1ac27a0ecSDave Kleikamp /* 2617ba13bSMingming Cao * linux/fs/ext4/xattr.c 3ac27a0ecSDave Kleikamp * 4ac27a0ecSDave Kleikamp * Copyright (C) 2001-2003 Andreas Gruenbacher, <agruen@suse.de> 5ac27a0ecSDave Kleikamp * 6ac27a0ecSDave Kleikamp * Fix by Harrison Xing <harrison@mountainviewdata.com>. 7617ba13bSMingming Cao * Ext4 code with a lot of help from Eric Jarman <ejarman@acm.org>. 8ac27a0ecSDave Kleikamp * Extended attributes for symlinks and special files added per 9ac27a0ecSDave Kleikamp * suggestion of Luka Renko <luka.renko@hermes.si>. 10ac27a0ecSDave Kleikamp * xattr consolidation Copyright (c) 2004 James Morris <jmorris@redhat.com>, 11ac27a0ecSDave Kleikamp * Red Hat Inc. 12ac27a0ecSDave Kleikamp * ea-in-inode support by Alex Tomas <alex@clusterfs.com> aka bzzz 13ac27a0ecSDave Kleikamp * and Andreas Gruenbacher <agruen@suse.de>. 14ac27a0ecSDave Kleikamp */ 15ac27a0ecSDave Kleikamp 16ac27a0ecSDave Kleikamp /* 17ac27a0ecSDave Kleikamp * Extended attributes are stored directly in inodes (on file systems with 18ac27a0ecSDave Kleikamp * inodes bigger than 128 bytes) and on additional disk blocks. The i_file_acl 19ac27a0ecSDave Kleikamp * field contains the block number if an inode uses an additional block. All 20ac27a0ecSDave Kleikamp * attributes must fit in the inode and one additional block. Blocks that 21ac27a0ecSDave Kleikamp * contain the identical set of attributes may be shared among several inodes. 22ac27a0ecSDave Kleikamp * Identical blocks are detected by keeping a cache of blocks that have 23ac27a0ecSDave Kleikamp * recently been accessed. 24ac27a0ecSDave Kleikamp * 25ac27a0ecSDave Kleikamp * The attributes in inodes and on blocks have a different header; the entries 26ac27a0ecSDave Kleikamp * are stored in the same format: 27ac27a0ecSDave Kleikamp * 28ac27a0ecSDave Kleikamp * +------------------+ 29ac27a0ecSDave Kleikamp * | header | 30ac27a0ecSDave Kleikamp * | entry 1 | | 31ac27a0ecSDave Kleikamp * | entry 2 | | growing downwards 32ac27a0ecSDave Kleikamp * | entry 3 | v 33ac27a0ecSDave Kleikamp * | four null bytes | 34ac27a0ecSDave Kleikamp * | . . . | 35ac27a0ecSDave Kleikamp * | value 1 | ^ 36ac27a0ecSDave Kleikamp * | value 3 | | growing upwards 37ac27a0ecSDave Kleikamp * | value 2 | | 38ac27a0ecSDave Kleikamp * +------------------+ 39ac27a0ecSDave Kleikamp * 40ac27a0ecSDave Kleikamp * The header is followed by multiple entry descriptors. In disk blocks, the 41ac27a0ecSDave Kleikamp * entry descriptors are kept sorted. In inodes, they are unsorted. The 42ac27a0ecSDave Kleikamp * attribute values are aligned to the end of the block in no specific order. 43ac27a0ecSDave Kleikamp * 44ac27a0ecSDave Kleikamp * Locking strategy 45ac27a0ecSDave Kleikamp * ---------------- 46617ba13bSMingming Cao * EXT4_I(inode)->i_file_acl is protected by EXT4_I(inode)->xattr_sem. 47ac27a0ecSDave Kleikamp * EA blocks are only changed if they are exclusive to an inode, so 48ac27a0ecSDave Kleikamp * holding xattr_sem also means that nothing but the EA block's reference 49ac27a0ecSDave Kleikamp * count can change. Multiple writers to the same block are synchronized 50ac27a0ecSDave Kleikamp * by the buffer lock. 51ac27a0ecSDave Kleikamp */ 52ac27a0ecSDave Kleikamp 53ac27a0ecSDave Kleikamp #include <linux/init.h> 54ac27a0ecSDave Kleikamp #include <linux/fs.h> 55ac27a0ecSDave Kleikamp #include <linux/slab.h> 567a2508e1SJan Kara #include <linux/mbcache.h> 57ac27a0ecSDave Kleikamp #include <linux/quotaops.h> 583dcf5451SChristoph Hellwig #include "ext4_jbd2.h" 593dcf5451SChristoph Hellwig #include "ext4.h" 60ac27a0ecSDave Kleikamp #include "xattr.h" 61ac27a0ecSDave Kleikamp #include "acl.h" 62ac27a0ecSDave Kleikamp 63617ba13bSMingming Cao #ifdef EXT4_XATTR_DEBUG 64ac27a0ecSDave Kleikamp # define ea_idebug(inode, f...) do { \ 65ac27a0ecSDave Kleikamp printk(KERN_DEBUG "inode %s:%lu: ", \ 66ac27a0ecSDave Kleikamp inode->i_sb->s_id, inode->i_ino); \ 67ac27a0ecSDave Kleikamp printk(f); \ 68ac27a0ecSDave Kleikamp printk("\n"); \ 69ac27a0ecSDave Kleikamp } while (0) 70ac27a0ecSDave Kleikamp # define ea_bdebug(bh, f...) do { \ 71a1c6f057SDmitry Monakhov printk(KERN_DEBUG "block %pg:%lu: ", \ 72a1c6f057SDmitry Monakhov bh->b_bdev, (unsigned long) bh->b_blocknr); \ 73ac27a0ecSDave Kleikamp printk(f); \ 74ac27a0ecSDave Kleikamp printk("\n"); \ 75ac27a0ecSDave Kleikamp } while (0) 76ac27a0ecSDave Kleikamp #else 77ace36ad4SJoe Perches # define ea_idebug(inode, fmt, ...) no_printk(fmt, ##__VA_ARGS__) 78ace36ad4SJoe Perches # define ea_bdebug(bh, fmt, ...) no_printk(fmt, ##__VA_ARGS__) 79ac27a0ecSDave Kleikamp #endif 80ac27a0ecSDave Kleikamp 817a2508e1SJan Kara static void ext4_xattr_cache_insert(struct mb_cache *, struct buffer_head *); 82617ba13bSMingming Cao static struct buffer_head *ext4_xattr_cache_find(struct inode *, 83617ba13bSMingming Cao struct ext4_xattr_header *, 847a2508e1SJan Kara struct mb_cache_entry **); 85617ba13bSMingming Cao static void ext4_xattr_rehash(struct ext4_xattr_header *, 86617ba13bSMingming Cao struct ext4_xattr_entry *); 87431547b3SChristoph Hellwig static int ext4_xattr_list(struct dentry *dentry, char *buffer, 88d3a95d47SMingming Cao size_t buffer_size); 89ac27a0ecSDave Kleikamp 9011e27528SStephen Hemminger static const struct xattr_handler *ext4_xattr_handler_map[] = { 91617ba13bSMingming Cao [EXT4_XATTR_INDEX_USER] = &ext4_xattr_user_handler, 9203010a33STheodore Ts'o #ifdef CONFIG_EXT4_FS_POSIX_ACL 9364e178a7SChristoph Hellwig [EXT4_XATTR_INDEX_POSIX_ACL_ACCESS] = &posix_acl_access_xattr_handler, 9464e178a7SChristoph Hellwig [EXT4_XATTR_INDEX_POSIX_ACL_DEFAULT] = &posix_acl_default_xattr_handler, 95ac27a0ecSDave Kleikamp #endif 96617ba13bSMingming Cao [EXT4_XATTR_INDEX_TRUSTED] = &ext4_xattr_trusted_handler, 9703010a33STheodore Ts'o #ifdef CONFIG_EXT4_FS_SECURITY 98617ba13bSMingming Cao [EXT4_XATTR_INDEX_SECURITY] = &ext4_xattr_security_handler, 99ac27a0ecSDave Kleikamp #endif 100ac27a0ecSDave Kleikamp }; 101ac27a0ecSDave Kleikamp 10211e27528SStephen Hemminger const struct xattr_handler *ext4_xattr_handlers[] = { 103617ba13bSMingming Cao &ext4_xattr_user_handler, 104617ba13bSMingming Cao &ext4_xattr_trusted_handler, 10503010a33STheodore Ts'o #ifdef CONFIG_EXT4_FS_POSIX_ACL 10664e178a7SChristoph Hellwig &posix_acl_access_xattr_handler, 10764e178a7SChristoph Hellwig &posix_acl_default_xattr_handler, 108ac27a0ecSDave Kleikamp #endif 10903010a33STheodore Ts'o #ifdef CONFIG_EXT4_FS_SECURITY 110617ba13bSMingming Cao &ext4_xattr_security_handler, 111ac27a0ecSDave Kleikamp #endif 112ac27a0ecSDave Kleikamp NULL 113ac27a0ecSDave Kleikamp }; 114ac27a0ecSDave Kleikamp 1159c191f70ST Makphaibulchoke #define EXT4_GET_MB_CACHE(inode) (((struct ext4_sb_info *) \ 1169c191f70ST Makphaibulchoke inode->i_sb->s_fs_info)->s_mb_cache) 1179c191f70ST Makphaibulchoke 118cc8e94fdSDarrick J. Wong static __le32 ext4_xattr_block_csum(struct inode *inode, 119cc8e94fdSDarrick J. Wong sector_t block_nr, 120cc8e94fdSDarrick J. Wong struct ext4_xattr_header *hdr) 121cc8e94fdSDarrick J. Wong { 122cc8e94fdSDarrick J. Wong struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); 123d6a77105STheodore Ts'o __u32 csum; 124d6a77105STheodore Ts'o __le64 dsk_block_nr = cpu_to_le64(block_nr); 125b47820edSDaeho Jeong __u32 dummy_csum = 0; 126b47820edSDaeho Jeong int offset = offsetof(struct ext4_xattr_header, h_checksum); 127cc8e94fdSDarrick J. Wong 128d6a77105STheodore Ts'o csum = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&dsk_block_nr, 129d6a77105STheodore Ts'o sizeof(dsk_block_nr)); 130b47820edSDaeho Jeong csum = ext4_chksum(sbi, csum, (__u8 *)hdr, offset); 131b47820edSDaeho Jeong csum = ext4_chksum(sbi, csum, (__u8 *)&dummy_csum, sizeof(dummy_csum)); 132b47820edSDaeho Jeong offset += sizeof(dummy_csum); 133b47820edSDaeho Jeong csum = ext4_chksum(sbi, csum, (__u8 *)hdr + offset, 134b47820edSDaeho Jeong EXT4_BLOCK_SIZE(inode->i_sb) - offset); 13541eb70ddSTao Ma 136cc8e94fdSDarrick J. Wong return cpu_to_le32(csum); 137cc8e94fdSDarrick J. Wong } 138cc8e94fdSDarrick J. Wong 139cc8e94fdSDarrick J. Wong static int ext4_xattr_block_csum_verify(struct inode *inode, 140cc8e94fdSDarrick J. Wong sector_t block_nr, 141cc8e94fdSDarrick J. Wong struct ext4_xattr_header *hdr) 142cc8e94fdSDarrick J. Wong { 1439aa5d32bSDmitry Monakhov if (ext4_has_metadata_csum(inode->i_sb) && 144cc8e94fdSDarrick J. Wong (hdr->h_checksum != ext4_xattr_block_csum(inode, block_nr, hdr))) 145cc8e94fdSDarrick J. Wong return 0; 146cc8e94fdSDarrick J. Wong return 1; 147cc8e94fdSDarrick J. Wong } 148cc8e94fdSDarrick J. Wong 149cc8e94fdSDarrick J. Wong static void ext4_xattr_block_csum_set(struct inode *inode, 150cc8e94fdSDarrick J. Wong sector_t block_nr, 151cc8e94fdSDarrick J. Wong struct ext4_xattr_header *hdr) 152cc8e94fdSDarrick J. Wong { 1539aa5d32bSDmitry Monakhov if (!ext4_has_metadata_csum(inode->i_sb)) 154cc8e94fdSDarrick J. Wong return; 155cc8e94fdSDarrick J. Wong 156cc8e94fdSDarrick J. Wong hdr->h_checksum = ext4_xattr_block_csum(inode, block_nr, hdr); 157cc8e94fdSDarrick J. Wong } 158cc8e94fdSDarrick J. Wong 159cc8e94fdSDarrick J. Wong static inline int ext4_handle_dirty_xattr_block(handle_t *handle, 160cc8e94fdSDarrick J. Wong struct inode *inode, 161cc8e94fdSDarrick J. Wong struct buffer_head *bh) 162cc8e94fdSDarrick J. Wong { 163cc8e94fdSDarrick J. Wong ext4_xattr_block_csum_set(inode, bh->b_blocknr, BHDR(bh)); 164cc8e94fdSDarrick J. Wong return ext4_handle_dirty_metadata(handle, inode, bh); 165cc8e94fdSDarrick J. Wong } 166cc8e94fdSDarrick J. Wong 16711e27528SStephen Hemminger static inline const struct xattr_handler * 168617ba13bSMingming Cao ext4_xattr_handler(int name_index) 169ac27a0ecSDave Kleikamp { 17011e27528SStephen Hemminger const struct xattr_handler *handler = NULL; 171ac27a0ecSDave Kleikamp 172617ba13bSMingming Cao if (name_index > 0 && name_index < ARRAY_SIZE(ext4_xattr_handler_map)) 173617ba13bSMingming Cao handler = ext4_xattr_handler_map[name_index]; 174ac27a0ecSDave Kleikamp return handler; 175ac27a0ecSDave Kleikamp } 176ac27a0ecSDave Kleikamp 177ac27a0ecSDave Kleikamp /* 178ac27a0ecSDave Kleikamp * Inode operation listxattr() 179ac27a0ecSDave Kleikamp * 1802b0143b5SDavid Howells * d_inode(dentry)->i_mutex: don't care 181ac27a0ecSDave Kleikamp */ 182ac27a0ecSDave Kleikamp ssize_t 183617ba13bSMingming Cao ext4_listxattr(struct dentry *dentry, char *buffer, size_t size) 184ac27a0ecSDave Kleikamp { 185431547b3SChristoph Hellwig return ext4_xattr_list(dentry, buffer, size); 186ac27a0ecSDave Kleikamp } 187ac27a0ecSDave Kleikamp 188ac27a0ecSDave Kleikamp static int 189a0626e75SDarrick J. Wong ext4_xattr_check_names(struct ext4_xattr_entry *entry, void *end, 190a0626e75SDarrick J. Wong void *value_start) 191ac27a0ecSDave Kleikamp { 192a0626e75SDarrick J. Wong struct ext4_xattr_entry *e = entry; 193a0626e75SDarrick J. Wong 194a0626e75SDarrick J. Wong while (!IS_LAST_ENTRY(e)) { 195a0626e75SDarrick J. Wong struct ext4_xattr_entry *next = EXT4_XATTR_NEXT(e); 196ac27a0ecSDave Kleikamp if ((void *)next >= end) 1976a797d27SDarrick J. Wong return -EFSCORRUPTED; 198a0626e75SDarrick J. Wong e = next; 199ac27a0ecSDave Kleikamp } 200a0626e75SDarrick J. Wong 201a0626e75SDarrick J. Wong while (!IS_LAST_ENTRY(entry)) { 2022de58f11SJan Kara if (entry->e_value_block != 0) 2032de58f11SJan Kara return -EFSCORRUPTED; 204a0626e75SDarrick J. Wong if (entry->e_value_size != 0 && 205a0626e75SDarrick J. Wong (value_start + le16_to_cpu(entry->e_value_offs) < 206a0626e75SDarrick J. Wong (void *)e + sizeof(__u32) || 207a0626e75SDarrick J. Wong value_start + le16_to_cpu(entry->e_value_offs) + 