > shared large xattrs, and we've had a bunch of performance issues with mbcache > due to lock contention among many server threads doing concurrent lookups and > inserting many thousands of unique entries into the cache. I have put nombcache mount option in a separate patch ("[PATCH 32/32] ext4: add nombcache mount option"). I have named it nombcache instead of no_mbcache to be consistent with other no* options. Let me know if you prefer no_mbcache as the option name. > This should follow the existing convention of always using s_csum_seed to seed > the checksum, and change ext4_fill_super() to initialize s_csum_seed to ~0 if > ext4_has_metadata_csum() is false, or always use the same value regardless of > whether ext4_has_metadata_csum() is set or not. Done. > If it really necessary to have more than 2^32 references on a single shared > inode then it would be better to avoid the re-use of i_mtime, which breaks > the backref for unshared xattrs, and using i_size isn't enough of a guarantee > that this is the correct parent inode in case of on-disk corruption. I have now moved the lower 32bits of ref count from i_mtime to l_i_version. > Should this be contingent on ext4_has_metadata_csum() feature being enabled, or > alternately check if EXT4_XATTR_INODE_GET_PARENT() and i_generation match before > returning an error. This will allow a smooth transition from existing filesystems > that do not store the hash, but have only a single-use xattr inode with a parent > backref. I updated hash validation to fallback to parent backref check for backward compatibility. >> + /* Indirection block. */ >> + blocks += 1; > > Strictly speaking, this is only needed "if (blocks > EXT4_NDIR_BLOCKS)". Ack. I didn't think it was worth going through exact calculation in this case, let me know if you see value in doing that I also updated the comment to mention extents. >> + /* We may need to clone the existing xattr block in which case we need >> + * to increment ref counts for existing ea_inodes referenced by it. >> + */ > > Just to clarify here, in the case of cloning an existing xattr block, are the > refcounts being _incremented_ or _decremented_ on the existing ea_inodes? I'm > trying to figure out if we really need to have credits for both old and new > xattr inodes, as well as these additional credits. Since this is reserving > about 110 blocks for every setxattr, this can add significant pressure on the > journal if there are lots of threads creating files and/or setting xattrs. Cloning causes incrementing xattr inode references. >> +ext4_xattr_inode_cache_find(struct inode *inode, const void *value, >> + size_t value_len, u32 hash) >> { >> + struct inode *ea_inode; >> + struct mb_cache_entry *ce; >> + struct mb_cache *ea_inode_cache = EA_INODE_CACHE(inode); >> + void *ea_data = NULL; >> int err; > > This function should just return NULL if ea_inode_cache is NULL (e.g. in > the case of "no_mbcache" mount option). Done in later patch ("[PATCH 32/32] ext4: add nombcache mount option") > Should skip mb_cache if EA_INODE_CACHE(inode) is NULL, or have a wrapper > like ext4_xattr_inode_cache_insert() to match ext4_xattr_inode_cache_find() > that does the same. Added skip in patch ("[PATCH 32/32] ext4: add nombcache mount option") On Tue, Jun 20, 2017 at 2:07 AM, Tahsin Erdogan wrote: > Ext4 now supports xattr values that are up to 64k in size (vfs limit). > Large xattr values are stored in external inodes each one holding a > single value. Once written the data blocks of these inodes are immutable. > > The real world use cases are expected to have a lot of value duplication > such as inherited acls etc. To reduce data duplication on disk, this patch > implements a deduplicator that allows sharing of xattr inodes. > > The deduplication is based on an in-memory hash lookup that is a best > effort sharing scheme. When a xattr inode is read from disk (i.e. > getxattr() call), its crc32c hash is added to a hash table. Before > creating a new xattr inode for a value being set, the hash table is > checked to see if an existing inode holds an identical value. If such an > inode is found, the ref count on that inode is incremented. On value > removal the ref count is decremented and if it reaches zero the inode is > deleted. > > The quota charging for such inodes is manually managed. Every reference > holder is charged the full size as if there was no sharing happening. > This is consistent with how xattr blocks are also charged. > > Signed-off-by: Tahsin Erdogan > --- > v5: > - made ext4_meta_trans_blocks() static again since there are no > remaining users outside of inode.c > - initialize sbi->s_csum_seed when ea_inode feature is enabled > - use l_i_version to hold lower 32 bits of the xattr ref count. > This avoids clashes with old implementations which use i_mtime. > Since l_i_version is not available in HURD_COMPAT mode, fail mount > request when both ea_inode feature and HURD_COMPAT are set. > - when hash validation fails, fall back to old implementation > which has a backref to parent. > - fixed checkpatch.pl warning about using unsigned alone > > v4: > - eliminated xattr entry in the xattr inode to avoid complexity and > recursion in xattr update path. Now the ref count and hash are stored > in i_[c/m/a]time.tv_sec fields. > - some clean up in ext4_xattr_set_entry() to reduce code duplication and > complexity > > v3: > - use s_csum_seed for hash calculations when available > - return error on stored vs calculated hash mismatch > > v2: > - make dependency on crc32c dynamic > - update ext4_has_metadata_csum() and ext4_has_group_desc_csum() so that > they do not misinterpret existence of EXT4_SB(sb)->s_chksum_driver > > fs/ext4/acl.c | 5 +- > fs/ext4/ext4.h | 23 +- > fs/ext4/inode.c | 13 +- > fs/ext4/super.c | 37 +- > fs/ext4/xattr.c | 1038 +++++++++++++++++++++++++++++++++++++++++-------------- > fs/ext4/xattr.h | 17 +- > fs/mbcache.c | 9 +- > 7 files changed, 848 insertions(+), 294 deletions(-) > > diff --git a/fs/ext4/acl.c b/fs/ext4/acl.c > index 74f7ac539e00..8db03e5c78bc 100644 > --- a/fs/ext4/acl.c > +++ b/fs/ext4/acl.c > @@ -238,7 +238,10 @@ ext4_set_acl(struct inode *inode, struct posix_acl *acl, int type) > if (error) > return error; > retry: > - credits = ext4_xattr_set_credits(inode, acl_size); > + error = ext4_xattr_set_credits(inode, acl_size, &credits); > + if (error) > + return error; > + > handle = ext4_journal_start(inode, EXT4_HT_XATTR, credits); > if (IS_ERR(handle)) > return PTR_ERR(handle); > diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h > index d79d8d7bee88..59e9488c4876 100644 > --- a/fs/ext4/ext4.h > +++ b/fs/ext4/ext4.h > @@ -1517,6 +1517,7 @@ struct ext4_sb_info { > long s_es_nr_inode; > struct ext4_es_stats s_es_stats; > struct mb_cache *s_mb_cache; > + struct mb_cache *s_ea_inode_cache; > spinlock_t s_es_lock ____cacheline_aligned_in_smp; > > /* Ratelimit ext4 messages. */ > @@ -2099,7 +2100,11 @@ static inline struct ext4_inode *ext4_raw_inode(struct ext4_iloc *iloc) > return (struct ext4_inode *) (iloc->bh->b_data + iloc->offset); > } > > -#define ext4_is_quota_file(inode) IS_NOQUOTA(inode) > +static inline bool ext4_is_quota_file(struct inode *inode) > +{ > + return IS_NOQUOTA(inode) && > + !