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 __le32 save_csum; 125d6a77105STheodore Ts'o __le64 dsk_block_nr = cpu_to_le64(block_nr); 126cc8e94fdSDarrick J. Wong 127d6a77105STheodore Ts'o save_csum = hdr->h_checksum; 128cc8e94fdSDarrick J. Wong hdr->h_checksum = 0; 129d6a77105STheodore Ts'o csum = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&dsk_block_nr, 130d6a77105STheodore Ts'o sizeof(dsk_block_nr)); 131cc8e94fdSDarrick J. Wong csum = ext4_chksum(sbi, csum, (__u8 *)hdr, 132cc8e94fdSDarrick J. Wong EXT4_BLOCK_SIZE(inode->i_sb)); 13341eb70ddSTao Ma 134d6a77105STheodore Ts'o hdr->h_checksum = save_csum; 135cc8e94fdSDarrick J. Wong return cpu_to_le32(csum); 136cc8e94fdSDarrick J. Wong } 137cc8e94fdSDarrick J. Wong 138cc8e94fdSDarrick J. Wong static int ext4_xattr_block_csum_verify(struct inode *inode, 139cc8e94fdSDarrick J. Wong sector_t block_nr, 140cc8e94fdSDarrick J. Wong struct ext4_xattr_header *hdr) 141cc8e94fdSDarrick J. Wong { 1429aa5d32bSDmitry Monakhov if (ext4_has_metadata_csum(inode->i_sb) && 143cc8e94fdSDarrick J. Wong (hdr->h_checksum != ext4_xattr_block_csum(inode, block_nr, hdr))) 144cc8e94fdSDarrick J. Wong return 0; 145cc8e94fdSDarrick J. Wong return 1; 146cc8e94fdSDarrick J. Wong } 147cc8e94fdSDarrick J. Wong 148cc8e94fdSDarrick J. Wong static void ext4_xattr_block_csum_set(struct inode *inode, 149cc8e94fdSDarrick J. Wong sector_t block_nr, 150cc8e94fdSDarrick J. Wong struct ext4_xattr_header *hdr) 151cc8e94fdSDarrick J. Wong { 1529aa5d32bSDmitry Monakhov if (!ext4_has_metadata_csum(inode->i_sb)) 153cc8e94fdSDarrick J. Wong return; 154cc8e94fdSDarrick J. Wong 155cc8e94fdSDarrick J. Wong hdr->h_checksum = ext4_xattr_block_csum(inode, block_nr, hdr); 156cc8e94fdSDarrick J. Wong } 157cc8e94fdSDarrick J. Wong 158cc8e94fdSDarrick J. Wong static inline int ext4_handle_dirty_xattr_block(handle_t *handle, 159cc8e94fdSDarrick J. Wong struct inode *inode, 160cc8e94fdSDarrick J. Wong struct buffer_head *bh) 161cc8e94fdSDarrick J. Wong { 162cc8e94fdSDarrick J. Wong ext4_xattr_block_csum_set(inode, bh->b_blocknr, BHDR(bh)); 163cc8e94fdSDarrick J. Wong return ext4_handle_dirty_metadata(handle, inode, bh); 164cc8e94fdSDarrick J. Wong } 165cc8e94fdSDarrick J. Wong 16611e27528SStephen Hemminger static inline const struct xattr_handler * 167617ba13bSMingming Cao ext4_xattr_handler(int name_index) 168ac27a0ecSDave Kleikamp { 16911e27528SStephen Hemminger const struct xattr_handler *handler = NULL; 170ac27a0ecSDave Kleikamp 171617ba13bSMingming Cao if (name_index > 0 && name_index < ARRAY_SIZE(ext4_xattr_handler_map)) 172617ba13bSMingming Cao handler = ext4_xattr_handler_map[name_index]; 173ac27a0ecSDave Kleikamp return handler; 174ac27a0ecSDave Kleikamp } 175ac27a0ecSDave Kleikamp 176ac27a0ecSDave Kleikamp /* 177ac27a0ecSDave Kleikamp * Inode operation listxattr() 