208a0626e75SDarrick J. Wong le32_to_cpu(entry->e_value_size) > end)) 2096a797d27SDarrick J. Wong return -EFSCORRUPTED; 210a0626e75SDarrick J. Wong entry = EXT4_XATTR_NEXT(entry); 211a0626e75SDarrick J. Wong } 212a0626e75SDarrick J. Wong 213ac27a0ecSDave Kleikamp return 0; 214ac27a0ecSDave Kleikamp } 215ac27a0ecSDave Kleikamp 216ac27a0ecSDave Kleikamp static inline int 217cc8e94fdSDarrick J. Wong ext4_xattr_check_block(struct inode *inode, struct buffer_head *bh) 218ac27a0ecSDave Kleikamp { 219cc8e94fdSDarrick J. Wong int error; 220cc8e94fdSDarrick J. Wong 221cc8e94fdSDarrick J. Wong if (buffer_verified(bh)) 222cc8e94fdSDarrick J. Wong return 0; 223cc8e94fdSDarrick J. Wong 224617ba13bSMingming Cao if (BHDR(bh)->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC) || 225ac27a0ecSDave Kleikamp BHDR(bh)->h_blocks != cpu_to_le32(1)) 2266a797d27SDarrick J. Wong return -EFSCORRUPTED; 227cc8e94fdSDarrick J. Wong if (!ext4_xattr_block_csum_verify(inode, bh->b_blocknr, BHDR(bh))) 2286a797d27SDarrick J. Wong return -EFSBADCRC; 229a0626e75SDarrick J. Wong error = ext4_xattr_check_names(BFIRST(bh), bh->b_data + bh->b_size, 230a0626e75SDarrick J. Wong bh->b_data); 231cc8e94fdSDarrick J. Wong if (!error) 232cc8e94fdSDarrick J. Wong set_buffer_verified(bh); 233cc8e94fdSDarrick J. Wong return error; 234ac27a0ecSDave Kleikamp } 235ac27a0ecSDave Kleikamp 2369e92f48cSTheodore Ts'o static int 2379e92f48cSTheodore Ts'o __xattr_check_inode(struct inode *inode, struct ext4_xattr_ibody_header *header, 2389e92f48cSTheodore Ts'o void *end, const char *function, unsigned int line) 2399e92f48cSTheodore Ts'o { 2409e92f48cSTheodore Ts'o struct ext4_xattr_entry *entry = IFIRST(header); 2419e92f48cSTheodore Ts'o int error = -EFSCORRUPTED; 2429e92f48cSTheodore Ts'o 2439e92f48cSTheodore Ts'o if (((void *) header >= end) || 244*19962509SEric Biggers (header->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC))) 2459e92f48cSTheodore Ts'o goto errout; 2469e92f48cSTheodore Ts'o error = ext4_xattr_check_names(entry, end, entry); 2479e92f48cSTheodore Ts'o errout: 2489e92f48cSTheodore Ts'o if (error) 2499e92f48cSTheodore Ts'o __ext4_error_inode(inode, function, line, 0, 2509e92f48cSTheodore Ts'o "corrupted in-inode xattr"); 2519e92f48cSTheodore Ts'o return error; 2529e92f48cSTheodore Ts'o } 2539e92f48cSTheodore Ts'o 2549e92f48cSTheodore Ts'o #define xattr_check_inode(inode, header, end) \ 2559e92f48cSTheodore Ts'o __xattr_check_inode((inode), (header), (end), __func__, __LINE__) 2569e92f48cSTheodore Ts'o 257ac27a0ecSDave Kleikamp static inline int 258617ba13bSMingming Cao ext4_xattr_check_entry(struct ext4_xattr_entry *entry, size_t size) 259ac27a0ecSDave Kleikamp { 260ac27a0ecSDave Kleikamp size_t value_size = le32_to_cpu(entry->e_value_size); 261ac27a0ecSDave Kleikamp 262ac27a0ecSDave Kleikamp if (entry->e_value_block != 0 || value_size > size || 263ac27a0ecSDave Kleikamp le16_to_cpu(entry->e_value_offs) + value_size > size) 2646a797d27SDarrick J. Wong return -EFSCORRUPTED; 265ac27a0ecSDave Kleikamp return 0; 266ac27a0ecSDave Kleikamp } 267ac27a0ecSDave Kleikamp 268ac27a0ecSDave Kleikamp static int 269617ba13bSMingming Cao ext4_xattr_find_entry(struct ext4_xattr_entry **pentry, int name_index, 270ac27a0ecSDave Kleikamp const char *name, size_t size, int sorted) 271ac27a0ecSDave Kleikamp { 272617ba13bSMingming Cao struct ext4_xattr_entry *entry; 273ac27a0ecSDave Kleikamp size_t name_len; 274ac27a0ecSDave Kleikamp int cmp = 1; 275ac27a0ecSDave Kleikamp 276ac27a0ecSDave Kleikamp if (name == NULL) 277ac27a0ecSDave Kleikamp return -EINVAL; 278ac27a0ecSDave Kleikamp name_len = strlen(name); 279ac27a0ecSDave Kleikamp entry = *pentry; 280617ba13bSMingming Cao for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) { 281ac27a0ecSDave Kleikamp cmp = name_index - entry->e_name_index; 282ac27a0ecSDave Kleikamp if (!cmp) 283ac27a0ecSDave Kleikamp cmp = name_len - entry->e_name_len; 284ac27a0ecSDave Kleikamp if (!cmp) 285ac27a0ecSDave Kleikamp cmp = memcmp(name, entry->e_name, name_len); 286ac27a0ecSDave Kleikamp if (cmp <= 0 && (sorted || cmp == 0)) 287ac27a0ecSDave Kleikamp break; 288ac27a0ecSDave Kleikamp } 289ac27a0ecSDave Kleikamp *pentry = entry; 290617ba13bSMingming Cao if (!cmp && ext4_xattr_check_entry(entry, size)) 2916a797d27SDarrick J. Wong return -EFSCORRUPTED; 292ac27a0ecSDave Kleikamp return cmp ? -ENODATA : 0; 293ac27a0ecSDave Kleikamp } 294ac27a0ecSDave Kleikamp 295ac27a0ecSDave Kleikamp static int 296617ba13bSMingming Cao ext4_xattr_block_get(struct inode *inode, int name_index, const char *name, 297ac27a0ecSDave Kleikamp void *buffer, size_t buffer_size) 298ac27a0ecSDave Kleikamp { 299ac27a0ecSDave Kleikamp struct buffer_head *bh = NULL; 300617ba13bSMingming Cao struct ext4_xattr_entry *entry; 301ac27a0ecSDave Kleikamp size_t size; 302ac27a0ecSDave Kleikamp int error; 3037a2508e1SJan Kara struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); 304ac27a0ecSDave Kleikamp 305ac27a0ecSDave Kleikamp ea_idebug(inode, "name=%d.%s, buffer=%p, buffer_size=%ld", 306ac27a0ecSDave Kleikamp name_index, name, buffer, (long)buffer_size); 307ac27a0ecSDave Kleikamp 308ac27a0ecSDave Kleikamp error = -ENODATA; 309617ba13bSMingming Cao if (!EXT4_I(inode)->i_file_acl) 310ac27a0ecSDave Kleikamp goto cleanup; 311ace36ad4SJoe Perches ea_idebug(inode, "reading block %llu", 312ace36ad4SJoe Perches (unsigned long long)EXT4_I(inode)->i_file_acl); 313617ba13bSMingming Cao bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); 314ac27a0ecSDave Kleikamp if (!bh) 315ac27a0ecSDave Kleikamp goto cleanup; 316ac27a0ecSDave Kleikamp ea_bdebug(bh, "b_count=%d, refcount=%d", 317ac27a0ecSDave Kleikamp atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount)); 318cc8e94fdSDarrick J. Wong if (ext4_xattr_check_block(inode, bh)) { 31912062dddSEric Sandeen bad_block: 32024676da4STheodore Ts'o EXT4_ERROR_INODE(inode, "bad block %llu", 321617ba13bSMingming Cao EXT4_I(inode)->i_file_acl); 3226a797d27SDarrick J. Wong error = -EFSCORRUPTED; 323ac27a0ecSDave Kleikamp goto cleanup; 324ac27a0ecSDave Kleikamp } 3259c191f70ST Makphaibulchoke ext4_xattr_cache_insert(ext4_mb_cache, bh); 326ac27a0ecSDave Kleikamp entry = BFIRST(bh); 327617ba13bSMingming Cao error = ext4_xattr_find_entry(&entry, name_index, name, bh->b_size, 1); 3286a797d27SDarrick J. Wong if (error == -EFSCORRUPTED) 329ac27a0ecSDave Kleikamp goto bad_block; 330ac27a0ecSDave Kleikamp if (error) 331ac27a0ecSDave Kleikamp goto cleanup; 332ac27a0ecSDave Kleikamp size = le32_to_cpu(entry->e_value_size); 333ac27a0ecSDave Kleikamp if (buffer) { 334ac27a0ecSDave Kleikamp error = -ERANGE; 335ac27a0ecSDave Kleikamp if (size > buffer_size) 336ac27a0ecSDave Kleikamp goto cleanup; 337ac27a0ecSDave Kleikamp memcpy(buffer, bh->b_data + le16_to_cpu(entry->e_value_offs), 338ac27a0ecSDave Kleikamp size); 339ac27a0ecSDave Kleikamp } 340ac27a0ecSDave Kleikamp error = size; 341ac27a0ecSDave Kleikamp 342ac27a0ecSDave Kleikamp cleanup: 343ac27a0ecSDave Kleikamp brelse(bh); 344ac27a0ecSDave Kleikamp return error; 345ac27a0ecSDave Kleikamp } 346ac27a0ecSDave Kleikamp 347879b3825STao Ma int 348617ba13bSMingming Cao ext4_xattr_ibody_get(struct inode *inode, int name_index, const char *name, 349ac27a0ecSDave Kleikamp void *buffer, size_t buffer_size) 350ac27a0ecSDave Kleikamp { 351617ba13bSMingming Cao struct ext4_xattr_ibody_header *header; 352617ba13bSMingming Cao struct ext4_xattr_entry *entry; 353617ba13bSMingming Cao struct ext4_inode *raw_inode; 354617ba13bSMingming Cao struct ext4_iloc iloc; 355ac27a0ecSDave Kleikamp size_t size; 356ac27a0ecSDave Kleikamp void *end; 357ac27a0ecSDave Kleikamp int error; 358ac27a0ecSDave Kleikamp 35919f5fb7aSTheodore Ts'o if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR)) 360ac27a0ecSDave Kleikamp return -ENODATA; 361617ba13bSMingming Cao error = ext4_get_inode_loc(inode, &iloc); 362ac27a0ecSDave Kleikamp if (error) 363ac27a0ecSDave Kleikamp return error; 364617ba13bSMingming Cao raw_inode = ext4_raw_inode(&iloc); 365ac27a0ecSDave Kleikamp header = IHDR(inode, raw_inode); 366ac27a0ecSDave Kleikamp entry = IFIRST(header); 367617ba13bSMingming Cao end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; 3689e92f48cSTheodore Ts'o error = xattr_check_inode(inode, header, end); 369ac27a0ecSDave Kleikamp if (error) 370ac27a0ecSDave Kleikamp goto cleanup; 371617ba13bSMingming Cao error = ext4_xattr_find_entry(&entry, name_index, name, 372ac27a0ecSDave Kleikamp end - (void *)entry, 0); 373ac27a0ecSDave Kleikamp if (error) 374ac27a0ecSDave Kleikamp goto cleanup; 375ac27a0ecSDave Kleikamp size = le32_to_cpu(entry->e_value_size); 376ac27a0ecSDave Kleikamp if (buffer) { 377ac27a0ecSDave Kleikamp error = -ERANGE; 378ac27a0ecSDave Kleikamp if (size > buffer_size) 379ac27a0ecSDave Kleikamp goto cleanup; 380ac27a0ecSDave Kleikamp memcpy(buffer, (void *)IFIRST(header) + 381ac27a0ecSDave Kleikamp le16_to_cpu(entry->e_value_offs), size); 382ac27a0ecSDave Kleikamp } 383ac27a0ecSDave Kleikamp error = size; 384ac27a0ecSDave Kleikamp 385ac27a0ecSDave Kleikamp cleanup: 386ac27a0ecSDave Kleikamp brelse(iloc.bh); 387ac27a0ecSDave Kleikamp return error; 388ac27a0ecSDave Kleikamp } 389ac27a0ecSDave Kleikamp 390ac27a0ecSDave Kleikamp /* 391617ba13bSMingming Cao * ext4_xattr_get() 392ac27a0ecSDave Kleikamp * 393ac27a0ecSDave Kleikamp * Copy an extended attribute into the buffer 394ac27a0ecSDave Kleikamp * provided, or compute the buffer size required. 395ac27a0ecSDave Kleikamp * Buffer is NULL to compute the size of the buffer required. 396ac27a0ecSDave Kleikamp * 397ac27a0ecSDave Kleikamp * Returns a negative error number on failure, or the number of bytes 398ac27a0ecSDave Kleikamp * used / required on success. 399ac27a0ecSDave Kleikamp */ 400ac27a0ecSDave Kleikamp int 401617ba13bSMingming Cao ext4_xattr_get(struct inode *inode, int name_index, const char *name, 402ac27a0ecSDave Kleikamp void *buffer, size_t buffer_size) 403ac27a0ecSDave Kleikamp { 404ac27a0ecSDave Kleikamp int error; 405ac27a0ecSDave Kleikamp 406230b8c1aSZhang Zhen if (strlen(name) > 255) 407230b8c1aSZhang Zhen return -ERANGE; 408230b8c1aSZhang Zhen 409617ba13bSMingming Cao down_read(&EXT4_I(inode)->xattr_sem); 410617ba13bSMingming Cao error = ext4_xattr_ibody_get(inode, name_index, name, buffer, 411ac27a0ecSDave Kleikamp buffer_size); 412ac27a0ecSDave Kleikamp if (error == -ENODATA) 413617ba13bSMingming Cao error = ext4_xattr_block_get(inode, name_index, name, buffer, 414ac27a0ecSDave Kleikamp buffer_size); 415617ba13bSMingming Cao up_read(&EXT4_I(inode)->xattr_sem); 416ac27a0ecSDave Kleikamp return error; 417ac27a0ecSDave Kleikamp } 418ac27a0ecSDave Kleikamp 419ac27a0ecSDave Kleikamp static int 420431547b3SChristoph Hellwig ext4_xattr_list_entries(struct dentry *dentry, struct ext4_xattr_entry *entry, 421ac27a0ecSDave Kleikamp char *buffer, size_t buffer_size) 422ac27a0ecSDave Kleikamp { 423ac27a0ecSDave Kleikamp size_t rest = buffer_size; 424ac27a0ecSDave Kleikamp 425617ba13bSMingming Cao for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) { 42611e27528SStephen Hemminger const struct xattr_handler *handler = 427617ba13bSMingming Cao ext4_xattr_handler(entry->e_name_index); 428ac27a0ecSDave Kleikamp 429764a5c6bSAndreas Gruenbacher if (handler && (!handler->list || handler->list(dentry))) { 430764a5c6bSAndreas Gruenbacher const char *prefix = handler->prefix ?: handler->name; 431764a5c6bSAndreas Gruenbacher size_t prefix_len = strlen(prefix); 432764a5c6bSAndreas Gruenbacher size_t size = prefix_len + entry->e_name_len + 1; 433764a5c6bSAndreas Gruenbacher 434ac27a0ecSDave