(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL); > +} > > /* > * This structure is stuffed into the struct file's private_data field > @@ -2482,7 +2487,6 @@ extern int ext4_truncate_restart_trans(handle_t *, struct inode *, int nblocks); > extern void ext4_set_inode_flags(struct inode *); > extern int ext4_alloc_da_blocks(struct inode *inode); > extern void ext4_set_aops(struct inode *inode); > -extern int ext4_meta_trans_blocks(struct inode *, int nrblocks, int chunk); > extern int ext4_writepage_trans_blocks(struct inode *); > extern int ext4_chunk_trans_blocks(struct inode *, int nrblocks); > extern int ext4_zero_partial_blocks(handle_t *handle, struct inode *inode, > @@ -2709,19 +2713,20 @@ extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group, > extern int ext4_register_li_request(struct super_block *sb, > ext4_group_t first_not_zeroed); > > -static inline int ext4_has_group_desc_csum(struct super_block *sb) > -{ > - return ext4_has_feature_gdt_csum(sb) || > - EXT4_SB(sb)->s_chksum_driver != NULL; > -} > - > static inline int ext4_has_metadata_csum(struct super_block *sb) > { > WARN_ON_ONCE(ext4_has_feature_metadata_csum(sb) && > !EXT4_SB(sb)->s_chksum_driver); > > - return (EXT4_SB(sb)->s_chksum_driver != NULL); > + return ext4_has_feature_metadata_csum(sb) && > + (EXT4_SB(sb)->s_chksum_driver != NULL); > } > + > +static inline int ext4_has_group_desc_csum(struct super_block *sb) > +{ > + return ext4_has_feature_gdt_csum(sb) || ext4_has_metadata_csum(sb); > +} > + > static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es) > { > return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) | > diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c > index cd007f9757d1..ea95bd9eab81 100644 > --- a/fs/ext4/inode.c > +++ b/fs/ext4/inode.c > @@ -139,6 +139,8 @@ static void ext4_invalidatepage(struct page *page, unsigned int offset, > unsigned int length); > static int __ext4_journalled_writepage(struct page *page, unsigned int len); > static int ext4_bh_delay_or_unwritten(handle_t *handle, struct buffer_head *bh); > +static int ext4_meta_trans_blocks(struct inode *inode, int lblocks, > + int pextents); > > /* > * Test whether an inode is a fast symlink. > @@ -4843,8 +4845,15 @@ struct inode *ext4_iget(struct super_block *sb, unsigned long ino) > } > brelse(iloc.bh); > ext4_set_inode_flags(inode); > - if (ei->i_flags & EXT4_EA_INODE_FL) > + > + if (ei->i_flags & EXT4_EA_INODE_FL) { > ext4_xattr_inode_set_class(inode); > + > + inode_lock(inode); > + inode->i_flags |= S_NOQUOTA; > + inode_unlock(inode); > + } > + > unlock_new_inode(inode); > return inode; > > @@ -5503,7 +5512,7 @@ static int ext4_index_trans_blocks(struct inode *inode, int lblocks, > * > * Also account for superblock, inode, quota and xattr blocks > */ > -int ext4_meta_trans_blocks(struct inode *inode, int lblocks, > +static int ext4_meta_trans_blocks(struct inode *inode, int lblocks, > int pextents) > { > ext4_group_t groups, ngroups = ext4_get_groups_count(inode->i_sb); > diff --git a/fs/ext4/super.c b/fs/ext4/super.c > index b02a23ec92ca..2bfacd737bb6 100644 > --- a/fs/ext4/super.c > +++ b/fs/ext4/super.c > @@ -927,6 +927,10 @@ static void ext4_put_super(struct super_block *sb) > invalidate_bdev(sbi->journal_bdev); > ext4_blkdev_remove(sbi); > } > + if (sbi->s_ea_inode_cache) { > + ext4_xattr_destroy_cache(sbi->s_ea_inode_cache); > + sbi->s_ea_inode_cache = NULL; > + } > if (sbi->s_mb_cache) { > ext4_xattr_destroy_cache(sbi->s_mb_cache); > sbi->s_mb_cache = NULL; > @@ -1178,7 +1182,10 @@ static int ext4_set_context(struct inode *inode, const void *ctx, size_t len, > if (res) > return res; > retry: > - credits = ext4_xattr_set_credits(inode, len); > + res = ext4_xattr_set_credits(inode, len, &credits); > + if (res) > + return res; > + > handle = ext4_journal_start(inode, EXT4_HT_MISC, credits); > if (IS_ERR(handle)) > return PTR_ERR(handle); > @@ -3445,7 +3452,8 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) > } > > /* Load the checksum driver */ > - if (ext4_has_feature_metadata_csum(sb)) { > + if (ext4_has_feature_metadata_csum(sb) || > + ext4_has_feature_ea_inode(sb)) { > sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0); > if (IS_ERR(sbi->s_chksum_driver)) { > ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver."); > @@ -3467,7 +3475,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) > /* Precompute checksum seed for all metadata */ > if (ext4_has_feature_csum_seed(sb)) > sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed); > - else if (ext4_has_metadata_csum(sb)) > + else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb)) > sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid, > sizeof(es->s_uuid)); > > @@ -3597,6 +3605,16 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) > "The Hurd can't support 64-bit file systems"); > goto failed_mount; > } > + > + /* > + * ea_inode feature uses l_i_version field which is not > + * available in HURD_COMPAT mode. > + */ > + if (ext4_has_feature_ea_inode(sb)) { > + ext4_msg(sb, KERN_ERR, > + "ea_inode feature is not supported for Hurd"); > + goto failed_mount; > + } > } > > if (IS_EXT2_SB(sb)) { > @@ -4067,6 +4085,15 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) > goto failed_mount_wq; > } > > + if (ext4_has_feature_ea_inode(sb)) { > + sbi->s_ea_inode_cache = ext4_xattr_create_cache(); > + if (!sbi->s_ea_inode_cache) { > + ext4_msg(sb, KERN_ERR, > + "Failed to create an s_ea_inode_cache"); > + goto failed_mount_wq; > + } > + } > + > if ((DUMMY_ENCRYPTION_ENABLED(sbi) || ext4_has_feature_encrypt(sb)) && > (blocksize != PAGE_SIZE)) { > ext4_msg(sb, KERN_ERR, > @@ -4296,6 +4323,10 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) > if (EXT4_SB(sb)->rsv_conversion_wq) > destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq); > failed_mount_wq: > + if (sbi->s_ea_inode_cache) { > + ext4_xattr_destroy_cache(sbi->s_ea_inode_cache); > + sbi->s_ea_inode_cache = NULL; > + } > if (sbi->s_mb_cache) { > ext4_xattr_destroy_cache(sbi->s_mb_cache); > sbi->s_mb_cache = NULL; > diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c > index 0484df8dadd1..d7e60358ec91 100644 > --- a/fs/ext4/xattr.c > +++ b/fs/ext4/xattr.c > @@ -108,6 +108,9 @@ const struct xattr_handler *ext4_xattr_handlers[] = { > #define EXT4_GET_MB_CACHE(inode) (((struct ext4_sb_info *) \ > inode->i_sb->s_fs_info)->s_mb_cache) > > +#define EA_INODE_CACHE(inode) (((struct ext4_sb_info *) \ > + inode->i_sb->s_fs_info)->s_ea_inode_cache) > + > static int > ext4_expand_inode_array(struct ext4_xattr_inode_array **ea_inode_array, > struct inode *inode); > @@ -280,15 +283,44 @@ ext4_xattr_find_entry(struct ext4_xattr_entry **pentry, int name_index, > return cmp ? -ENODATA : 0; > } > > +static u32 > +ext4_xattr_inode_hash(struct ext4_sb_info *sbi, const void *buffer, size_t