178ac27a0ecSDave Kleikamp * 1792b0143b5SDavid Howells * d_inode(dentry)->i_mutex: don't care 180ac27a0ecSDave Kleikamp */ 181ac27a0ecSDave Kleikamp ssize_t 182617ba13bSMingming Cao ext4_listxattr(struct dentry *dentry, char *buffer, size_t size) 183ac27a0ecSDave Kleikamp { 184431547b3SChristoph Hellwig return ext4_xattr_list(dentry, buffer, size); 185ac27a0ecSDave Kleikamp } 186ac27a0ecSDave Kleikamp 187ac27a0ecSDave Kleikamp static int 188a0626e75SDarrick J. Wong ext4_xattr_check_names(struct ext4_xattr_entry *entry, void *end, 189a0626e75SDarrick J. Wong void *value_start) 190ac27a0ecSDave Kleikamp { 191a0626e75SDarrick J. Wong struct ext4_xattr_entry *e = entry; 192a0626e75SDarrick J. Wong 193a0626e75SDarrick J. Wong while (!IS_LAST_ENTRY(e)) { 194a0626e75SDarrick J. Wong struct ext4_xattr_entry *next = EXT4_XATTR_NEXT(e); 195ac27a0ecSDave Kleikamp if ((void *)next >= end) 1966a797d27SDarrick J. Wong return -EFSCORRUPTED; 197a0626e75SDarrick J. Wong e = next; 198ac27a0ecSDave Kleikamp } 199a0626e75SDarrick J. Wong 200a0626e75SDarrick J. Wong while (!IS_LAST_ENTRY(entry)) { 201a0626e75SDarrick J. Wong if (entry->e_value_size != 0 && 202a0626e75SDarrick J. Wong (value_start + le16_to_cpu(entry->e_value_offs) < 203a0626e75SDarrick J. Wong (void *)e + sizeof(__u32) || 204a0626e75SDarrick J. Wong value_start + le16_to_cpu(entry->e_value_offs) + 205a0626e75SDarrick J. Wong le32_to_cpu(entry->e_value_size) > end)) 2066a797d27SDarrick J. Wong return -EFSCORRUPTED; 207a0626e75SDarrick J. Wong entry = EXT4_XATTR_NEXT(entry); 208a0626e75SDarrick J. Wong } 209a0626e75SDarrick J. Wong 210ac27a0ecSDave Kleikamp return 0; 211ac27a0ecSDave Kleikamp } 212ac27a0ecSDave Kleikamp 213ac27a0ecSDave Kleikamp static inline int 214cc8e94fdSDarrick J. Wong ext4_xattr_check_block(struct inode *inode, struct buffer_head *bh) 215ac27a0ecSDave Kleikamp { 216cc8e94fdSDarrick J. Wong int error; 217cc8e94fdSDarrick J. Wong 218cc8e94fdSDarrick J. Wong if (buffer_verified(bh)) 219cc8e94fdSDarrick J. Wong return 0; 220cc8e94fdSDarrick J. Wong 221617ba13bSMingming Cao if (BHDR(bh)->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC) || 222ac27a0ecSDave Kleikamp BHDR(bh)->h_blocks != cpu_to_le32(1)) 2236a797d27SDarrick J. Wong return -EFSCORRUPTED; 224cc8e94fdSDarrick J. Wong if (!ext4_xattr_block_csum_verify(inode, bh->b_blocknr, BHDR(bh))) 2256a797d27SDarrick J. Wong return -EFSBADCRC; 226a0626e75SDarrick J. Wong error = ext4_xattr_check_names(BFIRST(bh), bh->b_data + bh->b_size, 227a0626e75SDarrick J. Wong bh->b_data); 228cc8e94fdSDarrick J. Wong if (!error) 229cc8e94fdSDarrick J. Wong set_buffer_verified(bh); 230cc8e94fdSDarrick J. Wong return error; 231ac27a0ecSDave Kleikamp } 232ac27a0ecSDave Kleikamp 233*9e92f48cSTheodore Ts'o static int 234*9e92f48cSTheodore Ts'o __xattr_check_inode(struct inode *inode, struct