Kleikamp if (buffer) { 435ac27a0ecSDave Kleikamp if (size > rest) 436ac27a0ecSDave Kleikamp return -ERANGE; 437764a5c6bSAndreas Gruenbacher memcpy(buffer, prefix, prefix_len); 438764a5c6bSAndreas Gruenbacher buffer += prefix_len; 439764a5c6bSAndreas Gruenbacher memcpy(buffer, entry->e_name, entry->e_name_len); 440764a5c6bSAndreas Gruenbacher buffer += entry->e_name_len; 441764a5c6bSAndreas Gruenbacher *buffer++ = 0; 442ac27a0ecSDave Kleikamp } 443ac27a0ecSDave Kleikamp rest -= size; 444ac27a0ecSDave Kleikamp } 445ac27a0ecSDave Kleikamp } 446764a5c6bSAndreas Gruenbacher return buffer_size - rest; /* total size */ 447ac27a0ecSDave Kleikamp } 448ac27a0ecSDave Kleikamp 449ac27a0ecSDave Kleikamp static int 450431547b3SChristoph Hellwig ext4_xattr_block_list(struct dentry *dentry, char *buffer, size_t buffer_size) 451ac27a0ecSDave Kleikamp { 4522b0143b5SDavid Howells struct inode *inode = d_inode(dentry); 453ac27a0ecSDave Kleikamp struct buffer_head *bh = NULL; 454ac27a0ecSDave Kleikamp int error; 4557a2508e1SJan Kara struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); 456ac27a0ecSDave Kleikamp 457ac27a0ecSDave Kleikamp ea_idebug(inode, "buffer=%p, buffer_size=%ld", 458ac27a0ecSDave Kleikamp buffer, (long)buffer_size); 459ac27a0ecSDave Kleikamp 460ac27a0ecSDave Kleikamp error = 0; 461617ba13bSMingming Cao if (!EXT4_I(inode)->i_file_acl) 462ac27a0ecSDave Kleikamp goto cleanup; 463ace36ad4SJoe Perches ea_idebug(inode, "reading block %llu", 464ace36ad4SJoe Perches (unsigned long long)EXT4_I(inode)->i_file_acl); 465617ba13bSMingming Cao bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); 466ac27a0ecSDave Kleikamp error = -EIO; 467ac27a0ecSDave Kleikamp if (!bh) 468ac27a0ecSDave Kleikamp goto cleanup; 469ac27a0ecSDave Kleikamp ea_bdebug(bh, "b_count=%d, refcount=%d", 470ac27a0ecSDave Kleikamp atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount)); 471cc8e94fdSDarrick J. Wong if (ext4_xattr_check_block(inode, bh)) { 47224676da4STheodore Ts'o EXT4_ERROR_INODE(inode, "bad block %llu", 473617ba13bSMingming Cao EXT4_I(inode)->i_file_acl); 4746a797d27SDarrick J. Wong error = -EFSCORRUPTED; 475ac27a0ecSDave Kleikamp goto cleanup; 476ac27a0ecSDave Kleikamp } 4779c191f70ST Makphaibulchoke ext4_xattr_cache_insert(ext4_mb_cache, bh); 478431547b3SChristoph Hellwig error = ext4_xattr_list_entries(dentry, BFIRST(bh), buffer, buffer_size); 479ac27a0ecSDave Kleikamp 480ac27a0ecSDave Kleikamp cleanup: 481ac27a0ecSDave Kleikamp brelse(bh); 482ac27a0ecSDave Kleikamp 483ac27a0ecSDave Kleikamp return error; 484ac27a0ecSDave Kleikamp } 485ac27a0ecSDave Kleikamp 486ac27a0ecSDave Kleikamp static int 487431547b3SChristoph Hellwig ext4_xattr_ibody_list(struct dentry *dentry, char *buffer, size_t buffer_size) 488ac27a0ecSDave Kleikamp { 4892b0143b5SDavid Howells struct inode *inode = d_inode(dentry); 490617ba13bSMingming Cao struct ext4_xattr_ibody_header *header; 491617ba13bSMingming Cao struct ext4_inode *raw_inode; 492617ba13bSMingming Cao struct ext4_iloc iloc; 493ac27a0ecSDave Kleikamp void *end; 494ac27a0ecSDave Kleikamp int error; 495ac27a0ecSDave Kleikamp 49619f5fb7aSTheodore Ts'o if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR)) 497ac27a0ecSDave Kleikamp return 0; 498617ba13bSMingming Cao error = ext4_get_inode_loc(inode, &iloc); 499ac27a0ecSDave Kleikamp if (error) 500ac27a0ecSDave Kleikamp return error; 501617ba13bSMingming Cao raw_inode = ext4_raw_inode(&iloc); 502ac27a0ecSDave Kleikamp header = IHDR(inode, raw_inode); 503617ba13bSMingming Cao end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; 5049e92f48cSTheodore Ts'o error = xattr_check_inode(inode, header, end); 505ac27a0ecSDave Kleikamp if (error) 506ac27a0ecSDave Kleikamp goto cleanup; 507431547b3SChristoph Hellwig error = ext4_xattr_list_entries(dentry, IFIRST(header), 508ac27a0ecSDave Kleikamp buffer, buffer_size); 509ac27a0ecSDave Kleikamp 510ac27a0ecSDave Kleikamp cleanup: 511ac27a0ecSDave Kleikamp brelse(iloc.bh); 512ac27a0ecSDave Kleikamp return error; 513ac27a0ecSDave Kleikamp } 514ac27a0ecSDave Kleikamp 515ac27a0ecSDave Kleikamp /* 516617ba13bSMingming Cao * ext4_xattr_list() 517ac27a0ecSDave Kleikamp * 518ac27a0ecSDave Kleikamp * Copy a list of attribute names into the buffer 519ac27a0ecSDave Kleikamp * provided, or compute the buffer size required. 520ac27a0ecSDave Kleikamp * Buffer is NULL to compute the size of the buffer required. 521ac27a0ecSDave Kleikamp * 522ac27a0ecSDave Kleikamp * Returns a negative error number on failure, or the number of bytes 523ac27a0ecSDave Kleikamp * used / required on success. 524ac27a0ecSDave Kleikamp */ 525d3a95d47SMingming Cao static int 526431547b3SChristoph Hellwig ext4_xattr_list(struct dentry *dentry, char *buffer, size_t buffer_size) 527ac27a0ecSDave Kleikamp { 528eaeef867STheodore Ts'o int ret, ret2; 529ac27a0ecSDave Kleikamp 5302b0143b5SDavid Howells down_read(&EXT4_I(d_inode(dentry))->xattr_sem); 531eaeef867STheodore Ts'o ret = ret2 = ext4_xattr_ibody_list(dentry, buffer, buffer_size); 532eaeef867STheodore Ts'o if (ret < 0) 533eaeef867STheodore Ts'o goto errout; 534ac27a0ecSDave Kleikamp if (buffer) { 535eaeef867STheodore Ts'o buffer += ret; 536eaeef867STheodore Ts'o buffer_size -= ret; 537ac27a0ecSDave Kleikamp } 538eaeef867STheodore Ts'o ret = ext4_xattr_block_list(dentry, buffer, buffer_size); 539eaeef867STheodore Ts'o if (ret < 0) 540eaeef867STheodore Ts'o goto errout; 541eaeef867STheodore Ts'o ret += ret2; 542eaeef867STheodore Ts'o errout: 5432b0143b5SDavid Howells up_read(&EXT4_I(d_inode(dentry))->xattr_sem); 544eaeef867STheodore Ts'o return ret; 545ac27a0ecSDave Kleikamp } 546ac27a0ecSDave Kleikamp 547ac27a0ecSDave Kleikamp /* 548617ba13bSMingming Cao * If the EXT4_FEATURE_COMPAT_EXT_ATTR feature of this file system is 549ac27a0ecSDave Kleikamp * not set, set it. 550ac27a0ecSDave Kleikamp */ 551617ba13bSMingming Cao static void ext4_xattr_update_super_block(handle_t *handle, 552ac27a0ecSDave Kleikamp struct super_block *sb) 553ac27a0ecSDave Kleikamp { 554e2b911c5SDarrick J. Wong if (ext4_has_feature_xattr(sb)) 555ac27a0ecSDave Kleikamp return; 556ac27a0ecSDave Kleikamp 5575d601255Sliang xie BUFFER_TRACE(EXT4_SB(sb)->s_sbh, "get_write_access"); 558617ba13bSMingming Cao if (ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh) == 0) { 559e2b911c5SDarrick J. Wong ext4_set_feature_xattr(sb); 560a0375156STheodore Ts'o ext4_handle_dirty_super(handle, sb); 561ac27a0ecSDave Kleikamp } 562ac27a0ecSDave Kleikamp } 563ac27a0ecSDave Kleikamp 564ac27a0ecSDave Kleikamp /* 565ec4cb1aaSJan Kara * Release the xattr block BH: If the reference count is > 1, decrement it; 566ec4cb1aaSJan Kara * otherwise free the block. 567ac27a0ecSDave Kleikamp */ 568ac27a0ecSDave Kleikamp static void 569617ba13bSMingming Cao ext4_xattr_release_block(handle_t *handle, struct inode *inode, 570ac27a0ecSDave Kleikamp struct buffer_head *bh) 571ac27a0ecSDave Kleikamp { 5726048c64bSAndreas Gruenbacher struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); 5736048c64bSAndreas Gruenbacher u32 hash, ref; 5748a2bfdcbSMingming Cao int error = 0; 575ac27a0ecSDave Kleikamp 5765d601255Sliang xie BUFFER_TRACE(bh, "get_write_access"); 5778a2bfdcbSMingming Cao error = ext4_journal_get_write_access(handle, bh); 5788a2bfdcbSMingming Cao if (error) 5798a2bfdcbSMingming Cao goto out; 5808a2bfdcbSMingming Cao 5818a2bfdcbSMingming Cao lock_buffer(bh); 5826048c64bSAndreas Gruenbacher hash = le32_to_cpu(BHDR(bh)->h_hash); 5836048c64bSAndreas Gruenbacher ref = le32_to_cpu(BHDR(bh)->h_refcount); 5846048c64bSAndreas Gruenbacher if (ref == 1) { 585ac27a0ecSDave Kleikamp ea_bdebug(bh, "refcount now=0; freeing"); 58682939d79SJan Kara /* 58782939d79SJan Kara * This must happen under buffer lock for 58882939d79SJan Kara * ext4_xattr_block_set() to reliably detect freed block 58982939d79SJan Kara */ 5906048c64bSAndreas Gruenbacher mb_cache_entry_delete_block(ext4_mb_cache, hash, bh->b_blocknr); 591ac27a0ecSDave Kleikamp get_bh(bh); 592ec4cb1aaSJan Kara unlock_buffer(bh); 593e6362609STheodore Ts'o ext4_free_blocks(handle, inode, bh, 0, 1, 594e6362609STheodore Ts'o EXT4_FREE_BLOCKS_METADATA | 595e6362609STheodore Ts'o EXT4_FREE_BLOCKS_FORGET); 596ac27a0ecSDave Kleikamp } else { 5976048c64bSAndreas Gruenbacher ref--; 5986048c64bSAndreas Gruenbacher BHDR(bh)->h_refcount = cpu_to_le32(ref); 5996048c64bSAndreas Gruenbacher if (ref == EXT4_XATTR_REFCOUNT_MAX - 1) { 6006048c64bSAndreas Gruenbacher struct mb_cache_entry *ce; 6016048c64bSAndreas Gruenbacher 6026048c64bSAndreas Gruenbacher ce = mb_cache_entry_get(ext4_mb_cache, hash, 6036048c64bSAndreas Gruenbacher bh->b_blocknr); 6046048c64bSAndreas Gruenbacher if (ce) { 6056048c64bSAndreas Gruenbacher ce->e_reusable = 1; 6066048c64bSAndreas Gruenbacher mb_cache_entry_put(ext4_mb_cache, ce); 6076048c64bSAndreas Gruenbacher } 6086048c64bSAndreas Gruenbacher } 6096048c64bSAndreas Gruenbacher 610ec4cb1aaSJan Kara /* 611ec4cb1aaSJan Kara * Beware of this ugliness: Releasing of xattr block references 612ec4cb1aaSJan Kara * from different inodes can race and so we have to protect 613ec4cb1aaSJan Kara * from a race where someone else frees the block (and releases 614ec4cb1aaSJan Kara * its journal_head) before we are done dirtying the buffer. In 615ec4cb1aaSJan Kara * nojournal mode this race is harmless and we actually cannot 616ec4cb1aaSJan Kara * call ext4_handle_dirty_xattr_block() with locked buffer as 617ec4cb1aaSJan Kara * that function can call sync_dirty_buffer() so for that case 618ec4cb1aaSJan Kara * we handle the dirtying after unlocking the buffer. 619ec4cb1aaSJan Kara */ 620ec4cb1aaSJan Kara if (ext4_handle_valid(handle)) 621ec4cb1aaSJan Kara error = ext4_handle_dirty_xattr_block(handle, inode, 622ec4cb1aaSJan Kara bh); 623c1bb05a6SEric Sandeen unlock_buffer(bh); 624ec4cb1aaSJan Kara if (!ext4_handle_valid(handle)) 625ec4cb1aaSJan Kara error = ext4_handle_dirty_xattr_block(handle, inode, 626ec4cb1aaSJan Kara bh); 627ac27a0ecSDave Kleikamp if (IS_SYNC(inode)) 6280390131bSFrank Mayhar ext4_handle_sync(handle); 6291231b3a1SLukas Czerner dquot_free_block(inode, EXT4_C2B(EXT4_SB(inode->i_sb), 1)); 630ac27a0ecSDave Kleikamp ea_bdebug(bh, "refcount now=%d; releasing", 631ac27a0ecSDave Kleikamp le32_to_cpu(BHDR(bh)->h_refcount)); 632ac27a0ecSDave Kleikamp } 6338a2bfdcbSMingming Cao out: 6348a2bfdcbSMingming Cao ext4_std_error(inode->i_sb, error); 6358a2bfdcbSMingming Cao return; 636ac27a0ecSDave Kleikamp } 637ac27a0ecSDave Kleikamp 6386dd4ee7cSKalpak Shah /* 6396dd4ee7cSKalpak Shah * Find the available free space for EAs. This also returns the total number of 6406dd4ee7cSKalpak Shah * bytes used by EA entries. 