size) > +{ > + return ext4_chksum(sbi, sbi->s_csum_seed, buffer, size); > +} > + > +static u64 ext4_xattr_inode_get_ref(struct inode *ea_inode) > +{ > + return ((u64)ea_inode->i_ctime.tv_sec << 32) | > + ((u32)ea_inode->i_version); > +} > + > +static void ext4_xattr_inode_set_ref(struct inode *ea_inode, u64 ref_count) > +{ > + ea_inode->i_ctime.tv_sec = (u32)(ref_count >> 32); > + ea_inode->i_version = (u32)ref_count; > +} > + > +static u32 ext4_xattr_inode_get_hash(struct inode *ea_inode) > +{ > + return (u32)ea_inode->i_atime.tv_sec; > +} > + > +static void ext4_xattr_inode_set_hash(struct inode *ea_inode, u32 hash) > +{ > + ea_inode->i_atime.tv_sec = hash; > +} > + > /* > * Read the EA value from an inode. > */ > static int ext4_xattr_inode_read(struct inode *ea_inode, void *buf, size_t size) > { > unsigned long block = 0; > - struct buffer_head *bh = NULL; > + struct buffer_head *bh; > int blocksize = ea_inode->i_sb->s_blocksize; > size_t csize, copied = 0; > + void *copy_pos = buf; > > while (copied < size) { > csize = (size - copied) > blocksize ? blocksize : size - copied; > @@ -298,10 +330,10 @@ static int ext4_xattr_inode_read(struct inode *ea_inode, void *buf, size_t size) > if (!bh) > return -EFSCORRUPTED; > > - memcpy(buf, bh->b_data, csize); > + memcpy(copy_pos, bh->b_data, csize); > brelse(bh); > > - buf += csize; > + copy_pos += csize; > block += 1; > copied += csize; > } > @@ -317,29 +349,24 @@ static int ext4_xattr_inode_iget(struct inode *parent, unsigned long ea_ino, > inode = ext4_iget(parent->i_sb, ea_ino); > if (IS_ERR(inode)) { > err = PTR_ERR(inode); > - ext4_error(parent->i_sb, "error while reading EA inode %lu " > - "err=%d", ea_ino, err); > + ext4_error(parent->i_sb, > + "error while reading EA inode %lu err=%d", ea_ino, > + err); > return err; > } > > if (is_bad_inode(inode)) { > - ext4_error(parent->i_sb, "error while reading EA inode %lu " > - "is_bad_inode", ea_ino); > + ext4_error(parent->i_sb, > + "error while reading EA inode %lu is_bad_inode", > + ea_ino); > err = -EIO; > goto error; > } > > - if (EXT4_XATTR_INODE_GET_PARENT(inode) != parent->i_ino || > - inode->i_generation != parent->i_generation) { > - ext4_error(parent->i_sb, "Backpointer from EA inode %lu " > - "to parent is invalid.", ea_ino); > - err = -EINVAL; > - goto error; > - } > - > if (!(EXT4_I(inode)->i_flags & EXT4_EA_INODE_FL)) { > - ext4_error(parent->i_sb, "EA inode %lu does not have " > - "EXT4_EA_INODE_FL flag set.\n", ea_ino); > + ext4_error(parent->i_sb, > + "EA inode %lu does not have EXT4_EA_INODE_FL flag", > + ea_ino); > err = -EINVAL; > goto error; > } > @@ -351,6 +378,20 @@ static int ext4_xattr_inode_iget(struct inode *parent, unsigned long ea_ino, > return err; > } > > +static int > +ext4_xattr_inode_verify_hash(struct inode *ea_inode, void *buffer, size_t size) > +{ > + u32 hash; > + > + /* Verify stored hash matches calculated hash. */ > + hash = ext4_xattr_inode_hash(EXT4_SB(ea_inode->i_sb), buffer, size); > + if (hash != ext4_xattr_inode_get_hash(ea_inode)) > + return -EFSCORRUPTED; > + return 0; > +} > + > +#define EXT4_XATTR_INODE_GET_PARENT(inode) ((__u32)(inode)->i_mtime.tv_sec) > + > /* > * Read the value from the EA inode. > */ > @@ -358,17 +399,53 @@ static int > ext4_xattr_inode_get(struct inode *inode, unsigned long ea_ino, void *buffer, > size_t size) > { > + struct mb_cache *ea_inode_cache = EA_INODE_CACHE(inode); > struct inode *ea_inode; > - int ret; > + int err; > > - ret = ext4_xattr_inode_iget(inode, ea_ino, &ea_inode); > - if (ret) > - return ret; > + err = ext4_xattr_inode_iget(inode, ea_ino, &ea_inode); > + if (err) { > + ea_inode = NULL; > + goto out; > + } > > - ret = ext4_xattr_inode_read(ea_inode, buffer, size); > - iput(ea_inode); > + if (i_size_read(ea_inode) != size) { > + ext4_warning_inode(ea_inode, > + "ea_inode file size=%llu entry size=%zu", > + i_size_read(ea_inode), size); > + err = -EFSCORRUPTED; > + goto out; > + } > > - return ret; > + err = ext4_xattr_inode_read(ea_inode, buffer, size); > + if (err) > + goto out; > + > + err = ext4_xattr_inode_verify_hash(ea_inode, buffer, size); > + /* > + * Compatibility check for old Lustre ea_inode implementation. Old > + * version does not have hash validation, but it has a backpointer > + * from ea_inode to the parent inode. > + */ > + if (err == -EFSCORRUPTED) { > + if (EXT4_XATTR_INODE_GET_PARENT(ea_inode) != inode->i_ino || > + ea_inode->i_generation != inode->i_generation) { > + ext4_warning_inode(ea_inode, > + "EA inode hash validation failed"); > + goto out; > + } > + /* Do not add ea_inode to the cache. */ > + ea_inode_cache = NULL; > + } else if (err) > + goto out; > + > + if (ea_inode_cache) > + mb_cache_entry_create(ea_inode_cache, GFP_NOFS, > + ext4_xattr_inode_get_hash(ea_inode), > + ea_inode->i_ino, true /* reusable */); > +out: > + iput(ea_inode); > + return err; > } > > static int > @@ -657,6 +734,101 @@ static void ext4_xattr_update_super_block(handle_t *handle, > } > } > > +static inline size_t round_up_cluster(struct inode *inode, size_t length) > +{ > + struct super_block *sb = inode->i_sb; > + size_t cluster_size = 1 << (EXT4_SB(sb)->s_cluster_bits + > + inode->i_blkbits); > + size_t mask = ~(cluster_size - 1); > + > + return (length + cluster_size - 1) & mask; > +} > + > +static int ext4_xattr_inode_alloc_quota(struct inode *inode, size_t len) > +{ > + int err; > + > + err = dquot_alloc_inode(inode); > + if (err) > + return err; > + err = dquot_alloc_space_nodirty(inode, round_up_cluster(inode, len)); > + if (err) > + dquot_free_inode(inode); > + return err; > +} > + > +static void ext4_xattr_inode_free_quota(struct inode *inode, size_t len) > +{ > + dquot_free_space_nodirty(inode, round_up_cluster(inode, len)); > + dquot_free_inode(inode); > +} > + > +static int __ext4_xattr_set_credits(struct super_block *sb, > + struct buffer_head *block_bh, > + size_t value_len) > +{ > + int credits; > + int blocks; > + > + /* > + * 1) Owner inode update > + * 2) Ref count update on old xattr block > + * 3) new xattr block > + * 4) block bitmap update for new xattr block > + * 5) group descriptor for new xattr block > + */ > + credits = 5; > + > + /* We are done if ea_inode feature is not enabled. */ > + if (!ext4_has_feature_ea_inode(sb)) > + return credits; > + > + /* New ea_inode, inode map, block bitmap, group descriptor. */ > + credits += 4; > + > + /* Data blocks. */ > + blocks = (value_len + sb->s_blocksize - 1) >> sb->s_blocksize_bits; > + > + /* Indirection block or one level of extent tree. */ > + blocks += 1; > + > + /* Block bitmap and group descriptor updates for each block. */ > + credits += blocks * 2; > + > + /* Blocks themselves. */ > + credits += blocks; > + > + /* Dereference ea_inode holding old xattr value. > + * Old ea_inode, inode map, block bitmap, group descriptor. > + */ > + credits += 4; > + > + /* Data blocks for old ea_inode. */ > + blocks = XATTR_SIZE_MAX >> sb->s_blocksize_bits; > + > + /* Indirection block or one level of extent tree for old ea_inode. */ > + blocks += 