ext4_xattr_ibody_header *header, 235*9e92f48cSTheodore Ts'o void *end, const char *function, unsigned int line) 236*9e92f48cSTheodore Ts'o { 237*9e92f48cSTheodore Ts'o struct ext4_xattr_entry *entry = IFIRST(header); 238*9e92f48cSTheodore Ts'o int error = -EFSCORRUPTED; 239*9e92f48cSTheodore Ts'o 240*9e92f48cSTheodore Ts'o if (((void *) header >= end) || 241*9e92f48cSTheodore Ts'o (header->h_magic != le32_to_cpu(EXT4_XATTR_MAGIC))) 242*9e92f48cSTheodore Ts'o goto errout; 243*9e92f48cSTheodore Ts'o error = ext4_xattr_check_names(entry, end, entry); 244*9e92f48cSTheodore Ts'o errout: 245*9e92f48cSTheodore Ts'o if (error) 246*9e92f48cSTheodore Ts'o __ext4_error_inode(inode, function, line, 0, 247*9e92f48cSTheodore Ts'o "corrupted in-inode xattr"); 248*9e92f48cSTheodore Ts'o return error; 249*9e92f48cSTheodore Ts'o } 250*9e92f48cSTheodore Ts'o 251*9e92f48cSTheodore Ts'o #define xattr_check_inode(inode, header, end) \ 252*9e92f48cSTheodore Ts'o __xattr_check_inode((inode), (header), (end), __func__, __LINE__) 253*9e92f48cSTheodore Ts'o 254ac27a0ecSDave Kleikamp static inline int 255617ba13bSMingming Cao ext4_xattr_check_entry(struct ext4_xattr_entry *entry, size_t size) 256ac27a0ecSDave Kleikamp { 257ac27a0ecSDave Kleikamp size_t value_size = le32_to_cpu(entry->e_value_size); 258ac27a0ecSDave Kleikamp 259ac27a0ecSDave Kleikamp if (entry->e_value_block != 0 || value_size > size || 260ac27a0ecSDave Kleikamp le16_to_cpu(entry->e_value_offs) + value_size > size) 2616a797d27SDarrick J. Wong return -EFSCORRUPTED; 262ac27a0ecSDave Kleikamp return 0; 263ac27a0ecSDave Kleikamp } 264ac27a0ecSDave Kleikamp 265ac27a0ecSDave Kleikamp static int 266617ba13bSMingming Cao ext4_xattr_find_entry(struct ext4_xattr_entry **pentry, int name_index, 267ac27a0ecSDave Kleikamp const char *name, size_t size, int sorted) 268ac27a0ecSDave Kleikamp { 269617ba13bSMingming Cao struct ext4_xattr_entry *entry; 270ac27a0ecSDave Kleikamp size_t name_len; 271ac27a0ecSDave Kleikamp int cmp = 1; 272ac27a0ecSDave Kleikamp 273ac27a0ecSDave Kleikamp if (name == NULL) 274ac27a0ecSDave Kleikamp return -EINVAL; 275ac27a0ecSDave Kleikamp name_len = strlen(name); 276ac27a0ecSDave Kleikamp entry = *pentry; 277617ba13bSMingming Cao for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) { 278ac27a0ecSDave Kleikamp cmp = name_index - entry->e_name_index; 279ac27a0ecSDave Kleikamp if (!cmp) 280ac27a0ecSDave Kleikamp cmp = name_len - entry->e_name_len; 281ac27a0ecSDave Kleikamp if (!cmp) 282ac27a0ecSDave Kleikamp cmp = memcmp(name, entry->e_name, name_len); 283ac27a0ecSDave Kleikamp if (cmp <= 0 && (sorted || cmp == 0)) 284ac27a0ecSDave Kleikamp break; 285ac27a0ecSDave Kleikamp } 286ac27a0ecSDave Kleikamp *pentry = entry; 287617ba13bSMingming Cao if (!cmp && ext4_xattr_check_entry(entry, size)) 2886a797d27SDarrick J. Wong return -EFSCORRUPTED; 