diff options
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/ext4/inode.c | 63 | ||||
| -rw-r--r-- | fs/ext4/xattr.c | 274 | ||||
| -rw-r--r-- | fs/ext4/xattr.h | 17 |
3 files changed, 346 insertions, 8 deletions
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index b83f91edebd..f6d8528c4f5 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -3106,6 +3106,39 @@ ext4_reserve_inode_write(handle_t *handle, struct inode *inode, } /* + * Expand an inode by new_extra_isize bytes. + * Returns 0 on success or negative error number on failure. + */ +int ext4_expand_extra_isize(struct inode *inode, unsigned int new_extra_isize, + struct ext4_iloc iloc, handle_t *handle) +{ + struct ext4_inode *raw_inode; + struct ext4_xattr_ibody_header *header; + struct ext4_xattr_entry *entry; + + if (EXT4_I(inode)->i_extra_isize >= new_extra_isize) + return 0; + + raw_inode = ext4_raw_inode(&iloc); + + header = IHDR(inode, raw_inode); + entry = IFIRST(header); + + /* No extended attributes present */ + if (!(EXT4_I(inode)->i_state & EXT4_STATE_XATTR) || + header->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC)) { + memset((void *)raw_inode + EXT4_GOOD_OLD_INODE_SIZE, 0, + new_extra_isize); + EXT4_I(inode)->i_extra_isize = new_extra_isize; + return 0; + } + + /* try to expand with EAs present */ + return ext4_expand_extra_isize_ea(inode, new_extra_isize, + raw_inode, handle); +} + +/* * What we do here is to mark the in-core inode as clean with respect to inode * dirtiness (it may still be data-dirty). * This means that the in-core inode may be reaped by prune_icache @@ -3129,10 +3162,38 @@ ext4_reserve_inode_write(handle_t *handle, struct inode *inode, int ext4_mark_inode_dirty(handle_t *handle, struct inode *inode) { struct ext4_iloc iloc; - int err; + struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); + static unsigned int mnt_count; + int err, ret; might_sleep(); err = ext4_reserve_inode_write(handle, inode, &iloc); + if (EXT4_I(inode)->i_extra_isize < sbi->s_want_extra_isize && + !(EXT4_I(inode)->i_state & EXT4_STATE_NO_EXPAND)) { + /* + * We need extra buffer credits since we may write into EA block + * with this same handle. If journal_extend fails, then it will + * only result in a minor loss of functionality for that inode. + * If this is felt to be critical, then e2fsck should be run to + * force a large enough s_min_extra_isize. + */ + if ((jbd2_journal_extend(handle, + EXT4_DATA_TRANS_BLOCKS(inode->i_sb))) == 0) { + ret = ext4_expand_extra_isize(inode, + sbi->s_want_extra_isize, + iloc, handle); + if (ret) { + EXT4_I(inode)->i_state |= EXT4_STATE_NO_EXPAND; + if (mnt_count != sbi->s_es->s_mnt_count) { + ext4_warning(inode->i_sb, __FUNCTION__, + "Unable to expand inode %lu. Delete" + " some EAs or run e2fsck.", + inode->i_ino); + mnt_count = sbi->s_es->s_mnt_count; + } + } + } + } if (!err) err = ext4_mark_iloc_dirty(handle, inode, &iloc); return err; diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c index fe16a569d06..b10d68fffb5 100644 --- a/fs/ext4/xattr.c +++ b/fs/ext4/xattr.c @@ -66,13 +66,6 @@ #define BFIRST(bh) ENTRY(BHDR(bh)+1) #define IS_LAST_ENTRY(entry) (*(__u32 *)(entry) == 0) -#define IHDR(inode, raw_inode) \ - ((struct ext4_xattr_ibody_header *) \ - ((void *)raw_inode + \ - EXT4_GOOD_OLD_INODE_SIZE + \ - EXT4_I(inode)->i_extra_isize)) -#define IFIRST(hdr) ((struct ext4_xattr_entry *)((hdr)+1)) - #ifdef EXT4_XATTR_DEBUG # define ea_idebug(inode, f...) do { \ printk(KERN_DEBUG "inode %s:%lu: ", \ @@ -508,6 +501,24 @@ out: return; } +/* + * Find the available free space for EAs. This also returns the total number of + * bytes used by EA entries. + */ +static size_t ext4_xattr_free_space(struct ext4_xattr_entry *last, + size_t *min_offs, void *base, int *total) +{ + for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { + *total += EXT4_XATTR_LEN(last->e_name_len); + if (!last->e_value_block && last->e_value_size) { + size_t offs = le16_to_cpu(last->e_value_offs); + if (offs < *min_offs) + *min_offs = offs; + } + } + return (*min_offs - ((void *)last - base) - sizeof(__u32)); +} + struct ext4_xattr_info { int name_index; const char *name; @@ -1014,6 +1025,8 @@ ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index, if (!error) { ext4_xattr_update_super_block(handle, inode->i_sb); inode->i_ctime = ext4_current_time(inode); + if (!value) + EXT4_I(inode)->i_state &= ~EXT4_STATE_NO_EXPAND; error = ext4_mark_iloc_dirty(handle, inode, &is.iloc); /* * The bh is consumed by ext4_mark_iloc_dirty, even with @@ -1067,6 +1080,253 @@ retry: } /* + * Shift the EA entries in the inode to create space for the increased + * i_extra_isize. + */ +static void ext4_xattr_shift_entries(struct ext4_xattr_entry *entry, + int value_offs_shift, void *to, + void *from, size_t n, int blocksize) +{ + struct ext4_xattr_entry *last = entry; + int new_offs; + + /* Adjust the value offsets of the entries */ + for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { + if (!last->e_value_block && last->e_value_size) { + new_offs = le16_to_cpu(last->e_value_offs) + + value_offs_shift; + BUG_ON(new_offs + le32_to_cpu(last->e_value_size) + > blocksize); + last->e_value_offs = cpu_to_le16(new_offs); + } + } + /* Shift the entries by n bytes */ + memmove(to, from, n); +} + +/* + * Expand an inode by new_extra_isize bytes when EAs are present. + * Returns 0 on success or negative error number on failure. + */ +int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize, + struct ext4_inode *raw_inode, handle_t *handle) +{ + struct ext4_xattr_ibody_header *header; + struct ext4_xattr_entry *entry, *last, *first; + struct buffer_head *bh = NULL; + struct ext4_xattr_ibody_find *is = NULL; + struct ext4_xattr_block_find *bs = NULL; + char *buffer = NULL, *b_entry_name = NULL; + size_t min_offs, free; + int total_ino, total_blk; + void *base, *start, *end; + int extra_isize = 0, error = 0, tried_min_extra_isize = 0; + int s_min_extra_isize = EXT4_SB(inode->i_sb)->s_es->s_min_extra_isize; + + down_write(&EXT4_I(inode)->xattr_sem); +retry: + if (EXT4_I(inode)->i_extra_isize >= new_extra_isize) { + up_write(&EXT4_I(inode)->xattr_sem); + return 0; + } + + header = IHDR(inode, raw_inode); + entry = IFIRST(header); + + /* + * Check if enough free space is available in the inode to shift the + * entries ahead by new_extra_isize. + */ + + base = start = entry; + end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; + min_offs = end - base; + last = entry; + total_ino = sizeof(struct ext4_xattr_ibody_header); + + free = ext4_xattr_free_space(last, &min_offs, base, &total_ino); + if (free >= new_extra_isize) { + entry = IFIRST(header); + ext4_xattr_shift_entries(entry, EXT4_I(inode)->i_extra_isize + - new_extra_isize, (void *)raw_inode + + EXT4_GOOD_OLD_INODE_SIZE + new_extra_isize, + (void *)header, total_ino, + inode->i_sb->s_blocksize); + EXT4_I(inode)->i_extra_isize = new_extra_isize; + error = 0; + goto cleanup; + } + + /* + * Enough free space isn't available in the inode, check if + * EA block can hold new_extra_isize bytes. + */ + if (EXT4_I(inode)->i_file_acl) { + bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); + error = -EIO; + if (!bh) + goto cleanup; + if (ext4_xattr_check_block(bh)) { + ext4_error(inode->i_sb, __FUNCTION__, + "inode %lu: bad block %llu", inode->i_ino, + EXT4_I(inode)->i_file_acl); + error = -EIO; + goto cleanup; + } + base = BHDR(bh); + first = BFIRST(bh); + end = bh->b_data + bh->b_size; + min_offs = end - base; + free = ext4_xattr_free_space(first, &min_offs, base, + &total_blk); + if (free < new_extra_isize) { + if (!tried_min_extra_isize && s_min_extra_isize) { + tried_min_extra_isize++; + new_extra_isize = s_min_extra_isize; + brelse(bh); + goto retry; + } + error = -1; + goto cleanup; + } + } else { + free = inode->i_sb->s_blocksize; + } + + while (new_extra_isize > 0) { + size_t offs, size, entry_size; + struct ext4_xattr_entry *small_entry = NULL; + struct ext4_xattr_info i = { + .value = NULL, + .value_len = 0, + }; + unsigned int total_size; /* EA entry size + value size */ + unsigned int shift_bytes; /* No. of bytes to shift EAs by? */ + unsigned int min_total_size = ~0U; + + is = kzalloc(sizeof(struct ext4_xattr_ibody_find), GFP_NOFS); + bs = kzalloc(sizeof(struct ext4_xattr_block_find), GFP_NOFS); + if (!is || !bs) { + error = -ENOMEM; + goto cleanup; + } + + is->s.not_found = -ENODATA; + bs->s.not_found = -ENODATA; + is->iloc.bh = NULL; + bs->bh = NULL; + + last = IFIRST(header); + /* Find the entry best suited to be pushed into EA block */ + entry = NULL; + for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { + total_size = + EXT4_XATTR_SIZE(le32_to_cpu(last->e_value_size)) + + EXT4_XATTR_LEN(last->e_name_len); + if (total_size <= free && total_size < min_total_size) { + if (total_size < new_extra_isize) { + small_entry = last; + } else { + entry = last; + min_total_size = total_size; + } + } + } + + if (entry == NULL) { + if (small_entry) { + entry = small_entry; + } else { + if (!tried_min_extra_isize && + s_min_extra_isize) { + tried_min_extra_isize++; + new_extra_isize = s_min_extra_isize; + goto retry; + } + error = -1; + goto cleanup; + } + } + offs = le16_to_cpu(entry->e_value_offs); + size = le32_to_cpu(entry->e_value_size); + entry_size = EXT4_XATTR_LEN(entry->e_name_len); + i.name_index = entry->e_name_index, + buffer = kmalloc(EXT4_XATTR_SIZE(size), GFP_NOFS); + b_entry_name = kmalloc(entry->e_name_len + 1, GFP_NOFS); + if (!buffer || !b_entry_name) { + error = -ENOMEM; + goto cleanup; + } + /* Save the entry name and the entry value */ + memcpy(buffer, (void *)IFIRST(header) + offs, + EXT4_XATTR_SIZE(size)); + memcpy(b_entry_name, entry->e_name, entry->e_name_len); + b_entry_name[entry->e_name_len] = '\0'; + i.name = b_entry_name; + + error = ext4_get_inode_loc(inode, &is->iloc); + if (error) + goto cleanup; + + error = ext4_xattr_ibody_find(inode, &i, is); + if (error) + goto cleanup; + + /* Remove the chosen entry from the inode */ + error = ext4_xattr_ibody_set(handle, inode, &i, is); + + entry = IFIRST(header); + if (entry_size + EXT4_XATTR_SIZE(size) >= new_extra_isize) + shift_bytes = new_extra_isize; + else + shift_bytes = entry_size + size; + /* Adjust the offsets and shift the remaining entries ahead */ + ext4_xattr_shift_entries(entry, EXT4_I(inode)->i_extra_isize - + shift_bytes, (void *)raw_inode + + EXT4_GOOD_OLD_INODE_SIZE + extra_isize + shift_bytes, + (void *)header, total_ino - entry_size, + inode->i_sb->s_blocksize); + + extra_isize += shift_bytes; + new_extra_isize -= shift_bytes; + EXT4_I(inode)->i_extra_isize = extra_isize; + + i.name = b_entry_name; + i.value = buffer; + i.value_len = cpu_to_le32(size); + error = ext4_xattr_block_find(inode, &i, bs); + if (error) + goto cleanup; + + /* Add entry which was removed from the inode into the block */ + error = ext4_xattr_block_set(handle, inode, &i, bs); + if (error) + goto cleanup; + kfree(b_entry_name); + kfree(buffer); + brelse(is->iloc.bh); + kfree(is); + kfree(bs); + } + brelse(bh); + up_write(&EXT4_I(inode)->xattr_sem); + return 0; + +cleanup: + kfree(b_entry_name); + kfree(buffer); + if (is) + brelse(is->iloc.bh); + kfree(is); + kfree(bs); + brelse(bh); + up_write(&EXT4_I(inode)->xattr_sem); + return error; +} + + + +/* * ext4_xattr_delete_inode() * * Free extended attribute resources associated with this inode. This diff --git a/fs/ext4/xattr.h b/fs/ext4/xattr.h index 79432b35398..d7f5d6a1265 100644 --- a/fs/ext4/xattr.h +++ b/fs/ext4/xattr.h @@ -56,6 +56,13 @@ struct ext4_xattr_entry { #define EXT4_XATTR_SIZE(size) \ (((size) + EXT4_XATTR_ROUND) & ~EXT4_XATTR_ROUND) +#define IHDR(inode, raw_inode) \ + ((struct ext4_xattr_ibody_header *) \ + ((void *)raw_inode + \ + EXT4_GOOD_OLD_INODE_SIZE + \ + EXT4_I(inode)->i_extra_isize)) +#define IFIRST(hdr) ((struct ext4_xattr_entry *)((hdr)+1)) + # ifdef CONFIG_EXT4DEV_FS_XATTR extern struct xattr_handler ext4_xattr_user_handler; @@ -74,6 +81,9 @@ extern int ext4_xattr_set_handle(handle_t *, struct inode *, int, const char *, extern void ext4_xattr_delete_inode(handle_t *, struct inode *); extern void ext4_xattr_put_super(struct super_block *); +extern int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize, + struct ext4_inode *raw_inode, handle_t *handle); + extern int init_ext4_xattr(void); extern void exit_ext4_xattr(void); @@ -129,6 +139,13 @@ exit_ext4_xattr(void) { } +static inline int +ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize, + struct ext4_inode *raw_inode, handle_t *handle) +{ + return -EOPNOTSUPP; +} + #define ext4_xattr_handlers NULL # endif /* CONFIG_EXT4DEV_FS_XATTR */ |