6416dd4ee7cSKalpak Shah */ 6426dd4ee7cSKalpak Shah static size_t ext4_xattr_free_space(struct ext4_xattr_entry *last, 6436dd4ee7cSKalpak Shah size_t *min_offs, void *base, int *total) 6446dd4ee7cSKalpak Shah { 6456dd4ee7cSKalpak Shah for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { 6461cba4237SJan Kara if (last->e_value_size) { 6476dd4ee7cSKalpak Shah size_t offs = le16_to_cpu(last->e_value_offs); 6486dd4ee7cSKalpak Shah if (offs < *min_offs) 6496dd4ee7cSKalpak Shah *min_offs = offs; 6506dd4ee7cSKalpak Shah } 6517b1b2c1bSTheodore Ts'o if (total) 6527b1b2c1bSTheodore Ts'o *total += EXT4_XATTR_LEN(last->e_name_len); 6536dd4ee7cSKalpak Shah } 6546dd4ee7cSKalpak Shah return (*min_offs - ((void *)last - base) - sizeof(__u32)); 6556dd4ee7cSKalpak Shah } 6566dd4ee7cSKalpak Shah 657ac27a0ecSDave Kleikamp static int 658617ba13bSMingming Cao ext4_xattr_set_entry(struct ext4_xattr_info *i, struct ext4_xattr_search *s) 659ac27a0ecSDave Kleikamp { 660617ba13bSMingming Cao struct ext4_xattr_entry *last; 661ac27a0ecSDave Kleikamp size_t free, min_offs = s->end - s->base, name_len = strlen(i->name); 662ac27a0ecSDave Kleikamp 663ac27a0ecSDave Kleikamp /* Compute min_offs and last. */ 664ac27a0ecSDave Kleikamp last = s->first; 665617ba13bSMingming Cao for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { 6661cba4237SJan Kara if (last->e_value_size) { 667ac27a0ecSDave Kleikamp size_t offs = le16_to_cpu(last->e_value_offs); 668ac27a0ecSDave Kleikamp if (offs < min_offs) 669ac27a0ecSDave Kleikamp min_offs = offs; 670ac27a0ecSDave Kleikamp } 671ac27a0ecSDave Kleikamp } 672ac27a0ecSDave Kleikamp free = min_offs - ((void *)last - s->base) - sizeof(__u32); 673ac27a0ecSDave Kleikamp if (!s->not_found) { 6741cba4237SJan Kara if (s->here->e_value_size) { 675ac27a0ecSDave Kleikamp size_t size = le32_to_cpu(s->here->e_value_size); 676617ba13bSMingming Cao free += EXT4_XATTR_SIZE(size); 677ac27a0ecSDave Kleikamp } 678617ba13bSMingming Cao free += EXT4_XATTR_LEN(name_len); 679ac27a0ecSDave Kleikamp } 680ac27a0ecSDave Kleikamp if (i->value) { 6815f80f62aSWei Yuan if (free < EXT4_XATTR_LEN(name_len) + 682617ba13bSMingming Cao EXT4_XATTR_SIZE(i->value_len)) 683ac27a0ecSDave Kleikamp return -ENOSPC; 684ac27a0ecSDave Kleikamp } 685ac27a0ecSDave Kleikamp 686ac27a0ecSDave Kleikamp if (i->value && s->not_found) { 687ac27a0ecSDave Kleikamp /* Insert the new name. */ 688617ba13bSMingming Cao size_t size = EXT4_XATTR_LEN(name_len); 689ac27a0ecSDave Kleikamp size_t rest = (void *)last - (void *)s->here + sizeof(__u32); 690ac27a0ecSDave Kleikamp memmove((void *)s->here + size, s->here, rest); 691ac27a0ecSDave Kleikamp memset(s->here, 0, size); 692ac27a0ecSDave Kleikamp s->here->e_name_index = i->name_index; 693ac27a0ecSDave Kleikamp s->here->e_name_len = name_len; 694ac27a0ecSDave Kleikamp memcpy(s->here->e_name, i->name, name_len); 695ac27a0ecSDave Kleikamp } else { 6961cba4237SJan Kara if (s->here->e_value_size) { 697ac27a0ecSDave Kleikamp void *first_val = s->base + min_offs; 698ac27a0ecSDave Kleikamp size_t offs = le16_to_cpu(s->here->e_value_offs); 699ac27a0ecSDave Kleikamp void *val = s->base + offs; 700617ba13bSMingming Cao size_t size = EXT4_XATTR_SIZE( 701ac27a0ecSDave Kleikamp le32_to_cpu(s->here->e_value_size)); 702ac27a0ecSDave Kleikamp 703617ba13bSMingming Cao if (i->value && size == EXT4_XATTR_SIZE(i->value_len)) { 704ac27a0ecSDave Kleikamp /* The old and the new value have the same 705ac27a0ecSDave Kleikamp size. Just replace. */ 706ac27a0ecSDave Kleikamp s->here->e_value_size = 707ac27a0ecSDave Kleikamp cpu_to_le32(i->value_len); 708bd9926e8STheodore Ts'o if (i->value == EXT4_ZERO_XATTR_VALUE) { 709bd9926e8STheodore Ts'o memset(val, 0, size); 710bd9926e8STheodore Ts'o } else { 711bd9926e8STheodore Ts'o /* Clear pad bytes first. */ 712617ba13bSMingming Cao memset(val + size - EXT4_XATTR_PAD, 0, 713bd9926e8STheodore Ts'o EXT4_XATTR_PAD); 714ac27a0ecSDave Kleikamp memcpy(val, i->value, i->value_len); 715bd9926e8STheodore Ts'o } 716ac27a0ecSDave Kleikamp return 0; 717ac27a0ecSDave Kleikamp } 718ac27a0ecSDave Kleikamp 719ac27a0ecSDave Kleikamp /* Remove the old value. */ 720ac27a0ecSDave Kleikamp memmove(first_val + size, first_val, val - first_val); 721ac27a0ecSDave Kleikamp memset(first_val, 0, size); 722ac27a0ecSDave Kleikamp s->here->e_value_size = 0; 723ac27a0ecSDave Kleikamp s->here->e_value_offs = 0; 724ac27a0ecSDave Kleikamp min_offs += size; 725ac27a0ecSDave Kleikamp 726ac27a0ecSDave Kleikamp /* Adjust all value offsets. */ 727ac27a0ecSDave Kleikamp last = s->first; 728ac27a0ecSDave Kleikamp while (!IS_LAST_ENTRY(last)) { 729ac27a0ecSDave Kleikamp size_t o = le16_to_cpu(last->e_value_offs); 7301cba4237SJan Kara if (last->e_value_size && o < offs) 731ac27a0ecSDave Kleikamp last->e_value_offs = 732ac27a0ecSDave Kleikamp cpu_to_le16(o + size); 733617ba13bSMingming Cao last = EXT4_XATTR_NEXT(last); 734ac27a0ecSDave Kleikamp } 735ac27a0ecSDave Kleikamp } 736ac27a0ecSDave Kleikamp if (!i->value) { 737ac27a0ecSDave Kleikamp /* Remove the old name. */ 738617ba13bSMingming Cao size_t size = EXT4_XATTR_LEN(name_len); 739ac27a0ecSDave Kleikamp last = ENTRY((void *)last - size); 740ac27a0ecSDave Kleikamp memmove(s->here, (void *)s->here + size, 741ac27a0ecSDave Kleikamp (void *)last - (void *)s->here + sizeof(__u32)); 742ac27a0ecSDave Kleikamp memset(last, 0, size); 743ac27a0ecSDave Kleikamp } 744ac27a0ecSDave Kleikamp } 745ac27a0ecSDave Kleikamp 746ac27a0ecSDave Kleikamp if (i->value) { 747ac27a0ecSDave Kleikamp /* Insert the new value. */ 748ac27a0ecSDave Kleikamp s->here->e_value_size = cpu_to_le32(i->value_len); 749ac27a0ecSDave Kleikamp if (i->value_len) { 750617ba13bSMingming Cao size_t size = EXT4_XATTR_SIZE(i->value_len); 751ac27a0ecSDave Kleikamp void *val = s->base + min_offs - size; 752ac27a0ecSDave Kleikamp s->here->e_value_offs = cpu_to_le16(min_offs - size); 753bd9926e8STheodore Ts'o if (i->value == EXT4_ZERO_XATTR_VALUE) { 754bd9926e8STheodore Ts'o memset(val, 0, size); 755bd9926e8STheodore Ts'o } else { 756bd9926e8STheodore Ts'o /* Clear the pad bytes first. */ 757617ba13bSMingming Cao memset(val + size - EXT4_XATTR_PAD, 0, 758bd9926e8STheodore Ts'o EXT4_XATTR_PAD); 759ac27a0ecSDave Kleikamp memcpy(val, i->value, i->value_len); 760ac27a0ecSDave Kleikamp } 761ac27a0ecSDave Kleikamp } 762bd9926e8STheodore Ts'o } 763ac27a0ecSDave Kleikamp return 0; 764ac27a0ecSDave Kleikamp } 765ac27a0ecSDave Kleikamp 766617ba13bSMingming Cao struct ext4_xattr_block_find { 767617ba13bSMingming Cao struct ext4_xattr_search s; 768ac27a0ecSDave Kleikamp struct buffer_head *bh; 769ac27a0ecSDave Kleikamp }; 770ac27a0ecSDave Kleikamp 771ac27a0ecSDave Kleikamp static int 772617ba13bSMingming Cao ext4_xattr_block_find(struct inode *inode, struct ext4_xattr_info *i, 773617ba13bSMingming Cao struct ext4_xattr_block_find *bs) 774ac27a0ecSDave Kleikamp { 775ac27a0ecSDave Kleikamp struct super_block *sb = inode->i_sb; 776ac27a0ecSDave Kleikamp int error; 777ac27a0ecSDave Kleikamp 778ac27a0ecSDave Kleikamp ea_idebug(inode, "name=%d.%s, value=%p, value_len=%ld", 779ac27a0ecSDave Kleikamp i->name_index, i->name, i->value, (long)i->value_len); 780ac27a0ecSDave Kleikamp 781617ba13bSMingming Cao if (EXT4_I(inode)->i_file_acl) { 782ac27a0ecSDave Kleikamp /* The inode already has an extended attribute block. */ 783617ba13bSMingming Cao bs->bh = sb_bread(sb, EXT4_I(inode)->i_file_acl); 784ac27a0ecSDave Kleikamp error = -EIO; 785ac27a0ecSDave Kleikamp if (!bs->bh) 786ac27a0ecSDave Kleikamp goto cleanup; 787ac27a0ecSDave Kleikamp ea_bdebug(bs->bh, "b_count=%d, refcount=%d", 788ac27a0ecSDave Kleikamp atomic_read(&(bs->bh->b_count)), 789ac27a0ecSDave Kleikamp le32_to_cpu(BHDR(bs->bh)->h_refcount)); 790cc8e94fdSDarrick J. Wong if (ext4_xattr_check_block(inode, bs->bh)) { 79124676da4STheodore Ts'o EXT4_ERROR_INODE(inode, "bad block %llu", 79224676da4STheodore Ts'o EXT4_I(inode)->i_file_acl); 7936a797d27SDarrick J. Wong error = -EFSCORRUPTED; 794ac27a0ecSDave Kleikamp goto cleanup; 795ac27a0ecSDave Kleikamp } 796ac27a0ecSDave Kleikamp /* Find the named attribute. */ 797ac27a0ecSDave Kleikamp bs->s.base = BHDR(bs->bh); 798ac27a0ecSDave Kleikamp bs->s.first = BFIRST(bs->bh); 799ac27a0ecSDave Kleikamp bs->s.end = bs->bh->b_data + bs->bh->b_size; 800ac27a0ecSDave Kleikamp bs->s.here = bs->s.first; 801617ba13bSMingming Cao error = ext4_xattr_find_entry(&bs->s.here, i->name_index, 802ac27a0ecSDave Kleikamp i->name, bs->bh->b_size, 1); 803ac27a0ecSDave Kleikamp if (error && error != -ENODATA) 804ac27a0ecSDave Kleikamp goto cleanup; 805ac27a0ecSDave Kleikamp bs->s.not_found = error; 806ac27a0ecSDave Kleikamp } 807ac27a0ecSDave Kleikamp error = 0; 808ac27a0ecSDave Kleikamp 809ac27a0ecSDave Kleikamp cleanup: 810ac27a0ecSDave Kleikamp return error; 811ac27a0ecSDave Kleikamp } 812ac27a0ecSDave Kleikamp 813ac27a0ecSDave Kleikamp static int 814617ba13bSMingming Cao ext4_xattr_block_set(handle_t *handle, struct inode *inode, 815617ba13bSMingming Cao struct ext4_xattr_info *i, 816617ba13bSMingming Cao struct ext4_xattr_block_find *bs) 817ac27a0ecSDave Kleikamp { 818ac27a0ecSDave Kleikamp struct super_block *sb = inode->i_sb; 819ac27a0ecSDave Kleikamp struct buffer_head *new_bh = NULL; 820617ba13bSMingming Cao struct ext4_xattr_search *s = &bs->s; 8217a2508e1SJan Kara struct mb_cache_entry *ce = NULL; 8228a2bfdcbSMingming Cao int error = 0; 8237a2508e1SJan Kara struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); 824ac27a0ecSDave Kleikamp 825617ba13bSMingming Cao #define header(x) ((struct ext4_xattr_header *)(x)) 826ac27a0ecSDave Kleikamp 827ac27a0ecSDave Kleikamp if (i->value && i->value_len > sb->s_blocksize) 828ac27a0ecSDave Kleikamp return -ENOSPC; 829ac27a0ecSDave Kleikamp if (s->base) { 8305d601255Sliang xie BUFFER_TRACE(bs->bh, "get_write_access"); 8318a2bfdcbSMingming Cao error = ext4_journal_get_write_access(handle, bs->bh); 8328a2bfdcbSMingming Cao if (error) 8338a2bfdcbSMingming Cao goto cleanup; 8348a2bfdcbSMingming Cao lock_buffer(bs->bh); 8358a2bfdcbSMingming Cao 836ac27a0ecSDave Kleikamp if (header(s->base)->h_refcount == cpu_to_le32(1)) { 83782939d79SJan Kara __u32 hash = le32_to_cpu(BHDR(bs->bh)->h_hash); 83882939d79SJan Kara 83982939d79SJan Kara /* 84082939d79SJan Kara * This must happen under buffer lock for 84182939d79SJan Kara * ext4_xattr_block_set() to reliably detect modified 84282939d79SJan Kara * block 84382939d79SJan Kara */ 8447a2508e1SJan Kara mb_cache_entry_delete_block(ext4_mb_cache, hash, 84582939d79SJan Kara bs->bh->b_blocknr); 846ac27a0ecSDave Kleikamp ea_bdebug(bs->bh, "modifying in-place"); 847617ba13bSMingming Cao error = ext4_xattr_set_entry(i, s); 848ac27a0ecSDave Kleikamp if (!error) { 849ac27a0ecSDave Kleikamp if (!IS_LAST_ENTRY(s->first)) 850617ba13bSMingming Cao ext4_xattr_rehash(header(s->base), 851ac27a0ecSDave Kleikamp s->here); 8529c191f70ST Makphaibulchoke ext4_xattr_cache_insert(ext4_mb_cache, 8539c191f70ST Makphaibulchoke bs->bh); 854ac27a0ecSDave Kleikamp } 855ac27a0ecSDave Kleikamp unlock_buffer(bs->bh); 8566a797d27SDarrick J. Wong if (error == -EFSCORRUPTED) 857ac27a0ecSDave Kleikamp goto bad_block; 858ac27a0ecSDave Kleikamp if (!error) 859cc8e94fdSDarrick J. Wong error = ext4_handle_dirty_xattr_block(handle, 8600390131bSFrank Mayhar inode, 861ac27a0ecSDave Kleikamp bs->bh); 862ac27a0ecSDave Kleikamp if (error) 863ac27a0ecSDave Kleikamp goto cleanup; 864ac27a0ecSDave Kleikamp goto inserted; 865ac27a0ecSDave Kleikamp } else { 866ac27a0ecSDave Kleikamp int offset = (char *)s->here - bs->bh->b_data; 867ac27a0ecSDave Kleikamp 8688a2bfdcbSMingming Cao unlock_buffer(bs->bh); 869ac27a0ecSDave Kleikamp ea_bdebug(bs->bh, "cloning"); 870216553c4SJosef Bacik s->base = kmalloc(bs->bh->b_size, GFP_NOFS); 871ac27a0ecSDave Kleikamp error = -ENOMEM; 872ac27a0ecSDave Kleikamp if (s->base == NULL) 873ac27a0ecSDave Kleikamp goto cleanup; 874ac27a0ecSDave Kleikamp memcpy(s->base, BHDR(bs->bh), bs->bh->b_size); 875ac27a0ecSDave Kleikamp s->first = ENTRY(header(s->base)+1); 876ac27a0ecSDave Kleikamp header(s->base)->h_refcount = cpu_to_le32(1); 877ac27a0ecSDave Kleikamp s->here = ENTRY(s->base + offset); 878ac27a0ecSDave Kleikamp s->end = s->base + bs->bh->b_size; 879ac27a0ecSDave Kleikamp } 880ac27a0ecSDave Kleikamp } else { 881ac27a0ecSDave Kleikamp /* Allocate a buffer where we construct the new block. */ 882216553c4SJosef Bacik s->base = kzalloc(sb->s_blocksize, GFP_NOFS); 883ac27a0ecSDave Kleikamp /* assert(header == s->base) */ 884ac27a0ecSDave Kleikamp error = -ENOMEM; 