1; > + > + /* Block bitmap and group descriptor updates for each block. */ > + credits += blocks * 2; > + > + /* Quota updates. */ > + credits += EXT4_MAXQUOTAS_TRANS_BLOCKS(sb); > + > + /* We may need to clone the existing xattr block in which case we need > + * to increment ref counts for existing ea_inodes referenced by it. > + */ > + if (block_bh) { > + struct ext4_xattr_entry *entry = BFIRST(block_bh); > + > + for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) > + if (entry->e_value_inum) > + /* Ref count update on ea_inode. */ > + credits += 1; > + } > + return credits; > +} > + > static int ext4_xattr_ensure_credits(handle_t *handle, struct inode *inode, > int credits, struct buffer_head *bh, > bool dirty, bool block_csum) > @@ -706,12 +878,140 @@ static int ext4_xattr_ensure_credits(handle_t *handle, struct inode *inode, > return 0; > } > > +static int ext4_xattr_inode_update_ref(handle_t *handle, struct inode *ea_inode, > + int ref_change) > +{ > + struct mb_cache *ea_inode_cache = EA_INODE_CACHE(ea_inode); > + struct ext4_iloc iloc; > + s64 ref_count; > + u32 hash; > + int ret; > + > + inode_lock(ea_inode); > + > + ret = ext4_reserve_inode_write(handle, ea_inode, &iloc); > + if (ret) { > + iloc.bh = NULL; > + goto out; > + } > + > + ref_count = ext4_xattr_inode_get_ref(ea_inode); > + ref_count += ref_change; > + ext4_xattr_inode_set_ref(ea_inode, ref_count); > + > + if (ref_change > 0) { > + WARN_ONCE(ref_count <= 0, "EA inode %lu ref_count=%lld", > + ea_inode->i_ino, ref_count); > + > + if (ref_count == 1) { > + WARN_ONCE(ea_inode->i_nlink, "EA inode %lu i_nlink=%u", > + ea_inode->i_ino, ea_inode->i_nlink); > + > + set_nlink(ea_inode, 1); > + ext4_orphan_del(handle, ea_inode); > + > + hash = ext4_xattr_inode_get_hash(ea_inode); > + mb_cache_entry_create(ea_inode_cache, GFP_NOFS, hash, > + ea_inode->i_ino, > + true /* reusable */); > + } > + } else { > + WARN_ONCE(ref_count < 0, "EA inode %lu ref_count=%lld", > + ea_inode->i_ino, ref_count); > + > + if (ref_count == 0) { > + WARN_ONCE(ea_inode->i_nlink != 1, > + "EA inode %lu i_nlink=%u", > + ea_inode->i_ino, ea_inode->i_nlink); > + > + clear_nlink(ea_inode); > + ext4_orphan_add(handle, ea_inode); > + > + hash = ext4_xattr_inode_get_hash(ea_inode); > + mb_cache_entry_delete(ea_inode_cache, hash, > + ea_inode->i_ino); > + } > + } > + > + ret = ext4_mark_iloc_dirty(handle, ea_inode, &iloc); > + iloc.bh = NULL; > + if (ret) > + ext4_warning_inode(ea_inode, > + "ext4_mark_iloc_dirty() failed ret=%d", ret); > +out: > + brelse(iloc.bh); > + inode_unlock(ea_inode); > + return ret; > +} > + > +static int ext4_xattr_inode_inc_ref(handle_t *handle, struct inode *ea_inode) > +{ > + return ext4_xattr_inode_update_ref(handle, ea_inode, 1); > +} > + > +static int ext4_xattr_inode_dec_ref(handle_t *handle, struct inode *ea_inode) > +{ > + return ext4_xattr_inode_update_ref(handle, ea_inode, -1); > +} > + > +static int ext4_xattr_inode_inc_ref_all(handle_t *handle, struct inode *parent, > + struct ext4_xattr_entry *first) > +{ > + struct inode *ea_inode; > + struct ext4_xattr_entry *entry; > + struct ext4_xattr_entry *failed_entry; > + unsigned int ea_ino; > + int err, saved_err; > + > + for (entry = first; !IS_LAST_ENTRY(entry); > + entry = EXT4_XATTR_NEXT(entry)) { > + if (!entry->e_value_inum) > + continue; > + ea_ino = le32_to_cpu(entry->e_value_inum); > + err = ext4_xattr_inode_iget(parent, ea_ino, &ea_inode); > + if (err) > + goto cleanup; > + err = ext4_xattr_inode_inc_ref(handle, ea_inode); > + if (err) { > + ext4_warning_inode(ea_inode, "inc ref error %d", err); > + iput(ea_inode); > + goto cleanup; > + } > + iput(ea_inode); > + } > + return 0; > + > +cleanup: > + saved_err = err; > + failed_entry = entry; > + > + for (entry = first; entry != failed_entry; > + entry = EXT4_XATTR_NEXT(entry)) { > + if (!entry->e_value_inum) > + continue; > + ea_ino = le32_to_cpu(entry->e_value_inum); > + err = ext4_xattr_inode_iget(parent, ea_ino, &ea_inode); > + if (err) { > + ext4_warning(parent->i_sb, > + "cleanup ea_ino %u iget error %d", ea_ino, > + err); > + continue; > + } > + err = ext4_xattr_inode_dec_ref(handle, ea_inode); > + if (err) > + ext4_warning_inode(ea_inode, "cleanup dec ref error %d", > + err); > + iput(ea_inode); > + } > + return saved_err; > +} > + > static void > -ext4_xattr_inode_remove_all(handle_t *handle, struct inode *parent, > - struct buffer_head *bh, > - struct ext4_xattr_entry *first, bool block_csum, > - struct ext4_xattr_inode_array **ea_inode_array, > - int extra_credits) > +ext4_xattr_inode_dec_ref_all(handle_t *handle, struct inode *parent, > + struct buffer_head *bh, > + struct ext4_xattr_entry *first, bool block_csum, > + struct ext4_xattr_inode_array **ea_inode_array, > + int extra_credits, bool skip_quota) > { > struct inode *ea_inode; > struct ext4_xattr_entry *entry; > @@ -748,10 +1048,16 @@ ext4_xattr_inode_remove_all(handle_t *handle, struct inode *parent, > continue; > } > > - inode_lock(ea_inode); > - clear_nlink(ea_inode); > - ext4_orphan_add(handle, ea_inode); > - inode_unlock(ea_inode); > + err = ext4_xattr_inode_dec_ref(handle, ea_inode); > + if (err) { > + ext4_warning_inode(ea_inode, "ea_inode dec ref err=%d", > + err); > + continue; > + } > + > + if (!skip_quota) > + ext4_xattr_inode_free_quota(parent, > + le32_to_cpu(entry->e_value_size)); > > /* > * Forget about ea_inode within the same transaction that > @@ -785,7 +1091,9 @@ ext4_xattr_inode_remove_all(handle_t *handle, struct inode *parent, > */ > static void > ext4_xattr_release_block(handle_t *handle, struct inode *inode, > - struct buffer_head *bh) > + struct buffer_head *bh, > + struct ext4_xattr_inode_array **ea_inode_array, > + int extra_credits) > { > struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); > u32 hash, ref; > @@ -808,6 +1116,14 @@ ext4_xattr_release_block(handle_t *handle, struct inode *inode, > mb_cache_entry_delete(ext4_mb_cache, hash, bh->b_blocknr); > get_bh(bh); > unlock_buffer(bh); > + > + if (ext4_has_feature_ea_inode(inode->i_sb)) > + ext4_xattr_inode_dec_ref_all(handle, inode, bh, > + BFIRST(bh), > + true /* block_csum */, > + ea_inode_array, > + extra_credits, > + true /* skip_quota */); > ext4_free_blocks(handle, inode, bh, 0, 1, > EXT4_FREE_BLOCKS_METADATA | > EXT4_FREE_BLOCKS_FORGET); > @@ -879,8 +1195,8 @@ static int ext4_xattr_inode_write(handle_t *handle, struct inode *ea_inode, > { > struct buffer_head *bh = NULL; > unsigned long block = 0; > - unsigned blocksize = ea_inode->i_sb->s_blocksize; > - unsigned max_blocks = (bufsize + blocksize - 1) >> ea_inode->i_blkbits; > + int blocksize = ea_inode->i_sb->s_blocksize; > + int max_blocks = (bufsize + blocksize - 1) >> ea_inode->i_blkbits; > int csize, wsize = 0; > int ret = 0; > int retries = 0; > @@ -948,7 +1264,7 @@ static int ext4_xattr_inode_write(handle_t *handle, struct inode *ea_inode, > * Create an inode to store the value of a large EA. > */ > static struct inode *ext4_xattr_inode_create(handle_t *handle, > - struct inode *inode) > + struct inode *inode, u32 