289ac27a0ecSDave Kleikamp return cmp ? -ENODATA : 0; 290ac27a0ecSDave Kleikamp } 291ac27a0ecSDave Kleikamp 292ac27a0ecSDave Kleikamp static int 293617ba13bSMingming Cao ext4_xattr_block_get(struct inode *inode, int name_index, const char *name, 294ac27a0ecSDave Kleikamp void *buffer, size_t buffer_size) 295ac27a0ecSDave Kleikamp { 296ac27a0ecSDave Kleikamp struct buffer_head *bh = NULL; 297617ba13bSMingming Cao struct ext4_xattr_entry *entry; 298ac27a0ecSDave Kleikamp size_t size; 299ac27a0ecSDave Kleikamp int error; 3007a2508e1SJan Kara struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); 301ac27a0ecSDave Kleikamp 302ac27a0ecSDave Kleikamp ea_idebug(inode, "name=%d.%s, buffer=%p, buffer_size=%ld", 303ac27a0ecSDave Kleikamp name_index, name, buffer, (long)buffer_size); 304ac27a0ecSDave Kleikamp 305ac27a0ecSDave Kleikamp error = -ENODATA; 306617ba13bSMingming Cao if (!EXT4_I(inode)->i_file_acl) 307ac27a0ecSDave Kleikamp goto cleanup; 308ace36ad4SJoe Perches ea_idebug(inode, "reading block %llu", 309ace36ad4SJoe Perches (unsigned long long)EXT4_I(inode)->i_file_acl); 310617ba13bSMingming Cao bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); 311ac27a0ecSDave Kleikamp if (!bh) 312ac27a0ecSDave Kleikamp goto cleanup; 313ac27a0ecSDave Kleikamp ea_bdebug(bh, "b_count=%d, refcount=%d", 314ac27a0ecSDave Kleikamp atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount)); 315cc8e94fdSDarrick J. Wong if (ext4_xattr_check_block(inode, bh)) { 31612062dddSEric Sandeen bad_block: 31724676da4STheodore Ts'o EXT4_ERROR_INODE(inode, "bad block %llu", 318617ba13bSMingming Cao EXT4_I(inode)->i_file_acl); 3196a797d27SDarrick J. Wong error = -EFSCORRUPTED; 320ac27a0ecSDave Kleikamp goto cleanup; 321ac27a0ecSDave Kleikamp } 3229c191f70ST Makphaibulchoke ext4_xattr_cache_insert(ext4_mb_cache, bh); 323ac27a0ecSDave Kleikamp entry = BFIRST(bh); 324617ba13bSMingming Cao error = ext4_xattr_find_entry(&entry, name_index, name, bh->b_size, 1); 3256a797d27SDarrick J. Wong if (error == -EFSCORRUPTED) 326ac27a0ecSDave Kleikamp goto bad_block; 327ac27a0ecSDave Kleikamp if (error) 328ac27a0ecSDave Kleikamp goto cleanup; 329ac27a0ecSDave Kleikamp size = le32_to_cpu(entry->e_value_size); 330ac27a0ecSDave Kleikamp if (buffer) { 331ac27a0ecSDave Kleikamp error = -ERANGE; 332ac27a0ecSDave Kleikamp if (size > buffer_size) 333ac27a0ecSDave Kleikamp goto cleanup; 334ac27a0ecSDave Kleikamp memcpy(buffer, bh->b_data + le16_to_cpu(entry->e_value_offs), 335ac27a0ecSDave Kleikamp size); 336ac27a0ecSDave Kleikamp } 337ac27a0ecSDave Kleikamp error = size; 338ac27a0ecSDave Kleikamp 339ac27a0ecSDave Kleikamp cleanup: 340ac27a0ecSDave Kleikamp brelse(bh); 341ac27a0ecSDave Kleikamp return error; 342ac27a0ecSDave Kleikamp } 343ac27a0ecSDave Kleikamp 344879b3825STao Ma int 345617ba13bSMingming Cao ext4_xattr_ibody_get(struct