885ac27a0ecSDave Kleikamp if (s->base == NULL) 886ac27a0ecSDave Kleikamp goto cleanup; 887617ba13bSMingming Cao header(s->base)->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC); 888ac27a0ecSDave Kleikamp header(s->base)->h_blocks = cpu_to_le32(1); 889ac27a0ecSDave Kleikamp header(s->base)->h_refcount = cpu_to_le32(1); 890ac27a0ecSDave Kleikamp s->first = ENTRY(header(s->base)+1); 891ac27a0ecSDave Kleikamp s->here = ENTRY(header(s->base)+1); 892ac27a0ecSDave Kleikamp s->end = s->base + sb->s_blocksize; 893ac27a0ecSDave Kleikamp } 894ac27a0ecSDave Kleikamp 895617ba13bSMingming Cao error = ext4_xattr_set_entry(i, s); 8966a797d27SDarrick J. Wong if (error == -EFSCORRUPTED) 897ac27a0ecSDave Kleikamp goto bad_block; 898ac27a0ecSDave Kleikamp if (error) 899ac27a0ecSDave Kleikamp goto cleanup; 900ac27a0ecSDave Kleikamp if (!IS_LAST_ENTRY(s->first)) 901617ba13bSMingming Cao ext4_xattr_rehash(header(s->base), s->here); 902ac27a0ecSDave Kleikamp 903ac27a0ecSDave Kleikamp inserted: 904ac27a0ecSDave Kleikamp if (!IS_LAST_ENTRY(s->first)) { 905617ba13bSMingming Cao new_bh = ext4_xattr_cache_find(inode, header(s->base), &ce); 906ac27a0ecSDave Kleikamp if (new_bh) { 907ac27a0ecSDave Kleikamp /* We found an identical block in the cache. */ 908ac27a0ecSDave Kleikamp if (new_bh == bs->bh) 909ac27a0ecSDave Kleikamp ea_bdebug(new_bh, "keeping"); 910ac27a0ecSDave Kleikamp else { 9116048c64bSAndreas Gruenbacher u32 ref; 9126048c64bSAndreas Gruenbacher 913ac27a0ecSDave Kleikamp /* The old block is released after updating 914ac27a0ecSDave Kleikamp the inode. */ 9151231b3a1SLukas Czerner error = dquot_alloc_block(inode, 9161231b3a1SLukas Czerner EXT4_C2B(EXT4_SB(sb), 1)); 9175dd4056dSChristoph Hellwig if (error) 918ac27a0ecSDave Kleikamp goto cleanup; 9195d601255Sliang xie BUFFER_TRACE(new_bh, "get_write_access"); 920617ba13bSMingming Cao error = ext4_journal_get_write_access(handle, 921ac27a0ecSDave Kleikamp new_bh); 922ac27a0ecSDave Kleikamp if (error) 923ac27a0ecSDave Kleikamp goto cleanup_dquot; 924ac27a0ecSDave Kleikamp lock_buffer(new_bh); 92582939d79SJan Kara /* 92682939d79SJan Kara * We have to be careful about races with 9276048c64bSAndreas Gruenbacher * freeing, rehashing or adding references to 9286048c64bSAndreas Gruenbacher * xattr block. Once we hold buffer lock xattr 9296048c64bSAndreas Gruenbacher * block's state is stable so we can check 9306048c64bSAndreas Gruenbacher * whether the block got freed / rehashed or 9316048c64bSAndreas Gruenbacher * not. Since we unhash mbcache entry under 9326048c64bSAndreas Gruenbacher * buffer lock when freeing / rehashing xattr 9336048c64bSAndreas Gruenbacher * block, checking whether entry is still 9346048c64bSAndreas Gruenbacher * hashed is reliable. Same rules hold for 9356048c64bSAndreas Gruenbacher * e_reusable handling. 93682939d79SJan Kara */ 9376048c64bSAndreas Gruenbacher if (hlist_bl_unhashed(&ce->e_hash_list) || 9386048c64bSAndreas Gruenbacher !ce->e_reusable) { 93982939d79SJan Kara /* 94082939d79SJan Kara * Undo everything and check mbcache 94182939d79SJan Kara * again. 94282939d79SJan Kara */ 94382939d79SJan Kara unlock_buffer(new_bh); 94482939d79SJan Kara dquot_free_block(inode, 94582939d79SJan Kara EXT4_C2B(EXT4_SB(sb), 94682939d79SJan Kara 1)); 94782939d79SJan Kara brelse(new_bh); 9487a2508e1SJan Kara mb_cache_entry_put(ext4_mb_cache, ce); 94982939d79SJan Kara ce = NULL; 95082939d79SJan Kara new_bh = NULL; 95182939d79SJan Kara goto inserted; 95282939d79SJan Kara } 9536048c64bSAndreas Gruenbacher ref = le32_to_cpu(BHDR(new_bh)->h_refcount) + 1; 9546048c64bSAndreas Gruenbacher BHDR(new_bh)->h_refcount = cpu_to_le32(ref); 9556048c64bSAndreas Gruenbacher if (ref >= EXT4_XATTR_REFCOUNT_MAX) 9566048c64bSAndreas Gruenbacher ce->e_reusable = 0; 957ac27a0ecSDave Kleikamp ea_bdebug(new_bh, "reusing; refcount now=%d", 9586048c64bSAndreas Gruenbacher ref); 959ac27a0ecSDave Kleikamp unlock_buffer(new_bh); 960cc8e94fdSDarrick J. Wong error = ext4_handle_dirty_xattr_block(handle, 9610390131bSFrank Mayhar inode, 962ac27a0ecSDave Kleikamp new_bh); 963ac27a0ecSDave Kleikamp if (error) 964ac27a0ecSDave Kleikamp goto cleanup_dquot; 965ac27a0ecSDave Kleikamp } 9667a2508e1SJan Kara mb_cache_entry_touch(ext4_mb_cache, ce); 9677a2508e1SJan Kara mb_cache_entry_put(ext4_mb_cache, ce); 968ac27a0ecSDave Kleikamp ce = NULL; 969ac27a0ecSDave Kleikamp } else if (bs->bh && s->base == bs->bh->b_data) { 970ac27a0ecSDave Kleikamp /* We were modifying this block in-place. */ 971ac27a0ecSDave Kleikamp ea_bdebug(bs->bh, "keeping this block"); 972ac27a0ecSDave Kleikamp new_bh = bs->bh; 973ac27a0ecSDave Kleikamp get_bh(new_bh); 974ac27a0ecSDave Kleikamp } else { 975ac27a0ecSDave Kleikamp /* We need to allocate a new block */ 976fb0a387dSEric Sandeen ext4_fsblk_t goal, block; 977fb0a387dSEric Sandeen 978fb0a387dSEric Sandeen goal = ext4_group_first_block_no(sb, 979d00a6d7bSAkinobu Mita EXT4_I(inode)->i_block_group); 980fb0a387dSEric Sandeen 981fb0a387dSEric Sandeen /* non-extent files can't have physical blocks past 2^32 */ 98212e9b892SDmitry Monakhov if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) 983fb0a387dSEric Sandeen goal = goal & EXT4_MAX_BLOCK_FILE_PHYS; 984fb0a387dSEric Sandeen 98555f020dbSAllison Henderson block = ext4_new_meta_blocks(handle, inode, goal, 0, 98655f020dbSAllison Henderson NULL, &error); 987ac27a0ecSDave Kleikamp if (error) 988ac27a0ecSDave Kleikamp goto cleanup; 989fb0a387dSEric Sandeen 99012e9b892SDmitry Monakhov if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) 991fb0a387dSEric Sandeen BUG_ON(block > EXT4_MAX_BLOCK_FILE_PHYS); 992fb0a387dSEric Sandeen 993ace36ad4SJoe Perches ea_idebug(inode, "creating block %llu", 994ace36ad4SJoe Perches (unsigned long long)block); 995ac27a0ecSDave Kleikamp 996ac27a0ecSDave Kleikamp new_bh = sb_getblk(sb, block); 997aebf0243SWang Shilong if (unlikely(!new_bh)) { 998860d21e2STheodore Ts'o error = -ENOMEM; 999ac27a0ecSDave Kleikamp getblk_failed: 10007dc57615SPeter Huewe ext4_free_blocks(handle, inode, NULL, block, 1, 1001e6362609STheodore Ts'o EXT4_FREE_BLOCKS_METADATA); 1002ac27a0ecSDave Kleikamp goto cleanup; 1003ac27a0ecSDave Kleikamp } 1004ac27a0ecSDave Kleikamp lock_buffer(new_bh); 1005617ba13bSMingming Cao error = ext4_journal_get_create_access(handle, new_bh); 1006ac27a0ecSDave Kleikamp if (error) { 1007ac27a0ecSDave Kleikamp unlock_buffer(new_bh); 1008860d21e2STheodore Ts'o error = -EIO; 1009ac27a0ecSDave Kleikamp goto getblk_failed; 1010ac27a0ecSDave Kleikamp } 1011ac27a0ecSDave Kleikamp memcpy(new_bh->b_data, s->base, new_bh->b_size); 1012ac27a0ecSDave Kleikamp set_buffer_uptodate(new_bh); 1013ac27a0ecSDave Kleikamp unlock_buffer(new_bh); 10149c191f70ST Makphaibulchoke ext4_xattr_cache_insert(ext4_mb_cache, new_bh); 1015cc8e94fdSDarrick J. Wong error = ext4_handle_dirty_xattr_block(handle, 10160390131bSFrank Mayhar inode, new_bh); 1017ac27a0ecSDave Kleikamp if (error) 1018ac27a0ecSDave Kleikamp goto cleanup; 1019ac27a0ecSDave Kleikamp } 1020ac27a0ecSDave Kleikamp } 1021ac27a0ecSDave Kleikamp 1022ac27a0ecSDave Kleikamp /* Update the inode. */ 1023617ba13bSMingming Cao EXT4_I(inode)->i_file_acl = new_bh ? new_bh->b_blocknr : 0; 1024ac27a0ecSDave Kleikamp 1025ac27a0ecSDave Kleikamp /* Drop the previous xattr block. */ 1026ac27a0ecSDave Kleikamp if (bs->bh && bs->bh != new_bh) 1027617ba13bSMingming Cao ext4_xattr_release_block(handle, inode, bs->bh); 1028ac27a0ecSDave Kleikamp error = 0; 1029ac27a0ecSDave Kleikamp 1030ac27a0ecSDave Kleikamp cleanup: 1031ac27a0ecSDave Kleikamp if (ce) 10327a2508e1SJan Kara mb_cache_entry_put(ext4_mb_cache, ce); 1033ac27a0ecSDave Kleikamp brelse(new_bh); 1034ac27a0ecSDave Kleikamp if (!(bs->bh && s->base == bs->bh->b_data)) 1035ac27a0ecSDave Kleikamp kfree(s->base); 1036ac27a0ecSDave Kleikamp 1037ac27a0ecSDave Kleikamp return error; 1038ac27a0ecSDave Kleikamp 1039ac27a0ecSDave Kleikamp cleanup_dquot: 10401231b3a1SLukas Czerner dquot_free_block(inode, EXT4_C2B(EXT4_SB(sb), 1)); 1041ac27a0ecSDave Kleikamp goto cleanup; 1042ac27a0ecSDave Kleikamp 1043ac27a0ecSDave Kleikamp bad_block: 104424676da4STheodore Ts'o EXT4_ERROR_INODE(inode, "bad block %llu", 104524676da4STheodore Ts'o EXT4_I(inode)->i_file_acl); 1046ac27a0ecSDave Kleikamp goto cleanup; 1047ac27a0ecSDave Kleikamp 1048ac27a0ecSDave Kleikamp #undef header 1049ac27a0ecSDave Kleikamp } 1050ac27a0ecSDave Kleikamp 1051879b3825STao Ma int ext4_xattr_ibody_find(struct inode *inode, struct ext4_xattr_info *i, 1052617ba13bSMingming Cao struct ext4_xattr_ibody_find *is) 1053ac27a0ecSDave Kleikamp { 1054617ba13bSMingming Cao struct ext4_xattr_ibody_header *header; 1055617ba13bSMingming Cao struct ext4_inode *raw_inode; 1056ac27a0ecSDave Kleikamp int error; 1057ac27a0ecSDave Kleikamp 1058617ba13bSMingming Cao if (EXT4_I(inode)->i_extra_isize == 0) 1059ac27a0ecSDave Kleikamp return 0; 1060617ba13bSMingming Cao raw_inode = ext4_raw_inode(&is->iloc); 1061ac27a0ecSDave Kleikamp header = IHDR(inode, raw_inode); 1062ac27a0ecSDave Kleikamp is->s.base = is->s.first = IFIRST(header); 1063ac27a0ecSDave Kleikamp is->s.here = is->s.first; 1064617ba13bSMingming Cao is->s.end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; 106519f5fb7aSTheodore Ts'o if (ext4_test_inode_state(inode, EXT4_STATE_XATTR)) { 10669e92f48cSTheodore Ts'o error = xattr_check_inode(inode, header, is->s.end); 1067ac27a0ecSDave Kleikamp if (error) 1068ac27a0ecSDave Kleikamp return error; 1069ac27a0ecSDave Kleikamp /* Find the named attribute. */ 1070617ba13bSMingming Cao error = ext4_xattr_find_entry(&is->s.here, i->name_index, 1071ac27a0ecSDave Kleikamp i->name, is->s.end - 1072ac27a0ecSDave Kleikamp (void *)is->s.base, 0); 1073ac27a0ecSDave Kleikamp if (error && error != -ENODATA) 1074ac27a0ecSDave Kleikamp return error; 1075ac27a0ecSDave Kleikamp is->s.not_found = error; 1076ac27a0ecSDave Kleikamp } 1077ac27a0ecSDave Kleikamp return 0; 1078ac27a0ecSDave Kleikamp } 1079ac27a0ecSDave Kleikamp 10800d812f77STao Ma int ext4_xattr_ibody_inline_set(handle_t *handle, struct inode *inode, 10810d812f77STao Ma struct ext4_xattr_info *i, 10820d812f77STao Ma struct ext4_xattr_ibody_find *is) 10830d812f77STao Ma { 10840d812f77STao Ma struct ext4_xattr_ibody_header *header; 10850d812f77STao Ma struct ext4_xattr_search *s = &is->s; 10860d812f77STao Ma int error; 10870d812f77STao Ma 10880d812f77STao Ma if (EXT4_I(inode)->i_extra_isize == 0) 10890d812f77STao Ma return -ENOSPC; 10900d812f77STao Ma error = ext4_xattr_set_entry(i, s); 10910d812f77STao Ma if (error) { 10920d812f77STao Ma if (error == -ENOSPC && 10930d812f77STao Ma ext4_has_inline_data(inode)) { 10940d812f77STao Ma error = ext4_try_to_evict_inline_data(handle, inode, 10950d812f77STao Ma EXT4_XATTR_LEN(strlen(i->name) + 10960d812f77STao Ma EXT4_XATTR_SIZE(i->value_len))); 10970d812f77STao Ma if (error) 10980d812f77STao Ma return error; 10990d812f77STao Ma error = ext4_xattr_ibody_find(inode, i, is); 11000d812f77STao Ma if (error) 11010d812f77STao Ma return error; 11020d812f77STao Ma error = ext4_xattr_set_entry(i, s); 11030d812f77STao Ma } 11040d812f77STao Ma if (error) 11050d812f77STao Ma return error; 11060d812f77STao Ma } 11070d812f77STao Ma header = IHDR(inode, ext4_raw_inode(&is->iloc)); 11080d812f77STao Ma if (!IS_LAST_ENTRY(s->first)) { 11090d812f77STao Ma header->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC); 11100d812f77STao Ma ext4_set_inode_state(inode, EXT4_STATE_XATTR); 11110d812f77STao Ma } else { 11120d812f77STao Ma header->h_magic = cpu_to_le32(0); 11130d812f77STao Ma ext4_clear_inode_state(inode, EXT4_STATE_XATTR); 11140d812f77STao Ma } 11150d812f77STao Ma return 0; 11160d812f77STao Ma } 11170d812f77STao Ma 11180d812f77STao Ma static int ext4_xattr_ibody_set(handle_t *handle, struct inode *inode, 1119617ba13bSMingming Cao struct ext4_xattr_info *i, 1120617ba13bSMingming Cao struct ext4_xattr_ibody_find *is) 1121ac27a0ecSDave Kleikamp { 1122617ba13bSMingming Cao struct ext4_xattr_ibody_header *header; 1123617ba13bSMingming Cao struct ext4_xattr_search *s = &is->s; 1124ac27a0ecSDave Kleikamp int error; 1125ac27a0ecSDave Kleikamp 1126617ba13bSMingming Cao if (EXT4_I(inode)->i_extra_isize == 0) 1127ac27a0ecSDave Kleikamp return -ENOSPC; 1128617ba13bSMingming Cao error = ext4_xattr_set_entry(i, s); 1129ac27a0ecSDave Kleikamp if (error) 1130ac27a0ecSDave Kleikamp return error; 1131617ba13bSMingming Cao header = IHDR(inode, ext4_raw_inode(&is->iloc)); 1132ac27a0ecSDave Kleikamp if (!IS_LAST_ENTRY(s->first)) { 1133617ba13bSMingming Cao header->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC); 113419f5fb7aSTheodore Ts'o ext4_set_inode_state(inode, EXT4_STATE_XATTR); 1135ac27a0ecSDave Kleikamp } else { 1136ac27a0ecSDave Kleikamp header->h_magic = cpu_to_le32(0); 113719f5fb7aSTheodore Ts'o ext4_clear_inode_state(inode, EXT4_STATE_XATTR); 1138ac27a0ecSDave Kleikamp } 1139ac27a0ecSDave Kleikamp return 0; 1140ac27a0ecSDave Kleikamp } 1141ac27a0ecSDave Kleikamp 11423fd16462SJan Kara static int ext4_xattr_value_same(struct ext4_xattr_search *s, 11433fd16462SJan Kara struct ext4_xattr_info *i) 11443fd16462SJan Kara { 11453fd16462SJan Kara void *value; 11463fd16462SJan Kara 11473fd16462SJan Kara if (le32_to_cpu(s->here->e_value_size) != i->value_len) 11483fd16462SJan Kara return 0; 11493fd16462SJan Kara value = ((void *)s->base) + le16_to_cpu(s->here->e_value_offs); 11503fd16462SJan Kara return !memcmp(value, i->value, i->value_len); 11513fd16462SJan Kara } 11523fd16462SJan Kara 1153ac27a0ecSDave Kleikamp /* 1154617ba13bSMingming Cao * ext4_xattr_set_handle() 1155ac27a0ecSDave Kleikamp * 11566e9510b0SWang Sheng-Hui * Create, replace or remove an extended attribute for this inode. Value 1157ac27a0ecSDave Kleikamp * is NULL to remove an existing extended attribute, and non-NULL to 1158ac27a0ecSDave Kleikamp * either replace an existing extended attribute, or create a new extended 1159ac27a0ecSDave Kleikamp * attribute. The flags XATTR_REPLACE and XATTR_CREATE 1160ac27a0ecSDave Kleikamp * specify that an extended attribute must exist and must not exist 1161ac27a0ecSDave Kleikamp * previous to the call, respectively. 1162ac27a0ecSDave Kleikamp * 1163ac27a0ecSDave Kleikamp * Returns 0, or a negative error number on failure. 1164ac27a0ecSDave Kleikamp */ 1165ac27a0ecSDave Kleikamp int 1166617ba13bSMingming Cao ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index, 1167ac27a0ecSDave Kleikamp const char *name, const void *value, size_t value_len, 1168ac27a0ecSDave Kleikamp int flags) 1169ac27a0ecSDave Kleikamp { 1170617ba13bSMingming Cao struct ext4_xattr_info i = { 1171ac27a0ecSDave Kleikamp .name_index = name_index, 1172ac27a0ecSDave Kleikamp .name = name, 1173ac27a0ecSDave Kleikamp .value = value, 1174ac27a0ecSDave Kleikamp .value_len = value_len, 1175ac27a0ecSDave Kleikamp 1176ac27a0ecSDave Kleikamp }; 1177617ba13bSMingming Cao struct ext4_xattr_ibody_find is = { 1178ac27a0ecSDave Kleikamp .s = { .not_found = -ENODATA, }, 1179ac27a0ecSDave Kleikamp }; 1180617ba13bSMingming Cao struct ext4_xattr_block_find bs = { 1181ac27a0ecSDave Kleikamp .s = { .not_found = -ENODATA, }, 1182ac27a0ecSDave Kleikamp }; 11834d20c685SKalpak Shah unsigned long no_expand; 1184ac27a0ecSDave Kleikamp int error; 1185ac27a0ecSDave Kleikamp 1186ac27a0ecSDave Kleikamp if (!name) 1187ac27a0ecSDave Kleikamp return -EINVAL; 1188ac27a0ecSDave Kleikamp if (strlen(name) > 255) 1189ac27a0ecSDave Kleikamp return -ERANGE; 1190617ba13bSMingming Cao down_write(&EXT4_I(inode)->xattr_sem); 119119f5fb7aSTheodore Ts'o no_expand = ext4_test_inode_state(inode, EXT4_STATE_NO_EXPAND); 119219f5fb7aSTheodore Ts'o ext4_set_inode_state(inode, EXT4_STATE_NO_EXPAND); 11934d20c685SKalpak Shah 119466543617SEric Sandeen error = ext4_reserve_inode_write(handle, inode, &is.iloc); 119586ebfd08SEric Sandeen if (error) 119686ebfd08SEric Sandeen goto cleanup; 119786ebfd08SEric Sandeen 119819f5fb7aSTheodore Ts'o if (ext4_test_inode_state(inode, EXT4_STATE_NEW)) { 1199617ba13bSMingming Cao struct ext4_inode *raw_inode = ext4_raw_inode(&is.iloc); 1200617ba13bSMingming Cao memset(raw_inode, 0, EXT4_SB(inode->i_sb)->s_inode_size); 120119f5fb7aSTheodore Ts'o ext4_clear_inode_state(inode, EXT4_STATE_NEW); 1202ac27a0ecSDave Kleikamp } 1203ac27a0ecSDave Kleikamp 1204617ba13bSMingming Cao error = ext4_xattr_ibody_find(inode, &i, &is); 1205ac27a0ecSDave Kleikamp if (error) 1206ac27a0ecSDave Kleikamp goto cleanup; 1207ac27a0ecSDave Kleikamp if (is.s.not_found) 1208617ba13bSMingming Cao error = ext4_xattr_block_find(inode, &i, &bs); 1209ac27a0ecSDave Kleikamp if (error) 1210ac27a0ecSDave Kleikamp goto cleanup; 1211ac27a0ecSDave Kleikamp if (is.s.not_found && bs.s.not_found) { 1212ac27a0ecSDave Kleikamp error = -ENODATA; 1213ac27a0ecSDave Kleikamp if (flags & XATTR_REPLACE) 1214ac27a0ecSDave Kleikamp goto cleanup; 1215ac27a0ecSDave Kleikamp error = 0; 1216ac27a0ecSDave Kleikamp if (!value) 1217ac27a0ecSDave Kleikamp goto cleanup; 1218ac27a0ecSDave Kleikamp } else { 1219ac27a0ecSDave Kleikamp error = -EEXIST; 1220ac27a0ecSDave Kleikamp if (flags & XATTR_CREATE) 1221ac27a0ecSDave Kleikamp goto cleanup; 1222ac27a0ecSDave Kleikamp } 1223ac27a0ecSDave Kleikamp if (!value) { 1224ac27a0ecSDave Kleikamp if (!is.s.not_found) 1225617ba13bSMingming Cao error = ext4_xattr_ibody_set(handle, inode, &i, &is); 1226ac27a0ecSDave Kleikamp else if (!bs.s.not_found) 1227617ba13bSMingming Cao error = ext4_xattr_block_set(handle, inode, &i, &bs); 1228ac27a0ecSDave Kleikamp } else { 12293fd16462SJan Kara error = 0; 12303fd16462SJan Kara /* Xattr value did not change? Save us some work and bail out */ 12313fd16462SJan Kara if (!is.s.not_found && ext4_xattr_value_same(&is.s, &i)) 12323fd16462SJan Kara goto cleanup; 12333fd16462SJan Kara if (!bs.s.not_found && ext4_xattr_value_same(&bs.s, &i)) 12343fd16462SJan Kara goto cleanup; 12353fd16462SJan Kara 1236617ba13bSMingming Cao error = ext4_xattr_ibody_set(handle, inode, &i, &is); 1237ac27a0ecSDave Kleikamp if (!error && !bs.s.not_found) { 1238ac27a0ecSDave Kleikamp i.value = NULL; 1239617ba13bSMingming Cao error = ext4_xattr_block_set(handle, inode, &i, &bs); 1240ac27a0ecSDave Kleikamp } else if (error == -ENOSPC) { 12417e01c8e5STiger Yang if (EXT4_I(inode)->i_file_acl && !bs.s.base) { 12427e01c8e5STiger Yang error = ext4_xattr_block_find(inode, &i, &bs); 12437e01c8e5STiger Yang if (error) 12447e01c8e5STiger Yang goto cleanup; 12457e01c8e5STiger Yang } 1246617ba13bSMingming Cao error = ext4_xattr_block_set(handle, inode, &i, &bs); 1247ac27a0ecSDave Kleikamp if (error) 1248ac27a0ecSDave Kleikamp goto cleanup; 1249ac27a0ecSDave Kleikamp if (!is.s.not_found) { 1250ac27a0ecSDave Kleikamp i.value = NULL; 1251617ba13bSMingming Cao error = ext4_xattr_ibody_set(handle, inode, &i, 1252ac27a0ecSDave Kleikamp &is); 1253ac27a0ecSDave Kleikamp } 1254ac27a0ecSDave Kleikamp } 1255ac27a0ecSDave Kleikamp } 1256ac27a0ecSDave Kleikamp if (!error) { 1257617ba13bSMingming Cao ext4_xattr_update_super_block(handle, inode->i_sb); 1258ef7f3835SKalpak Shah inode->i_ctime = ext4_current_time(inode); 12596dd4ee7cSKalpak Shah if (!value) 126019f5fb7aSTheodore Ts'o ext4_clear_inode_state(inode, EXT4_STATE_NO_EXPAND); 1261617ba13bSMingming Cao error = ext4_mark_iloc_dirty(handle, inode, &is.iloc); 1262ac27a0ecSDave Kleikamp /* 1263617ba13bSMingming Cao * The bh is consumed by ext4_mark_iloc_dirty, even with 1264ac27a0ecSDave Kleikamp * error != 0. 1265ac27a0ecSDave Kleikamp */ 1266ac27a0ecSDave Kleikamp is.iloc.bh = NULL; 1267ac27a0ecSDave Kleikamp if (IS_SYNC(inode)) 12680390131bSFrank Mayhar ext4_handle_sync(handle); 1269ac27a0ecSDave Kleikamp } 1270ac27a0ecSDave Kleikamp 1271ac27a0ecSDave Kleikamp cleanup: 1272ac27a0ecSDave Kleikamp brelse(is.iloc.bh); 1273ac27a0ecSDave Kleikamp brelse(bs.bh); 12744d20c685SKalpak Shah if (no_expand == 0) 127519f5fb7aSTheodore Ts'o ext4_clear_inode_state(inode, EXT4_STATE_NO_EXPAND); 1276617ba13bSMingming Cao up_write(&EXT4_I(inode)->xattr_sem); 1277ac27a0ecSDave Kleikamp return error; 1278ac27a0ecSDave Kleikamp } 1279ac27a0ecSDave Kleikamp 1280ac27a0ecSDave Kleikamp /* 1281617ba13bSMingming Cao * ext4_xattr_set() 1282ac27a0ecSDave Kleikamp * 1283617ba13bSMingming Cao * Like ext4_xattr_set_handle, but start from an inode. This extended 1284ac27a0ecSDave Kleikamp * attribute modification is a filesystem transaction by itself. 1285ac27a0ecSDave Kleikamp * 1286ac27a0ecSDave Kleikamp * Returns 0, or a negative error number on failure. 1287ac27a0ecSDave Kleikamp */ 1288ac27a0ecSDave Kleikamp int 1289617ba13bSMingming Cao ext4_xattr_set(struct inode *inode, int name_index, const char *name, 1290ac27a0ecSDave Kleikamp const void *value, size_t value_len, int flags) 1291ac27a0ecSDave Kleikamp { 1292ac27a0ecSDave Kleikamp handle_t *handle; 1293ac27a0ecSDave Kleikamp int error, retries = 0; 129495eaefbdSTheodore Ts'o int credits = ext4_jbd2_credits_xattr(inode); 1295ac27a0ecSDave Kleikamp 1296ac27a0ecSDave Kleikamp retry: 12979924a92aSTheodore Ts'o handle = ext4_journal_start(inode, EXT4_HT_XATTR, credits); 1298ac27a0ecSDave Kleikamp if (IS_ERR(handle)) { 1299ac27a0ecSDave Kleikamp error = PTR_ERR(handle); 1300ac27a0ecSDave Kleikamp } else { 1301ac27a0ecSDave Kleikamp int error2; 1302ac27a0ecSDave Kleikamp 1303617ba13bSMingming Cao error = ext4_xattr_set_handle(handle, inode, name_index, name, 1304ac27a0ecSDave Kleikamp value, value_len, flags); 1305617ba13bSMingming Cao error2 = ext4_journal_stop(handle); 1306ac27a0ecSDave Kleikamp if (error == -ENOSPC && 1307617ba13bSMingming Cao ext4_should_retry_alloc(inode->i_sb, &retries)) 1308ac27a0ecSDave Kleikamp goto retry; 1309ac27a0ecSDave Kleikamp if (error == 0) 1310ac27a0ecSDave Kleikamp error = error2; 1311ac27a0ecSDave Kleikamp } 1312ac27a0ecSDave Kleikamp 1313ac27a0ecSDave Kleikamp return error; 1314ac27a0ecSDave Kleikamp } 1315ac27a0ecSDave Kleikamp 1316ac27a0ecSDave Kleikamp /* 13176dd4ee7cSKalpak Shah * Shift the EA entries in the inode to create space for the increased 13186dd4ee7cSKalpak Shah * i_extra_isize. 