hash) > { > struct inode *ea_inode = NULL; > uid_t owner[2] = { i_uid_read(inode), i_gid_read(inode) }; > @@ -966,67 +1282,115 @@ static struct inode *ext4_xattr_inode_create(handle_t *handle, > ea_inode->i_fop = &ext4_file_operations; > ext4_set_aops(ea_inode); > ext4_xattr_inode_set_class(ea_inode); > - ea_inode->i_generation = inode->i_generation; > - EXT4_I(ea_inode)->i_flags |= EXT4_EA_INODE_FL; > - > - /* > - * A back-pointer from EA inode to parent inode will be useful > - * for e2fsck. > - */ > - EXT4_XATTR_INODE_SET_PARENT(ea_inode, inode->i_ino); > unlock_new_inode(ea_inode); > - err = ext4_inode_attach_jinode(ea_inode); > + ext4_xattr_inode_set_ref(ea_inode, 1); > + ext4_xattr_inode_set_hash(ea_inode, hash); > + err = ext4_mark_inode_dirty(handle, ea_inode); > + if (!err) > + err = ext4_inode_attach_jinode(ea_inode); > if (err) { > iput(ea_inode); > return ERR_PTR(err); > } > + > + /* > + * Xattr inodes are shared therefore quota charging is performed > + * at a higher level. > + */ > + dquot_free_inode(ea_inode); > + dquot_drop(ea_inode); > + inode_lock(ea_inode); > + ea_inode->i_flags |= S_NOQUOTA; > + inode_unlock(ea_inode); > } > > return ea_inode; > } > > -/* > - * Unlink the inode storing the value of the EA. > - */ > -int ext4_xattr_inode_unlink(struct inode *inode, unsigned long ea_ino) > +static struct inode * > +ext4_xattr_inode_cache_find(struct inode *inode, const void *value, > + size_t value_len, u32 hash) > { > - struct inode *ea_inode = NULL; > - int err; > + struct inode *ea_inode; > + struct mb_cache_entry *ce; > + struct mb_cache *ea_inode_cache = EA_INODE_CACHE(inode); > + void *ea_data; > > - err = ext4_xattr_inode_iget(inode, ea_ino, &ea_inode); > - if (err) > - return err; > + ce = mb_cache_entry_find_first(ea_inode_cache, hash); > + if (!ce) > + return NULL; > > - clear_nlink(ea_inode); > - iput(ea_inode); > + ea_data = ext4_kvmalloc(value_len, GFP_NOFS); > + if (!ea_data) { > + mb_cache_entry_put(ea_inode_cache, ce); > + return NULL; > + } > > - return 0; > + while (ce) { > + ea_inode = ext4_iget(inode->i_sb, ce->e_value); > + if (!IS_ERR(ea_inode) && > + !is_bad_inode(ea_inode) && > + (EXT4_I(ea_inode)->i_flags & EXT4_EA_INODE_FL) && > + i_size_read(ea_inode) == value_len && > + !ext4_xattr_inode_read(ea_inode, ea_data, value_len) && > + !ext4_xattr_inode_verify_hash(ea_inode, ea_data, > + value_len) && > + !memcmp(value, ea_data, value_len)) { > + mb_cache_entry_touch(ea_inode_cache, ce); > + mb_cache_entry_put(ea_inode_cache, ce); > + kvfree(ea_data); > + return ea_inode; > + } > + > + if (!IS_ERR(ea_inode)) > + iput(ea_inode); > + ce = mb_cache_entry_find_next(ea_inode_cache, ce); > + } > + kvfree(ea_data); > + return NULL; > } > > /* > * Add value of the EA in an inode. > */ > -static int ext4_xattr_inode_set(handle_t *handle, struct inode *inode, > - unsigned long *ea_ino, const void *value, > - size_t value_len) > +static int ext4_xattr_inode_lookup_create(handle_t *handle, struct inode *inode, > + const void *value, size_t value_len, > + struct inode **ret_inode) > { > struct inode *ea_inode; > + u32 hash; > int err; > > + hash = ext4_xattr_inode_hash(EXT4_SB(inode->i_sb), value, value_len); > + ea_inode = ext4_xattr_inode_cache_find(inode, value, value_len, hash); > + if (ea_inode) { > + err = ext4_xattr_inode_inc_ref(handle, ea_inode); > + if (err) { > + iput(ea_inode); > + return err; > + } > + > + *ret_inode = ea_inode; > + return 0; > + } > + > /* Create an inode for the EA value */ > - ea_inode = ext4_xattr_inode_create(handle, inode); > + ea_inode = ext4_xattr_inode_create(handle, inode, hash); > if (IS_ERR(ea_inode)) > return PTR_ERR(ea_inode); > > err = ext4_xattr_inode_write(handle, ea_inode, value, value_len); > - if (err) > - clear_nlink(ea_inode); > - else > - *ea_ino = ea_inode->i_ino; > + if (err) { > + ext4_xattr_inode_dec_ref(handle, ea_inode); > + iput(ea_inode); > + return err; > + } > > - iput(ea_inode); > + mb_cache_entry_create(EA_INODE_CACHE(inode), GFP_NOFS, hash, > + ea_inode->i_ino, true /* reusable */); > > - return err; > + *ret_inode = ea_inode; > + return 0; > } > > static int ext4_xattr_set_entry(struct ext4_xattr_info *i, > @@ -1034,9 +1398,37 @@ static int ext4_xattr_set_entry(struct ext4_xattr_info *i, > handle_t *handle, struct inode *inode) > { > struct ext4_xattr_entry *last; > - size_t free, min_offs = s->end - s->base, name_len = strlen(i->name); > + struct ext4_xattr_entry *here = s->here; > + size_t min_offs = s->end - s->base, name_len = strlen(i->name); > int in_inode = i->in_inode; > - int rc; > + struct inode *old_ea_inode = NULL; > + struct inode *new_ea_inode = NULL; > + size_t old_size, new_size; > + int ret; > + > + /* Space used by old and new values. */ > + old_size = (!s->not_found && !here->e_value_inum) ? > + EXT4_XATTR_SIZE(le32_to_cpu(here->e_value_size)) : 0; > + new_size = (i->value && !in_inode) ? EXT4_XATTR_SIZE(i->value_len) : 0; > + > + /* > + * Optimization for the simple case when old and new values have the > + * same padded sizes. Not applicable if external inodes are involved. > + */ > + if (new_size && new_size == old_size) { > + size_t offs = le16_to_cpu(here->e_value_offs); > + void *val = s->base + offs; > + > + here->e_value_size = cpu_to_le32(i->value_len); > + if (i->value == EXT4_ZERO_XATTR_VALUE) { > + memset(val, 0, new_size); > + } else { > + memcpy(val, i->value, i->value_len); > + /* Clear padding bytes. */ > + memset(val + i->value_len, 0, new_size - i->value_len); > + } > + return 0; > + } > > /* Compute min_offs and last. */ > last = s->first; > @@ -1047,122 +1439,148 @@ static int ext4_xattr_set_entry(struct ext4_xattr_info *i, > min_offs = offs; > } > } > - free = min_offs - ((void *)last - s->base) - sizeof(__u32); > - if (!s->not_found) { > - if (!in_inode && > - !s->here->e_value_inum && s->here->e_value_size) { > - size_t size = le32_to_cpu(s->here->e_value_size); > - free += EXT4_XATTR_SIZE(size); > - } > - free += EXT4_XATTR_LEN(name_len); > - } > + > + /* Check whether we have enough space. */ > if (i->value) { > - size_t value_len = EXT4_XATTR_SIZE(i->value_len); > + size_t free; > > - if (in_inode) > - value_len = 0; > + free = min_offs - ((void *)last - s->base) - sizeof(__u32); > + if (!s->not_found) > + free += EXT4_XATTR_LEN(name_len) + old_size; > > - if (free < EXT4_XATTR_LEN(name_len) + value_len) > - return -ENOSPC; > + if (free < EXT4_XATTR_LEN(name_len) + new_size) { > + ret = -ENOSPC; > + goto out; > + } > } > > - if (i->value && s->not_found) { > - /* Insert the new name. */ > - size_t size = EXT4_XATTR_LEN(name_len); > - size_t rest = (void *)last - (void *)s->here + sizeof(__u32); > - memmove((void *)s->here + size, s->here, rest); > - memset(s->here, 0, size); > - s->here->e_name_index = i->name_index; > - s->here->e_name_len = name_len; > - memcpy(s->here->e_name, i->name, name_len); > - } else { > - if (!s->here->e_value_inum && s->here->e_value_size && > - s->here->e_value_offs > 0) { > - void *first_val = s->base + min_offs; > - size_t offs = le16_to_cpu(s->here->e_value_offs); > - void *val = s->base + offs; > - size_t size = EXT4_XATTR_SIZE( > - le32_to_cpu(s->here->e_value_size)); > - > - if (i->value && size == EXT4_XATTR_SIZE(i->value_len)) { > - /* The old and the new value have the same > - size. Just replace. */ > - s->here->e_value_size = > - cpu_to_le32(i->value_len); > - if (i->value == EXT4_ZERO_XATTR_VALUE) { > - memset(val, 0, size); > - } else { > - /* Clear pad bytes first. */ > - memset(val + size - EXT4_XATTR_PAD, 0, > - EXT4_XATTR_PAD); > - memcpy(val, i->value, i->value_len); > - } > - return 0; > - } > + /* > + * Getting access to old and new ea inodes is subject to failures. > + * Finish that work before doing any modifications to the xattr data. > + */ > + if (!s->not_found && here->e_value_inum) { > + ret = ext4_xattr_inode_iget(inode, > + le32_to_cpu(here->e_value_inum), > + &old_ea_inode); > + if (ret) { > + old_ea_inode = NULL; > + goto out; > + } > + } > + if (i->value && in_inode) { > + WARN_ON_ONCE(!i->value_len); > > - /* Remove the old value. */ > - memmove(first_val + size, first_val, val - first_val); > - memset(first_val, 0, size); > - s->here->e_value_size = 0; > - s->here->e_value_offs = 0; > - min_offs += size; > - > - /* Adjust all value offsets. */ > - last = s->first; > - while (!IS_LAST_ENTRY(last)) { > - size_t o = le16_to_cpu(last->e_value_offs); > - if (!last->e_value_inum && > - last->e_value_size && o < offs) > - last->e_value_offs = > - cpu_to_le16(o + size); > - last = EXT4_XATTR_NEXT(last); > - } > + ret = ext4_xattr_inode_alloc_quota(inode, i->value_len); > + if (ret) > + goto out; > + > + ret = ext4_xattr_inode_lookup_create(handle, inode, i->value, > + i->value_len, > + &new_ea_inode); > + if (ret) { > + new_ea_inode = NULL; > + ext4_xattr_inode_free_quota(inode, i->value_len); > + goto out; > } > - if (s->here->e_value_inum) { > - ext4_xattr_inode_unlink(inode, > - le32_to_cpu(s->here->e_value_inum)); > - s->here->e_value_inum = 0; > + } > + > + if (old_ea_inode) { > + /* We are ready to release ref count on the old_ea_inode. */ > + ret = ext4_xattr_inode_dec_ref(handle, old_ea_inode); > + if (ret) { > + /* Release newly required ref count on new_ea_inode. */ > + if (new_ea_inode) { > + int err; > + > + err = ext4_xattr_inode_dec_ref(handle, > + new_ea_inode); > + if (err) > + ext4_warning_inode(new_ea_inode, > + "dec ref new_ea_inode err=%d", > + err); > + ext4_xattr_inode_free_quota(inode, > + i->value_len); > + } > + goto out; > } > - if (!i->value) { > - /* Remove the old name. */ > - size_t size = EXT4_XATTR_LEN(name_len); > - last = ENTRY((void *)last - size); > - memmove(s->here, (void *)s->here + size, > - (void *)last - (void *)s->here + sizeof(__u32)); > - memset(last, 0, size); > + > + ext4_xattr_inode_free_quota(inode, > + le32_to_cpu(here->e_value_size)); > + } > + > + /* No failures allowed past this point. */ > + > + if (!s->not_found && here->e_value_offs) { > + /* Remove the old value. */ > + void *first_val = s->base + min_offs; > + size_t offs = le16_to_cpu(here->e_value_offs); > + void *val = s->base + offs; > + > + memmove(first_val + old_size, first_val, val - first_val); > + memset(first_val, 0, old_size); > + min_offs += old_size; > + > + /* Adjust all value offsets. */ > + last = s->first; > + while (!IS_LAST_ENTRY(last)) { > + size_t o = le16_to_cpu(last->e_value_offs); > + > + if (!last->e_value_inum && > + last->e_value_size && o < offs) > + last->e_value_offs = cpu_to_le16(o + old_size); > + last = EXT4_XATTR_NEXT(last); > } > } > > + if (!i->value) { > + /* Remove old name. */ > + size_t size = EXT4_XATTR_LEN(name_len); > + > + last = ENTRY((void *)last - size); > + memmove(here, (void *)here + size, > + (void *)last - (void *)here + sizeof(__u32)); > + memset(last, 0, size); > + } else if (s->not_found) { > + /* Insert new name. */ > + size_t size = EXT4_XATTR_LEN(name_len); > + size_t rest = (void *)last - (void *)here + sizeof(__u32); > + > + memmove((void *)here + size, here, rest); > + memset(here, 0, size); > + here->e_name_index = i->name_index; > + here->e_name_len = name_len; > + memcpy(here->e_name, i->name, name_len); > + } else { > + /* This is an update, reset value info. */ > + here->e_value_inum = 0; > + here->e_value_offs = 0; > + here->e_value_size = 0; > + } > + > if (i->value) { > - /* Insert the new value. */ > + /* Insert new value. */ > if (in_inode) { > - unsigned long ea_ino = > - le32_to_cpu(s->here->e_value_inum); > - rc = ext4_xattr_inode_set(handle, inode, &ea_ino, > - i->value, i->value_len); > - if (rc) > - goto out; > - s->here->e_value_inum = cpu_to_le32(ea_ino); > - s->here->e_value_offs = 0; > + here->e_value_inum = cpu_to_le32(new_ea_inode->i_ino); > } else if (i->value_len) { > - size_t size = EXT4_XATTR_SIZE(i->value_len); > - void *val = s->base + min_offs - size; > - s->here->e_value_offs = cpu_to_le16(min_offs - size); > - s->here->e_value_inum = 0; > + void *val = s->base + min_offs - new_size; > + > + here->e_value_offs = cpu_to_le16(min_offs - new_size); > if (i->value == EXT4_ZERO_XATTR_VALUE) { > - memset(val, 0, size); > + memset(val, 0, new_size); > } else { > - /* Clear the pad bytes first. */ > - memset(val + size - EXT4_XATTR_PAD, 0, > - EXT4_XATTR_PAD); > memcpy(val, i->value, i->value_len); > + /* Clear padding bytes. */ > + memset(val + i->value_len, 0, > + new_size - i->value_len); > } > } > - s->here->e_value_size = cpu_to_le32(i->value_len); > + here->e_value_size = cpu_to_le32(i->value_len); > } > - > + ret = 0; > out: > - return rc; > + iput(old_ea_inode); > + iput(new_ea_inode); > + return ret; > } > > struct ext4_xattr_block_find { > @@ -1224,6 +1642,8 @@ ext4_xattr_block_set(handle_t *handle, struct inode *inode, > struct mb_cache_entry *ce = NULL; > int error = 0; > struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); > + struct inode *ea_inode = NULL; > + size_t old_ea_inode_size = 0; > > #define header(x) ((struct ext4_xattr_header *)(x)) > > @@ -1278,6 +1698,24 @@ ext4_xattr_block_set(handle_t *handle, struct inode *inode, > header(s->base)->h_refcount = cpu_to_le32(1); > s->here = ENTRY(s->base + offset); > s->end = s->base + bs->bh->b_size; > + > + /* > + * If existing entry points to an xattr inode, we need > + * to prevent ext4_xattr_set_entry() from decrementing > + * ref count on it because the reference belongs to the > + * original block. In this case, make the entry look > + * like it has an empty value. > + */ > + if (!s->not_found && s->here->e_value_inum) { > + /* > + * Defer quota free call for previous inode > + * until success is guaranteed. > + */ > + old_ea_inode_size = le32_to_cpu( > + s->here->e_value_size); > + s->here->e_value_inum = 0; > + s->here->e_value_size = 0; > + } > } > } else { > /* Allocate a buffer where we construct the new block. */ > @@ -1299,6 +1737,24 @@ ext4_xattr_block_set(handle_t *handle, struct inode *inode, > goto bad_block; > if (error) > goto cleanup; > + > + if (i->value && s->here->e_value_inum) { > + unsigned int ea_ino; > + > + /* > + * A ref count on ea_inode