inode *inode, int name_index, const char *name, 346ac27a0ecSDave Kleikamp void *buffer, size_t buffer_size) 347ac27a0ecSDave Kleikamp { 348617ba13bSMingming Cao struct ext4_xattr_ibody_header *header; 349617ba13bSMingming Cao struct ext4_xattr_entry *entry; 350617ba13bSMingming Cao struct ext4_inode *raw_inode; 351617ba13bSMingming Cao struct ext4_iloc iloc; 352ac27a0ecSDave Kleikamp size_t size; 353ac27a0ecSDave Kleikamp void *end; 354ac27a0ecSDave Kleikamp int error; 355ac27a0ecSDave Kleikamp 35619f5fb7aSTheodore Ts'o if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR)) 357ac27a0ecSDave Kleikamp return -ENODATA; 358617ba13bSMingming Cao error = ext4_get_inode_loc(inode, &iloc); 359ac27a0ecSDave Kleikamp if (error) 360ac27a0ecSDave Kleikamp return error; 361617ba13bSMingming Cao raw_inode = ext4_raw_inode(&iloc); 362ac27a0ecSDave Kleikamp header = IHDR(inode, raw_inode); 363ac27a0ecSDave Kleikamp entry = IFIRST(header); 364617ba13bSMingming Cao end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; 365*9e92f48cSTheodore Ts'o error = xattr_check_inode(inode, header, end); 366ac27a0ecSDave Kleikamp if (error) 367ac27a0ecSDave Kleikamp goto cleanup; 368617ba13bSMingming Cao error = ext4_xattr_find_entry(&entry, name_index, name, 369ac27a0ecSDave Kleikamp end - (void *)entry, 0); 370ac27a0ecSDave Kleikamp if (error) 371ac27a0ecSDave Kleikamp goto cleanup; 372ac27a0ecSDave Kleikamp size = le32_to_cpu(entry->e_value_size); 373ac27a0ecSDave Kleikamp if (buffer) { 374ac27a0ecSDave Kleikamp error = -ERANGE; 375ac27a0ecSDave Kleikamp if (size > buffer_size) 376ac27a0ecSDave Kleikamp goto cleanup; 377ac27a0ecSDave Kleikamp memcpy(buffer, (void *)IFIRST(header) + 378ac27a0ecSDave Kleikamp le16_to_cpu(entry->e_value_offs), size); 379ac27a0ecSDave Kleikamp } 380ac27a0ecSDave Kleikamp error = size; 381ac27a0ecSDave Kleikamp 382ac27a0ecSDave Kleikamp cleanup: 383ac27a0ecSDave Kleikamp brelse(iloc.bh); 384ac27a0ecSDave Kleikamp return error; 385ac27a0ecSDave Kleikamp } 386ac27a0ecSDave Kleikamp 387ac27a0ecSDave Kleikamp /* 388617ba13bSMingming Cao * ext4_xattr_get() 389ac27a0ecSDave Kleikamp * 390ac27a0ecSDave Kleikamp * Copy an extended attribute into the buffer 391ac27a0ecSDave Kleikamp * provided, or compute the buffer size required. 392ac27a0ecSDave Kleikamp * Buffer is NULL to compute the size of the buffer required. 393ac27a0ecSDave Kleikamp * 394ac27a0ecSDave Kleikamp * Returns a negative error number on failure, or the number of bytes 395ac27a0ecSDave Kleikamp * used / required on success. 