13196dd4ee7cSKalpak Shah */ 13206dd4ee7cSKalpak Shah static void ext4_xattr_shift_entries(struct ext4_xattr_entry *entry, 13216dd4ee7cSKalpak Shah int value_offs_shift, void *to, 132294405713SJan Kara void *from, size_t n) 13236dd4ee7cSKalpak Shah { 13246dd4ee7cSKalpak Shah struct ext4_xattr_entry *last = entry; 13256dd4ee7cSKalpak Shah int new_offs; 13266dd4ee7cSKalpak Shah 132794405713SJan Kara /* We always shift xattr headers further thus offsets get lower */ 132894405713SJan Kara BUG_ON(value_offs_shift > 0); 132994405713SJan Kara 13306dd4ee7cSKalpak Shah /* Adjust the value offsets of the entries */ 13316dd4ee7cSKalpak Shah for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { 13321cba4237SJan Kara if (last->e_value_size) { 13336dd4ee7cSKalpak Shah new_offs = le16_to_cpu(last->e_value_offs) + 13346dd4ee7cSKalpak Shah value_offs_shift; 13356dd4ee7cSKalpak Shah last->e_value_offs = cpu_to_le16(new_offs); 13366dd4ee7cSKalpak Shah } 13376dd4ee7cSKalpak Shah } 13386dd4ee7cSKalpak Shah /* Shift the entries by n bytes */ 13396dd4ee7cSKalpak Shah memmove(to, from, n); 13406dd4ee7cSKalpak Shah } 13416dd4ee7cSKalpak Shah 13426dd4ee7cSKalpak Shah /* 13433f2571c1SJan Kara * Move xattr pointed to by 'entry' from inode into external xattr block 13443f2571c1SJan Kara */ 13453f2571c1SJan Kara static int ext4_xattr_move_to_block(handle_t *handle, struct inode *inode, 13463f2571c1SJan Kara struct ext4_inode *raw_inode, 13473f2571c1SJan Kara struct ext4_xattr_entry *entry) 13483f2571c1SJan Kara { 13493f2571c1SJan Kara struct ext4_xattr_ibody_find *is = NULL; 13503f2571c1SJan Kara struct ext4_xattr_block_find *bs = NULL; 13513f2571c1SJan Kara char *buffer = NULL, *b_entry_name = NULL; 13523f2571c1SJan Kara size_t value_offs, value_size; 13533f2571c1SJan Kara struct ext4_xattr_info i = { 13543f2571c1SJan Kara .value = NULL, 13553f2571c1SJan Kara .value_len = 0, 13563f2571c1SJan Kara .name_index = entry->e_name_index, 13573f2571c1SJan Kara }; 13583f2571c1SJan Kara struct ext4_xattr_ibody_header *header = IHDR(inode, raw_inode); 13593f2571c1SJan Kara int error; 13603f2571c1SJan Kara 13613f2571c1SJan Kara value_offs = le16_to_cpu(entry->e_value_offs); 13623f2571c1SJan Kara value_size = le32_to_cpu(entry->e_value_size); 13633f2571c1SJan Kara 13643f2571c1SJan Kara is = kzalloc(sizeof(struct ext4_xattr_ibody_find), GFP_NOFS); 13653f2571c1SJan Kara bs = kzalloc(sizeof(struct ext4_xattr_block_find), GFP_NOFS); 13663f2571c1SJan Kara buffer = kmalloc(value_size, GFP_NOFS); 13673f2571c1SJan Kara b_entry_name = kmalloc(entry->e_name_len + 1, GFP_NOFS); 13683f2571c1SJan Kara if (!is || !bs || !buffer || !b_entry_name) { 13693f2571c1SJan Kara error = -ENOMEM; 13703f2571c1SJan Kara goto out; 13713f2571c1SJan Kara } 13723f2571c1SJan Kara 13733f2571c1SJan Kara is->s.not_found = -ENODATA; 13743f2571c1SJan Kara bs->s.not_found = -ENODATA; 13753f2571c1SJan Kara is->iloc.bh = NULL; 13763f2571c1SJan Kara bs->bh = NULL; 13773f2571c1SJan Kara 13783f2571c1SJan Kara /* Save the entry name and the entry value */ 13793f2571c1SJan Kara memcpy(buffer, (void *)IFIRST(header) + value_offs, value_size); 13803f2571c1SJan Kara memcpy(b_entry_name, entry->e_name, entry->e_name_len); 13813f2571c1SJan Kara b_entry_name[entry->e_name_len] = '\0'; 13823f2571c1SJan Kara i.name = b_entry_name; 13833f2571c1SJan Kara 13843f2571c1SJan Kara error = ext4_get_inode_loc(inode, &is->iloc); 13853f2571c1SJan Kara if (error) 13863f2571c1SJan Kara goto out; 13873f2571c1SJan Kara 13883f2571c1SJan Kara error = ext4_xattr_ibody_find(inode, &i, is); 13893f2571c1SJan Kara if (error) 13903f2571c1SJan Kara goto out; 13913f2571c1SJan Kara 13923f2571c1SJan Kara /* Remove the chosen entry from the inode */ 13933f2571c1SJan Kara error = ext4_xattr_ibody_set(handle, inode, &i, is); 13943f2571c1SJan Kara if (error) 13953f2571c1SJan Kara goto out; 13963f2571c1SJan Kara 13973f2571c1SJan Kara i.name = b_entry_name; 13983f2571c1SJan Kara i.value = buffer; 13993f2571c1SJan Kara i.value_len = value_size; 14003f2571c1SJan Kara error = ext4_xattr_block_find(inode, &i, bs); 14013f2571c1SJan Kara if (error) 14023f2571c1SJan Kara goto out; 14033f2571c1SJan Kara 14043f2571c1SJan Kara /* Add entry which was removed from the inode into the block */ 14053f2571c1SJan Kara error = ext4_xattr_block_set(handle, inode, &i, bs); 14063f2571c1SJan Kara if (error) 14073f2571c1SJan Kara goto out; 14083f2571c1SJan Kara error = 0; 14093f2571c1SJan Kara out: 14103f2571c1SJan Kara kfree(b_entry_name); 14113f2571c1SJan Kara kfree(buffer); 14123f2571c1SJan Kara if (is) 14133f2571c1SJan Kara brelse(is->iloc.bh); 14143f2571c1SJan Kara kfree(is); 14153f2571c1SJan Kara kfree(bs); 14163f2571c1SJan Kara 14173f2571c1SJan Kara return error; 14183f2571c1SJan Kara } 14193f2571c1SJan Kara 1420dfa2064bSJan Kara static int ext4_xattr_make_inode_space(handle_t *handle, struct inode *inode, 1421dfa2064bSJan Kara struct ext4_inode *raw_inode, 1422dfa2064bSJan Kara int isize_diff, size_t ifree, 1423dfa2064bSJan Kara size_t bfree, int *total_ino) 1424dfa2064bSJan Kara { 1425dfa2064bSJan Kara struct ext4_xattr_ibody_header *header = IHDR(inode, raw_inode); 1426dfa2064bSJan Kara struct ext4_xattr_entry *small_entry; 1427dfa2064bSJan Kara struct ext4_xattr_entry *entry; 1428dfa2064bSJan Kara struct ext4_xattr_entry *last; 1429dfa2064bSJan Kara unsigned int entry_size; /* EA entry size */ 1430dfa2064bSJan Kara unsigned int total_size; /* EA entry size + value size */ 1431dfa2064bSJan Kara unsigned int min_total_size; 1432dfa2064bSJan Kara int error; 1433dfa2064bSJan Kara 1434dfa2064bSJan Kara while (isize_diff > ifree) { 1435dfa2064bSJan Kara entry = NULL; 1436dfa2064bSJan Kara small_entry = NULL; 1437dfa2064bSJan Kara min_total_size = ~0U; 1438dfa2064bSJan Kara last = IFIRST(header); 1439dfa2064bSJan Kara /* Find the entry best suited to be pushed into EA block */ 1440dfa2064bSJan Kara for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { 1441dfa2064bSJan Kara total_size = 1442dfa2064bSJan Kara EXT4_XATTR_SIZE(le32_to_cpu(last->e_value_size)) + 1443dfa2064bSJan Kara EXT4_XATTR_LEN(last->e_name_len); 1444dfa2064bSJan Kara if (total_size <= bfree && 1445dfa2064bSJan Kara total_size < min_total_size) { 1446dfa2064bSJan Kara if (total_size + ifree < isize_diff) { 1447dfa2064bSJan Kara small_entry = last; 1448dfa2064bSJan Kara } else { 1449dfa2064bSJan Kara entry = last; 1450dfa2064bSJan Kara min_total_size = total_size; 1451dfa2064bSJan Kara } 1452dfa2064bSJan Kara } 1453dfa2064bSJan Kara } 1454dfa2064bSJan Kara 1455dfa2064bSJan Kara if (entry == NULL) { 1456dfa2064bSJan Kara if (small_entry == NULL) 1457dfa2064bSJan Kara return -ENOSPC; 1458dfa2064bSJan Kara entry = small_entry; 1459dfa2064bSJan Kara } 1460dfa2064bSJan Kara 1461dfa2064bSJan Kara entry_size = EXT4_XATTR_LEN(entry->e_name_len); 1462dfa2064bSJan Kara total_size = entry_size + 1463dfa2064bSJan Kara EXT4_XATTR_SIZE(le32_to_cpu(entry->e_value_size)); 1464dfa2064bSJan Kara error = ext4_xattr_move_to_block(handle, inode, raw_inode, 1465dfa2064bSJan Kara entry); 1466dfa2064bSJan Kara if (error) 1467dfa2064bSJan Kara return error; 1468dfa2064bSJan Kara 1469dfa2064bSJan Kara *total_ino -= entry_size; 1470dfa2064bSJan Kara ifree += total_size; 1471dfa2064bSJan Kara bfree -= total_size; 1472dfa2064bSJan Kara } 1473dfa2064bSJan Kara 1474dfa2064bSJan Kara return 0; 1475dfa2064bSJan Kara } 1476dfa2064bSJan Kara 14773f2571c1SJan Kara /* 14786dd4ee7cSKalpak Shah * Expand an inode by new_extra_isize bytes when EAs are present. 14796dd4ee7cSKalpak Shah * Returns 0 on success or negative error number on failure. 14806dd4ee7cSKalpak Shah */ 14816dd4ee7cSKalpak Shah int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize, 14826dd4ee7cSKalpak Shah struct ext4_inode *raw_inode, handle_t *handle) 14836dd4ee7cSKalpak Shah { 14846dd4ee7cSKalpak Shah struct ext4_xattr_ibody_header *header; 14856dd4ee7cSKalpak Shah struct buffer_head *bh = NULL; 1486e3014d14SJan Kara size_t min_offs; 1487e3014d14SJan Kara size_t ifree, bfree; 14887b1b2c1bSTheodore Ts'o int total_ino; 14896e0cd088SJan Kara void *base, *end; 1490d0141191SJan Kara int error = 0, tried_min_extra_isize = 0; 1491ac39849dSAneesh Kumar K.V int s_min_extra_isize = le16_to_cpu(EXT4_SB(inode->i_sb)->s_es->s_min_extra_isize); 1492d0141191SJan Kara int isize_diff; /* How much do we need to grow i_extra_isize */ 14936dd4ee7cSKalpak Shah 14946dd4ee7cSKalpak Shah down_write(&EXT4_I(inode)->xattr_sem); 14952e81a4eeSJan Kara /* 14962e81a4eeSJan Kara * Set EXT4_STATE_NO_EXPAND to avoid recursion when marking inode dirty 14972e81a4eeSJan Kara */ 14982e81a4eeSJan Kara ext4_set_inode_state(inode, EXT4_STATE_NO_EXPAND); 14996dd4ee7cSKalpak Shah retry: 1500d0141191SJan Kara isize_diff = new_extra_isize - EXT4_I(inode)->i_extra_isize; 15012e81a4eeSJan Kara if (EXT4_I(inode)->i_extra_isize >= new_extra_isize) 15022e81a4eeSJan Kara goto out; 15036dd4ee7cSKalpak Shah 15046dd4ee7cSKalpak Shah header = IHDR(inode, raw_inode); 15056dd4ee7cSKalpak Shah 15066dd4ee7cSKalpak Shah /* 15076dd4ee7cSKalpak Shah * Check if enough free space is available in the inode to shift the 15086dd4ee7cSKalpak Shah * entries ahead by new_extra_isize. 15096dd4ee7cSKalpak Shah */ 15106dd4ee7cSKalpak Shah 15116e0cd088SJan Kara base = IFIRST(header); 15126dd4ee7cSKalpak Shah end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; 15136dd4ee7cSKalpak Shah min_offs = end - base; 15146dd4ee7cSKalpak Shah total_ino = sizeof(struct ext4_xattr_ibody_header); 15156dd4ee7cSKalpak Shah 15169e92f48cSTheodore Ts'o error = xattr_check_inode(inode, header, end); 15179e92f48cSTheodore Ts'o if (error) 15189e92f48cSTheodore Ts'o goto cleanup; 15199e92f48cSTheodore Ts'o 15206e0cd088SJan Kara ifree = ext4_xattr_free_space(base, &min_offs, base, &total_ino); 1521e3014d14SJan Kara if (ifree >= isize_diff) 1522e3014d14SJan Kara goto shift; 15236dd4ee7cSKalpak Shah 15246dd4ee7cSKalpak Shah /* 15256dd4ee7cSKalpak Shah * Enough free space isn't available in the inode, check if 15266dd4ee7cSKalpak Shah * EA block can hold new_extra_isize bytes. 15276dd4ee7cSKalpak Shah */ 15286dd4ee7cSKalpak Shah if (EXT4_I(inode)->i_file_acl) { 15296dd4ee7cSKalpak Shah bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); 15306dd4ee7cSKalpak Shah error = -EIO; 15316dd4ee7cSKalpak Shah if (!bh) 15326dd4ee7cSKalpak Shah goto cleanup; 1533cc8e94fdSDarrick J. Wong if (ext4_xattr_check_block(inode, bh)) { 153424676da4STheodore Ts'o EXT4_ERROR_INODE(inode, "bad block %llu", 153524676da4STheodore Ts'o EXT4_I(inode)->i_file_acl); 15366a797d27SDarrick J. Wong error = -EFSCORRUPTED; 15376dd4ee7cSKalpak Shah goto cleanup; 15386dd4ee7cSKalpak Shah } 15396dd4ee7cSKalpak Shah base = BHDR(bh); 15406dd4ee7cSKalpak Shah end = bh->b_data + bh->b_size; 15416dd4ee7cSKalpak Shah min_offs = end - base; 15426e0cd088SJan Kara bfree = ext4_xattr_free_space(BFIRST(bh), &min_offs, base, 15436e0cd088SJan Kara NULL); 1544e3014d14SJan Kara if (bfree + ifree < isize_diff) { 15456dd4ee7cSKalpak Shah if (!tried_min_extra_isize && s_min_extra_isize) { 15466dd4ee7cSKalpak Shah tried_min_extra_isize++; 15476dd4ee7cSKalpak Shah new_extra_isize = s_min_extra_isize; 15486dd4ee7cSKalpak Shah brelse(bh); 15496dd4ee7cSKalpak Shah goto retry; 15506dd4ee7cSKalpak Shah } 1551dfa2064bSJan Kara error = -ENOSPC; 15526dd4ee7cSKalpak Shah goto cleanup; 15536dd4ee7cSKalpak Shah } 15546dd4ee7cSKalpak Shah } else { 1555e3014d14SJan Kara bfree = inode->i_sb->s_blocksize; 15566dd4ee7cSKalpak Shah } 15576dd4ee7cSKalpak Shah 1558dfa2064bSJan Kara error = ext4_xattr_make_inode_space(handle, inode, raw_inode, 1559dfa2064bSJan Kara isize_diff, ifree, bfree, 1560dfa2064bSJan Kara &total_ino); 1561dfa2064bSJan Kara if (error) { 1562dfa2064bSJan Kara if (error == -ENOSPC && !tried_min_extra_isize && 15636dd4ee7cSKalpak Shah s_min_extra_isize) { 15646dd4ee7cSKalpak Shah tried_min_extra_isize++; 15656dd4ee7cSKalpak Shah new_extra_isize = s_min_extra_isize; 1566dcb9917bSTheodore Ts'o brelse(bh); 15676dd4ee7cSKalpak Shah goto retry; 15686dd4ee7cSKalpak Shah } 15696dd4ee7cSKalpak Shah goto cleanup; 15706dd4ee7cSKalpak Shah } 1571e3014d14SJan Kara shift: 1572e3014d14SJan Kara /* Adjust the offsets and shift the remaining entries ahead */ 15736e0cd088SJan Kara ext4_xattr_shift_entries(IFIRST(header), EXT4_I(inode)->i_extra_isize 1574e3014d14SJan Kara - new_extra_isize, (void *)raw_inode + 1575e3014d14SJan Kara EXT4_GOOD_OLD_INODE_SIZE + new_extra_isize, 157694405713SJan Kara (void *)header, total_ino); 1577e3014d14SJan Kara EXT4_I(inode)->i_extra_isize = new_extra_isize; 15786dd4ee7cSKalpak Shah brelse(bh); 15792e81a4eeSJan Kara out: 15802e81a4eeSJan Kara ext4_clear_inode_state(inode, EXT4_STATE_NO_EXPAND); 15816dd4ee7cSKalpak Shah up_write(&EXT4_I(inode)->xattr_sem); 15826dd4ee7cSKalpak Shah return 0; 15836dd4ee7cSKalpak Shah 15846dd4ee7cSKalpak Shah cleanup: 15856dd4ee7cSKalpak Shah brelse(bh); 15862e81a4eeSJan Kara /* 15872e81a4eeSJan Kara * We deliberately leave EXT4_STATE_NO_EXPAND set here since inode 15882e81a4eeSJan Kara * size expansion failed. 