has been taken as part of the call to > + * ext4_xattr_set_entry() above. We would like to drop this > + * extra ref but we have to wait until the xattr block is > + * initialized and has its own ref count on the ea_inode. > + */ > + ea_ino = le32_to_cpu(s->here->e_value_inum); > + error = ext4_xattr_inode_iget(inode, ea_ino, &ea_inode); > + if (error) { > + ea_inode = NULL; > + goto cleanup; > + } > + } > + > if (!IS_LAST_ENTRY(s->first)) > ext4_xattr_rehash(header(s->base), s->here); > > @@ -1409,6 +1865,22 @@ ext4_xattr_block_set(handle_t *handle, struct inode *inode, > EXT4_FREE_BLOCKS_METADATA); > goto cleanup; > } > + error = ext4_xattr_inode_inc_ref_all(handle, inode, > + ENTRY(header(s->base)+1)); > + if (error) > + goto getblk_failed; > + if (ea_inode) { > + /* Drop the extra ref on ea_inode. */ > + error = ext4_xattr_inode_dec_ref(handle, > + ea_inode); > + if (error) > + ext4_warning_inode(ea_inode, > + "dec ref error=%d", > + error); > + iput(ea_inode); > + ea_inode = NULL; > + } > + > lock_buffer(new_bh); > error = ext4_journal_get_create_access(handle, new_bh); > if (error) { > @@ -1428,15 +1900,38 @@ ext4_xattr_block_set(handle_t *handle, struct inode *inode, > } > } > > + if (old_ea_inode_size) > + ext4_xattr_inode_free_quota(inode, old_ea_inode_size); > + > /* Update the inode. */ > EXT4_I(inode)->i_file_acl = new_bh ? new_bh->b_blocknr : 0; > > /* Drop the previous xattr block. */ > - if (bs->bh && bs->bh != new_bh) > - ext4_xattr_release_block(handle, inode, bs->bh); > + if (bs->bh && bs->bh != new_bh) { > + struct ext4_xattr_inode_array *ea_inode_array = NULL; > + > + ext4_xattr_release_block(handle, inode, bs->bh, > + &ea_inode_array, > + 0 /* extra_credits */); > + ext4_xattr_inode_array_free(ea_inode_array); > + } > error = 0; > > cleanup: > + if (ea_inode) { > + int error2; > + > + error2 = ext4_xattr_inode_dec_ref(handle, ea_inode); > + if (error2) > + ext4_warning_inode(ea_inode, "dec ref error=%d", > + error2); > + > + /* If there was an error, revert the quota charge. */ > + if (error) > + ext4_xattr_inode_free_quota(inode, > + i_size_read(ea_inode)); > + iput(ea_inode); > + } > if (ce) > mb_cache_entry_put(ext4_mb_cache, ce); > brelse(new_bh); > @@ -1561,6 +2056,22 @@ static int ext4_xattr_value_same(struct ext4_xattr_search *s, > return !memcmp(value, i->value, i->value_len); > } > > +static struct buffer_head *ext4_xattr_get_block(struct inode *inode) > +{ > + struct buffer_head *bh; > + int error; > + > + if (!EXT4_I(inode)->i_file_acl) > + return NULL; > + bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); > + if (!bh) > + return ERR_PTR(-EIO); > + error = ext4_xattr_check_block(inode, bh); > + if (error) > + return ERR_PTR(error); > + return bh; > +} > + > /* > * ext4_xattr_set_handle() > * > @@ -1603,9 +2114,18 @@ ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index, > > /* Check journal credits under write lock. */ > if (ext4_handle_valid(handle)) { > + struct buffer_head *bh; > int credits; > > - credits = ext4_xattr_set_credits(inode, value_len); > + bh = ext4_xattr_get_block(inode); > + if (IS_ERR(bh)) { > + error = PTR_ERR(bh); > + goto cleanup; > + } > + > + credits = __ext4_xattr_set_credits(inode->i_sb, bh, value_len); > + brelse(bh); > + > if (!ext4_handle_has_enough_credits(handle, credits)) { > error = -ENOSPC; > goto cleanup; > @@ -1641,6 +2161,7 @@ ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index, > if (flags & XATTR_CREATE) > goto cleanup; > } > + > if (!value) { > if (!is.s.not_found) > error = ext4_xattr_ibody_set(handle, inode, &i, &is); > @@ -1709,34 +2230,29 @@ ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index, > return error; > } > > -int ext4_xattr_set_credits(struct inode *inode, size_t value_len) > +int ext4_xattr_set_credits(struct inode *inode, size_t value_len, int *credits) > { > - struct super_block *sb = inode->i_sb; > - int credits; > - > - if (!EXT4_SB(sb)->s_journal) > - return 0; > + struct buffer_head *bh; > + int err; > > - credits = EXT4_DATA_TRANS_BLOCKS(inode->i_sb); > + *credits = 0; > > - /* > - * In case of inline data, we may push out the data to a block, > - * so we need to reserve credits for this eventuality > - */ > - if (ext4_has_inline_data(inode)) > - credits += ext4_writepage_trans_blocks(inode) + 1; > - > - if (ext4_has_feature_ea_inode(sb)) { > - int nrblocks = (value_len + sb->s_blocksize - 1) >> > - sb->s_blocksize_bits; > + if (!EXT4_SB(inode->i_sb)->s_journal) > + return 0; > > - /* For new inode */ > - credits += EXT4_SINGLEDATA_TRANS_BLOCKS(sb) + 3; > + down_read(&EXT4_I(inode)->xattr_sem); > > - /* For data blocks of EA inode */ > - credits += ext4_meta_trans_blocks(inode, nrblocks, 0); > + bh = ext4_xattr_get_block(inode); > + if (IS_ERR(bh)) { > + err = PTR_ERR(bh); > + } else { > + *credits = __ext4_xattr_set_credits(inode->i_sb, bh, value_len); > + brelse(bh); > + err = 0; > } > - return credits; > + > + up_read(&EXT4_I(inode)->xattr_sem); > + return err; > } > > /* > @@ -1761,7 +2277,10 @@ ext4_xattr_set(struct inode *inode, int name_index, const char *name, > return error; > > retry: > - credits = ext4_xattr_set_credits(inode, value_len); > + error = ext4_xattr_set_credits(inode, value_len, &credits); > + if (error) > + return error; > + > handle = ext4_journal_start(inode, EXT4_HT_XATTR, credits); > if (IS_ERR(handle)) { > error = PTR_ERR(handle); > @@ -2067,10 +2586,10 @@ int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize, > return error; > } > > - > #define EIA_INCR 16 /* must be 2^n */ > #define EIA_MASK (EIA_INCR - 1) > -/* Add the large xattr @inode into @ea_inode_array for later deletion. > + > +/* Add the large xattr @inode into @ea_inode_array for deferred iput(). > * If @ea_inode_array is new or full it will be grown and the old > * contents copied over. > */ > @@ -2115,21 +2634,19 @@ ext4_expand_inode_array(struct ext4_xattr_inode_array **ea_inode_array, > * ext4_xattr_delete_inode() > * > * Free extended attribute resources associated with this inode. Traverse > - * all entries and unlink any xattr inodes associated with this inode. This > - * is called immediately before an inode is freed. We have exclusive > - * access to the inode. If an orphan inode is deleted it will also delete any > - * xattr block and all xattr inodes. They are checked by ext4_xattr_inode_iget() > - * to ensure they belong to the parent inode and were not deleted already. > + * all entries and decrement reference on any xattr inodes associated with this > + * inode. This is called immediately before an inode is freed. We have exclusive > + * access to the inode. If an orphan inode is deleted it will also release its > + * references on xattr block and xattr inodes. > */ > -int > -ext4_xattr_delete_inode(handle_t *handle, struct inode *inode, > - struct ext4_xattr_inode_array **ea_inode_array, > - int extra_credits) > +int ext4_xattr_delete_inode(handle_t *handle, struct inode *inode, > + struct ext4_xattr_inode_array **ea_inode_array, > + int extra_credits) > { > struct buffer_head *bh = NULL; > struct ext4_xattr_ibody_header *header; > - struct ext4_inode *raw_inode; > struct ext4_iloc iloc = { .bh = NULL }; > + struct ext4_xattr_entry *entry; > int error; > > error = ext4_xattr_ensure_credits(handle, inode, extra_credits, > @@ -2141,66 +2658,71 @@ ext4_xattr_delete_inode(handle_t *handle, struct inode *inode, > goto cleanup; > } > > - if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR)) > - goto delete_external_ea; > + if (ext4_has_feature_ea_inode(inode->i_sb) && > + ext4_test_inode_state(inode, EXT4_STATE_XATTR)) { > > - error = ext4_get_inode_loc(inode, &iloc); > - if (error) > - goto cleanup; > - > - error = ext4_journal_get_write_access(handle, iloc.bh); > - if (error) > - goto cleanup; > + error = ext4_get_inode_loc(inode, &iloc); > + if (error) { > + EXT4_ERROR_INODE(inode, "inode loc (error %d)", error); > + goto cleanup; > + } > > - raw_inode = ext4_raw_inode(&iloc); > - header = IHDR(inode, raw_inode); > - ext4_xattr_inode_remove_all(handle, inode, iloc.bh, IFIRST(header), > - false /* block_csum */, ea_inode_array, > - extra_credits); > + error = ext4_journal_get_write_access(handle, iloc.bh); > + if (error) { > + EXT4_ERROR_INODE(inode, "write access (error %d)", > + error); > + goto cleanup; > + } > > -delete_external_ea: > - if (!EXT4_I(inode)->i_file_acl) { > - error = 0; > - goto cleanup; > - } > - bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); > - if (!bh) { > - EXT4_ERROR_INODE(inode, "block %llu read error", > - EXT4_I(inode)->i_file_acl); > - error = -EIO; > - goto cleanup; > - } > - if (BHDR(bh)->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC) || > - BHDR(bh)->h_blocks != cpu_to_le32(1)) { > - EXT4_ERROR_INODE(inode, "bad block %llu", > - EXT4_I(inode)->i_file_acl); > - error = -EFSCORRUPTED; > - goto cleanup; > + header = IHDR(inode, ext4_raw_inode(&iloc)); > + if (header->h_magic == cpu_to_le32(EXT4_XATTR_MAGIC)) > + ext4_xattr_inode_dec_ref_all(handle, inode, iloc.bh, > + IFIRST(header), > + false /* block_csum */, > + ea_inode_array, > + extra_credits, > + false /* skip_quota */); > } > > - if (ext4_has_feature_ea_inode(inode->i_sb)) { > - error = ext4_journal_get_write_access(handle, bh); > - if (error) { > - EXT4_ERROR_INODE(inode, "write access %llu", > + if (EXT4_I(inode)->i_file_acl) { > + bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); > + if (!bh) { > + EXT4_ERROR_INODE(inode, "block %llu read error", > EXT4_I(inode)->i_file_acl); > + error = -EIO; > + goto cleanup; > + } > + error = ext4_xattr_check_block(inode, bh); > + if (error) { > + EXT4_ERROR_INODE(inode, "bad block %llu (error %d)", > + EXT4_I(inode)->i_file_acl, error); > goto cleanup; > } > - ext4_xattr_inode_remove_all(handle, inode, bh, > - BFIRST(bh), > - true /* block_csum */, > - ea_inode_array, > - extra_credits); > - } > > - ext4_xattr_release_block(handle, inode, bh); > - /* Update i_file_acl within the same transaction that releases block. */ > - EXT4_I(inode)->i_file_acl = 0; > - error = ext4_mark_inode_dirty(handle, inode); > - if (error) { > - EXT4_ERROR_INODE(inode, "mark inode dirty (error %d)", > - error); > - goto cleanup; > + if (ext4_has_feature_ea_inode(inode->i_sb)) { > + for (entry = BFIRST(bh); !IS_LAST_ENTRY(entry); > + entry = EXT4_XATTR_NEXT(entry)) > + if (entry->e_value_inum) > + ext4_xattr_inode_free_quota(inode, > + le32_to_cpu(entry->e_value_size)); > + > + } > + > + ext4_xattr_release_block(handle, inode, bh, ea_inode_array, > + extra_credits); > + /* > + * Update i_file_acl value in the same transaction that releases > + * block. > + */ > + EXT4_I(inode)->i_file_acl = 0; > + error = ext4_mark_inode_dirty(handle, inode); > + if (error) { > + EXT4_ERROR_INODE(inode, "mark inode dirty (error %d)", > + error); > + goto cleanup; > + } > } > + error = 0; > cleanup: > brelse(iloc.bh); > brelse(bh); > @@ -2209,17 +2731,13 @@ ext4_xattr_delete_inode(handle_t *handle, struct inode *inode, > > void ext4_xattr_inode_array_free(struct ext4_xattr_inode_array *ea_inode_array) > { > - struct inode *ea_inode; > - int idx = 0; > + int idx; > > if (ea_inode_array == NULL) > return; > > - for (; idx < ea_inode_array->count; ++idx) { > - ea_inode = ea_inode_array->inodes[idx]; > - clear_nlink(ea_inode); > - iput(ea_inode); > - } > + for (idx = 0; idx < ea_inode_array->count; ++idx) > + iput(ea_inode_array->inodes[idx]); > kfree(ea_inode_array); > } > > diff --git a/fs/ext4/xattr.h b/fs/ext4/xattr.h > index b2005a2716d9..67616cb9a059 100644 > --- a/fs/ext4/xattr.h > +++ b/fs/ext4/xattr.h > @@ -69,19 +69,6 @@ struct ext4_xattr_entry { > EXT4_I(inode)->i_extra_isize)) > #define IFIRST(hdr) ((struct ext4_xattr_entry *)((hdr)+1)) > > -/* > - * Link EA inode back to parent one using i_mtime field. > - * Extra integer type conversion added to ignore higher > - * bits in i_mtime.tv_sec which might be set by ext4_get() > - */ > -#define EXT4_XATTR_INODE_SET_PARENT(inode, inum) \ > -do { \ > - (inode)->i_mtime.tv_sec = inum; \ > -} while(0) > - > -#define EXT4_XATTR_INODE_GET_PARENT(inode) \ > -((__u32)(inode)->i_mtime.tv_sec) > - > /* > * The minimum size of EA value when you start storing it in an external inode > * size of block - size of header - size of 1 entry - 4 null bytes > @@ -165,9 +152,9 @@ extern ssize_t ext4_listxattr(struct dentry *, char *, size_t); > extern int ext4_xattr_get(struct inode *, int, const char *, void *, size_t); > extern int ext4_xattr_set(struct inode *, int, const char *, const void *, size_t, int); > extern int ext4_xattr_set_handle(handle_t *, struct inode *, int, const char *, const void *, size_t, int); > -extern int ext4_xattr_set_credits(struct inode *inode, size_t value_len); > +extern int ext4_xattr_set_credits(struct inode *inode, size_t value_len, > + int *credits); > > -extern int ext4_xattr_inode_unlink(struct inode *inode, unsigned long ea_ino); > extern int ext4_xattr_delete_inode(handle_t *handle, struct inode *inode, > struct ext4_xattr_inode_array **array, > int extra_credits); > diff --git a/fs/mbcache.c b/fs/mbcache.c > index 45a8d52dc991..d818fd236787 100644 > --- a/fs/mbcache.c > +++ b/fs/mbcache.c > @@ -13,10 +13,11 @@ > * mb_cache_entry_delete()). > * > * Ext2 and ext4 use this cache for deduplication of extended attribute blocks. > - * They use hash of a block contents as a key and block number as a value. > - * That's why keys need not be unique (different xattr blocks may end up having > - * the same hash). However block number always uniquely identifies a cache > - * entry. > + * Ext4 also uses it for deduplication of xattr values stored in inodes. > + * They use hash of data as a key and provide a value that may represent a > + * block or inode number. That's why keys need not be unique (hash of different > + * data may be the same). However user provided value always uniquely > + * identifies a cache entry. > * > * We provide functions for creation and removal of entries, search by key, > * and a special "delete entry with given key-value pair" operation. Fixed > -- > 2.13.1.518.g3df882009-goog >