396ac27a0ecSDave Kleikamp */ 397ac27a0ecSDave Kleikamp int 398617ba13bSMingming Cao ext4_xattr_get(struct inode *inode, int name_index, const char *name, 399ac27a0ecSDave Kleikamp void *buffer, size_t buffer_size) 400ac27a0ecSDave Kleikamp { 401ac27a0ecSDave Kleikamp int error; 402ac27a0ecSDave Kleikamp 403230b8c1aSZhang Zhen if (strlen(name) > 255) 404230b8c1aSZhang Zhen return -ERANGE; 405230b8c1aSZhang Zhen 406617ba13bSMingming Cao down_read(&EXT4_I(inode)->xattr_sem); 407617ba13bSMingming Cao error = ext4_xattr_ibody_get(inode, name_index, name, buffer, 408ac27a0ecSDave Kleikamp buffer_size); 409ac27a0ecSDave Kleikamp if (error == -ENODATA) 410617ba13bSMingming Cao error = ext4_xattr_block_get(inode, name_index, name, buffer, 411ac27a0ecSDave Kleikamp buffer_size); 412617ba13bSMingming Cao up_read(&EXT4_I(inode)->xattr_sem); 413ac27a0ecSDave Kleikamp return error; 414ac27a0ecSDave Kleikamp } 415ac27a0ecSDave Kleikamp 416ac27a0ecSDave Kleikamp static int 417431547b3SChristoph Hellwig ext4_xattr_list_entries(struct dentry *dentry, struct ext4_xattr_entry *entry, 418ac27a0ecSDave Kleikamp char *buffer, size_t buffer_size) 419ac27a0ecSDave Kleikamp { 420ac27a0ecSDave Kleikamp size_t rest = buffer_size; 421ac27a0ecSDave Kleikamp 422617ba13bSMingming Cao for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) { 42311e27528SStephen Hemminger const struct xattr_handler *handler = 424617ba13bSMingming Cao ext4_xattr_handler(entry->e_name_index); 425ac27a0ecSDave Kleikamp 426764a5c6bSAndreas Gruenbacher if (handler && (!handler->list || handler->list(dentry))) { 427764a5c6bSAndreas Gruenbacher const char *prefix = handler->prefix ?: handler->name; 428764a5c6bSAndreas Gruenbacher size_t prefix_len = strlen(prefix); 429764a5c6bSAndreas Gruenbacher size_t size = prefix_len + entry->e_name_len + 1; 430764a5c6bSAndreas Gruenbacher 431ac27a0ecSDave Kleikamp if (buffer) { 432ac27a0ecSDave Kleikamp if (size > rest) 433ac27a0ecSDave Kleikamp return -ERANGE; 434764a5c6bSAndreas Gruenbacher memcpy(buffer, prefix, prefix_len); 435764a5c6bSAndreas Gruenbacher buffer += prefix_len; 436764a5c6bSAndreas Gruenbacher memcpy(buffer, entry->e_name, entry->e_name_len); 437764a5c6bSAndreas Gruenbacher buffer += entry->e_name_len; 438764a5c6bSAndreas Gruenbacher *buffer++ = 0; 439ac27a0ecSDave Kleikamp } 440ac27a0ecSDave Kleikamp rest -= size; 441ac27a0ecSDave Kleikamp } 442ac27a0ecSDave Kleikamp } 443764a5c6bSAndreas Gruenbacher return buffer_size - rest; /* total size */ 444ac27a0ecSDave Kleikamp } 445ac27a0ecSDave Kleikamp 446ac27a0ecSDave Kleikamp static int 447431547b3SChristoph Hellwig ext4_xattr_block_list(struct dentry *dentry, char *buffer, size_t buffer_size) 448ac27a0ecSDave Kleikamp { 4492b0143b5SDavid Howells struct inode *inode = d_inode(dentry); 450ac27a0ecSDave Kleikamp struct buffer_head *bh = NULL; 451ac27a0ecSDave Kleikamp int error; 4527a2508e1SJan Kara struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); 453ac27a0ecSDave Kleikamp 454ac27a0ecSDave Kleikamp ea_idebug(inode, "buffer=%p, buffer_size=%ld", 455ac27a0ecSDave Kleikamp buffer, (long)buffer_size); 456ac27a0ecSDave Kleikamp 