15892e81a4eeSJan Kara */ 15906dd4ee7cSKalpak Shah up_write(&EXT4_I(inode)->xattr_sem); 15916dd4ee7cSKalpak Shah return error; 15926dd4ee7cSKalpak Shah } 15936dd4ee7cSKalpak Shah 15946dd4ee7cSKalpak Shah 15956dd4ee7cSKalpak Shah 15966dd4ee7cSKalpak Shah /* 1597617ba13bSMingming Cao * ext4_xattr_delete_inode() 1598ac27a0ecSDave Kleikamp * 1599ac27a0ecSDave Kleikamp * Free extended attribute resources associated with this inode. This 1600ac27a0ecSDave Kleikamp * is called immediately before an inode is freed. We have exclusive 1601ac27a0ecSDave Kleikamp * access to the inode. 1602ac27a0ecSDave Kleikamp */ 1603ac27a0ecSDave Kleikamp void 1604617ba13bSMingming Cao ext4_xattr_delete_inode(handle_t *handle, struct inode *inode) 1605ac27a0ecSDave Kleikamp { 1606ac27a0ecSDave Kleikamp struct buffer_head *bh = NULL; 1607ac27a0ecSDave Kleikamp 1608617ba13bSMingming Cao if (!EXT4_I(inode)->i_file_acl) 1609ac27a0ecSDave Kleikamp goto cleanup; 1610617ba13bSMingming Cao bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); 1611ac27a0ecSDave Kleikamp if (!bh) { 161224676da4STheodore Ts'o EXT4_ERROR_INODE(inode, "block %llu read error", 161324676da4STheodore Ts'o EXT4_I(inode)->i_file_acl); 1614ac27a0ecSDave Kleikamp goto cleanup; 1615ac27a0ecSDave Kleikamp } 1616617ba13bSMingming Cao if (BHDR(bh)->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC) || 1617ac27a0ecSDave Kleikamp BHDR(bh)->h_blocks != cpu_to_le32(1)) { 161824676da4STheodore Ts'o EXT4_ERROR_INODE(inode, "bad block %llu", 161924676da4STheodore Ts'o EXT4_I(inode)->i_file_acl); 1620ac27a0ecSDave Kleikamp goto cleanup; 1621ac27a0ecSDave Kleikamp } 1622617ba13bSMingming Cao ext4_xattr_release_block(handle, inode, bh); 1623617ba13bSMingming Cao EXT4_I(inode)->i_file_acl = 0; 1624ac27a0ecSDave Kleikamp 1625ac27a0ecSDave Kleikamp cleanup: 1626ac27a0ecSDave Kleikamp brelse(bh); 1627ac27a0ecSDave Kleikamp } 1628ac27a0ecSDave Kleikamp 1629ac27a0ecSDave Kleikamp /* 1630617ba13bSMingming Cao * ext4_xattr_cache_insert() 1631ac27a0ecSDave Kleikamp * 1632ac27a0ecSDave Kleikamp * Create a new entry in the extended attribute cache, and insert 1633ac27a0ecSDave Kleikamp * it unless such an entry is already in the cache. 1634ac27a0ecSDave Kleikamp * 1635ac27a0ecSDave Kleikamp * Returns 0, or a negative error number on failure. 1636ac27a0ecSDave Kleikamp */ 1637ac27a0ecSDave Kleikamp static void 16387a2508e1SJan Kara ext4_xattr_cache_insert(struct mb_cache *ext4_mb_cache, struct buffer_head *bh) 1639ac27a0ecSDave Kleikamp { 16406048c64bSAndreas Gruenbacher struct ext4_xattr_header *header = BHDR(bh); 16416048c64bSAndreas Gruenbacher __u32 hash = le32_to_cpu(header->h_hash); 16426048c64bSAndreas Gruenbacher int reusable = le32_to_cpu(header->h_refcount) < 16436048c64bSAndreas Gruenbacher EXT4_XATTR_REFCOUNT_MAX; 1644ac27a0ecSDave Kleikamp int error; 1645ac27a0ecSDave Kleikamp 16467a2508e1SJan Kara error = mb_cache_entry_create(ext4_mb_cache, GFP_NOFS, hash, 16476048c64bSAndreas Gruenbacher bh->b_blocknr, reusable); 1648ac27a0ecSDave Kleikamp if (error) { 164982939d79SJan Kara if (error == -EBUSY) 1650ac27a0ecSDave Kleikamp ea_bdebug(bh, "already in cache"); 165182939d79SJan Kara } else 1652ac27a0ecSDave Kleikamp ea_bdebug(bh, "inserting [%x]", (int)hash); 1653ac27a0ecSDave Kleikamp } 1654ac27a0ecSDave Kleikamp 1655ac27a0ecSDave Kleikamp /* 1656617ba13bSMingming Cao * ext4_xattr_cmp() 1657ac27a0ecSDave Kleikamp * 1658ac27a0ecSDave Kleikamp * Compare two extended attribute blocks for equality. 1659ac27a0ecSDave Kleikamp * 1660ac27a0ecSDave Kleikamp * Returns 0 if the blocks are equal, 1 if they differ, and 1661ac27a0ecSDave Kleikamp * a negative error number on errors. 1662ac27a0ecSDave Kleikamp */ 1663ac27a0ecSDave Kleikamp static int 1664617ba13bSMingming Cao ext4_xattr_cmp(struct ext4_xattr_header *header1, 1665617ba13bSMingming Cao struct ext4_xattr_header *header2) 1666ac27a0ecSDave Kleikamp { 1667617ba13bSMingming Cao struct ext4_xattr_entry *entry1, *entry2; 1668ac27a0ecSDave Kleikamp 1669ac27a0ecSDave Kleikamp entry1 = ENTRY(header1+1); 1670ac27a0ecSDave Kleikamp entry2 = ENTRY(header2+1); 1671ac27a0ecSDave Kleikamp while (!IS_LAST_ENTRY(entry1)) { 1672ac27a0ecSDave Kleikamp if (IS_LAST_ENTRY(entry2)) 1673ac27a0ecSDave Kleikamp return 1; 1674ac27a0ecSDave Kleikamp if (entry1->e_hash != entry2->e_hash || 1675ac27a0ecSDave Kleikamp entry1->e_name_index != entry2->e_name_index || 1676ac27a0ecSDave Kleikamp entry1->e_name_len != entry2->e_name_len || 1677ac27a0ecSDave Kleikamp entry1->e_value_size != entry2->e_value_size || 1678ac27a0ecSDave Kleikamp memcmp(entry1->e_name, entry2->e_name, entry1->e_name_len)) 1679ac27a0ecSDave Kleikamp return 1; 1680ac27a0ecSDave Kleikamp if (entry1->e_value_block != 0 || entry2->e_value_block != 0) 16816a797d27SDarrick J. Wong return -EFSCORRUPTED; 1682ac27a0ecSDave Kleikamp if (memcmp((char *)header1 + le16_to_cpu(entry1->e_value_offs), 1683ac27a0ecSDave Kleikamp (char *)header2 + le16_to_cpu(entry2->e_value_offs), 1684ac27a0ecSDave Kleikamp le32_to_cpu(entry1->e_value_size))) 1685ac27a0ecSDave Kleikamp return 1; 1686ac27a0ecSDave Kleikamp 1687617ba13bSMingming Cao entry1 = EXT4_XATTR_NEXT(entry1); 1688617ba13bSMingming Cao entry2 = EXT4_XATTR_NEXT(entry2); 1689ac27a0ecSDave Kleikamp } 1690ac27a0ecSDave Kleikamp if (!IS_LAST_ENTRY(entry2)) 1691ac27a0ecSDave Kleikamp return 1; 1692ac27a0ecSDave Kleikamp return 0; 1693ac27a0ecSDave Kleikamp } 1694ac27a0ecSDave Kleikamp 1695ac27a0ecSDave Kleikamp /* 1696617ba13bSMingming Cao * ext4_xattr_cache_find() 1697ac27a0ecSDave Kleikamp * 1698ac27a0ecSDave Kleikamp * Find an identical extended attribute block. 1699ac27a0ecSDave Kleikamp * 1700ac27a0ecSDave Kleikamp * Returns a pointer to the block found, or NULL if such a block was 1701ac27a0ecSDave Kleikamp * not found or an error occurred. 1702ac27a0ecSDave Kleikamp */ 1703ac27a0ecSDave Kleikamp static struct buffer_head * 1704617ba13bSMingming Cao ext4_xattr_cache_find(struct inode *inode, struct ext4_xattr_header *header, 17057a2508e1SJan Kara struct mb_cache_entry **pce) 1706ac27a0ecSDave Kleikamp { 1707ac27a0ecSDave Kleikamp __u32 hash = le32_to_cpu(header->h_hash); 17087a2508e1SJan Kara struct mb_cache_entry *ce; 17097a2508e1SJan Kara struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); 1710ac27a0ecSDave Kleikamp 1711ac27a0ecSDave Kleikamp if (!header->h_hash) 1712ac27a0ecSDave Kleikamp return NULL; /* never share */ 1713ac27a0ecSDave Kleikamp ea_idebug(inode, "looking for cached blocks [%x]", (int)hash); 17147a2508e1SJan Kara ce = mb_cache_entry_find_first(ext4_mb_cache, hash); 1715ac27a0ecSDave Kleikamp while (ce) { 1716ac27a0ecSDave Kleikamp struct buffer_head *bh; 1717ac27a0ecSDave Kleikamp 1718ac27a0ecSDave Kleikamp bh = sb_bread(inode->i_sb, ce->e_block); 1719ac27a0ecSDave Kleikamp if (!bh) { 172024676da4STheodore Ts'o EXT4_ERROR_INODE(inode, "block %lu read error", 172124676da4STheodore Ts'o (unsigned long) ce->e_block); 1722617ba13bSMingming Cao } else if (ext4_xattr_cmp(header, BHDR(bh)) == 0) { 1723ac27a0ecSDave Kleikamp *pce = ce; 1724ac27a0ecSDave Kleikamp return bh; 1725ac27a0ecSDave Kleikamp } 1726ac27a0ecSDave Kleikamp brelse(bh); 17277a2508e1SJan Kara ce = mb_cache_entry_find_next(ext4_mb_cache, ce); 1728ac27a0ecSDave Kleikamp } 1729ac27a0ecSDave Kleikamp return NULL; 1730ac27a0ecSDave Kleikamp } 1731ac27a0ecSDave Kleikamp 1732ac27a0ecSDave Kleikamp #define NAME_HASH_SHIFT 5 1733ac27a0ecSDave Kleikamp #define VALUE_HASH_SHIFT 16 1734ac27a0ecSDave Kleikamp 1735ac27a0ecSDave Kleikamp /* 1736617ba13bSMingming Cao * ext4_xattr_hash_entry() 1737ac27a0ecSDave Kleikamp * 1738ac27a0ecSDave Kleikamp * Compute the hash of an extended attribute. 1739ac27a0ecSDave Kleikamp */ 1740617ba13bSMingming Cao static inline void ext4_xattr_hash_entry(struct ext4_xattr_header *header, 1741617ba13bSMingming Cao struct ext4_xattr_entry *entry) 1742ac27a0ecSDave Kleikamp { 1743ac27a0ecSDave Kleikamp __u32 hash = 0; 1744ac27a0ecSDave Kleikamp char *name = entry->e_name; 1745ac27a0ecSDave Kleikamp int n; 1746ac27a0ecSDave Kleikamp 1747ac27a0ecSDave Kleikamp for (n = 0; n < entry->e_name_len; n++) { 1748ac27a0ecSDave Kleikamp hash = (hash << NAME_HASH_SHIFT) ^ 1749ac27a0ecSDave Kleikamp (hash >> (8*sizeof(hash) - NAME_HASH_SHIFT)) ^ 1750ac27a0ecSDave Kleikamp *name++; 1751ac27a0ecSDave Kleikamp } 1752ac27a0ecSDave Kleikamp 17531cba4237SJan Kara if (entry->e_value_size != 0) { 1754ac27a0ecSDave Kleikamp __le32 *value = (__le32 *)((char *)header + 1755ac27a0ecSDave Kleikamp le16_to_cpu(entry->e_value_offs)); 1756ac27a0ecSDave Kleikamp for (n = (le32_to_cpu(entry->e_value_size) + 1757617ba13bSMingming Cao EXT4_XATTR_ROUND) >> EXT4_XATTR_PAD_BITS; n; n--) { 1758ac27a0ecSDave Kleikamp hash = (hash << VALUE_HASH_SHIFT) ^ 1759ac27a0ecSDave Kleikamp (hash >> (8*sizeof(hash) - VALUE_HASH_SHIFT)) ^ 1760ac27a0ecSDave Kleikamp le32_to_cpu(*value++); 1761ac27a0ecSDave Kleikamp } 1762ac27a0ecSDave Kleikamp } 1763ac27a0ecSDave Kleikamp entry->e_hash = cpu_to_le32(hash); 1764ac27a0ecSDave Kleikamp } 1765ac27a0ecSDave Kleikamp 1766ac27a0ecSDave Kleikamp #undef NAME_HASH_SHIFT 1767ac27a0ecSDave Kleikamp #undef VALUE_HASH_SHIFT 1768ac27a0ecSDave Kleikamp 1769ac27a0ecSDave Kleikamp #define BLOCK_HASH_SHIFT 16 1770ac27a0ecSDave Kleikamp 1771ac27a0ecSDave Kleikamp /* 1772617ba13bSMingming Cao * ext4_xattr_rehash() 1773ac27a0ecSDave Kleikamp * 1774ac27a0ecSDave Kleikamp * Re-compute the extended attribute hash value after an entry has changed. 1775ac27a0ecSDave Kleikamp */ 1776617ba13bSMingming Cao static void ext4_xattr_rehash(struct ext4_xattr_header *header, 1777617ba13bSMingming Cao struct ext4_xattr_entry *entry) 1778ac27a0ecSDave Kleikamp { 1779617ba13bSMingming Cao struct ext4_xattr_entry *here; 1780ac27a0ecSDave Kleikamp __u32 hash = 0; 1781ac27a0ecSDave Kleikamp 1782617ba13bSMingming Cao ext4_xattr_hash_entry(header, entry); 1783ac27a0ecSDave Kleikamp here = ENTRY(header+1); 1784ac27a0ecSDave Kleikamp while (!IS_LAST_ENTRY(here)) { 1785ac27a0ecSDave Kleikamp if (!here->e_hash) { 1786ac27a0ecSDave Kleikamp /* Block is not shared if an entry's hash value == 0 */ 1787ac27a0ecSDave Kleikamp hash = 0; 1788ac27a0ecSDave Kleikamp break; 1789ac27a0ecSDave Kleikamp } 1790ac27a0ecSDave Kleikamp hash = (hash << BLOCK_HASH_SHIFT) ^ 1791ac27a0ecSDave Kleikamp (hash >> (8*sizeof(hash) - BLOCK_HASH_SHIFT)) ^ 1792ac27a0ecSDave Kleikamp le32_to_cpu(here->e_hash); 1793617ba13bSMingming Cao here = EXT4_XATTR_NEXT(here); 1794ac27a0ecSDave Kleikamp } 1795ac27a0ecSDave Kleikamp header->h_hash = cpu_to_le32(hash); 1796ac27a0ecSDave Kleikamp } 1797ac27a0ecSDave Kleikamp 1798ac27a0ecSDave Kleikamp #undef BLOCK_HASH_SHIFT 1799ac27a0ecSDave Kleikamp 18009c191f70ST Makphaibulchoke #define HASH_BUCKET_BITS 10 18019c191f70ST Makphaibulchoke 18027a2508e1SJan Kara struct mb_cache * 180382939d79SJan Kara ext4_xattr_create_cache(void) 1804ac27a0ecSDave Kleikamp { 18057a2508e1SJan Kara return mb_cache_create(HASH_BUCKET_BITS); 1806ac27a0ecSDave Kleikamp } 1807ac27a0ecSDave Kleikamp 18087a2508e1SJan Kara void ext4_xattr_destroy_cache(struct mb_cache *cache) 1809ac27a0ecSDave Kleikamp { 18109c191f70ST Makphaibulchoke if (cache) 18117a2508e1SJan Kara mb_cache_destroy(cache); 1812ac27a0ecSDave Kleikamp } 18139c191f70ST Makphaibulchoke 1814