457ac27a0ecSDave Kleikamp error = 0; 458617ba13bSMingming Cao if (!EXT4_I(inode)->i_file_acl) 459ac27a0ecSDave Kleikamp goto cleanup; 460ace36ad4SJoe Perches ea_idebug(inode, "reading block %llu", 461ace36ad4SJoe Perches (unsigned long long)EXT4_I(inode)->i_file_acl); 462617ba13bSMingming Cao bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); 463ac27a0ecSDave Kleikamp error = -EIO; 464ac27a0ecSDave Kleikamp if (!bh) 465ac27a0ecSDave Kleikamp goto cleanup; 466ac27a0ecSDave Kleikamp ea_bdebug(bh, "b_count=%d, refcount=%d", 467ac27a0ecSDave Kleikamp atomic_read(&(bh->b_count)), le32_to_cpu(BHDR(bh)->h_refcount)); 468cc8e94fdSDarrick J. Wong if (ext4_xattr_check_block(inode, bh)) { 46924676da4STheodore Ts'o EXT4_ERROR_INODE(inode, "bad block %llu", 470617ba13bSMingming Cao EXT4_I(inode)->i_file_acl); 4716a797d27SDarrick J. Wong error = -EFSCORRUPTED; 472ac27a0ecSDave Kleikamp goto cleanup; 473ac27a0ecSDave Kleikamp } 4749c191f70ST Makphaibulchoke ext4_xattr_cache_insert(ext4_mb_cache, bh); 475431547b3SChristoph Hellwig error = ext4_xattr_list_entries(dentry, BFIRST(bh), buffer, buffer_size); 476ac27a0ecSDave Kleikamp 477ac27a0ecSDave Kleikamp cleanup: 478ac27a0ecSDave Kleikamp brelse(bh); 479ac27a0ecSDave Kleikamp 480ac27a0ecSDave Kleikamp return error; 481ac27a0ecSDave Kleikamp } 482ac27a0ecSDave Kleikamp 483ac27a0ecSDave Kleikamp static int 484431547b3SChristoph Hellwig ext4_xattr_ibody_list(struct dentry *dentry, char *buffer, size_t buffer_size) 485ac27a0ecSDave Kleikamp { 4862b0143b5SDavid Howells struct inode *inode = d_inode(dentry); 487617ba13bSMingming Cao struct ext4_xattr_ibody_header *header; 488617ba13bSMingming Cao struct ext4_inode *raw_inode; 489617ba13bSMingming Cao struct ext4_iloc iloc; 490ac27a0ecSDave Kleikamp void *end; 491ac27a0ecSDave Kleikamp int error; 492ac27a0ecSDave Kleikamp 49319f5fb7aSTheodore Ts'o if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR)) 494ac27a0ecSDave Kleikamp return 0; 495617ba13bSMingming Cao error = ext4_get_inode_loc(inode, &iloc); 496ac27a0ecSDave Kleikamp if (error) 497ac27a0ecSDave Kleikamp return error; 498617ba13bSMingming Cao raw_inode = ext4_raw_inode(&iloc); 499ac27a0ecSDave Kleikamp header = IHDR(inode, raw_inode); 500617ba13bSMingming Cao end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; 501*9e92f48cSTheodore Ts'o error = xattr_check_inode(inode, header, end); 502ac27a0ecSDave Kleikamp if (error) 503ac27a0ecSDave Kleikamp goto cleanup; 504431547b3SChristoph Hellwig error = ext4_xattr_list_entries(dentry, IFIRST(header), 505ac27a0ecSDave Kleikamp buffer, buffer_size); 506ac27a0ecSDave Kleikamp 507ac27a0ecSDave Kleikamp cleanup: 508ac27a0ecSDave Kleikamp brelse(iloc.bh); 509ac27a0ecSDave Kleikamp return error; 510ac27a0ecSDave Kleikamp } 511ac27a0ecSDave Kleikamp 512ac27a0ecSDave Kleikamp /* 513617ba13bSMingming Cao * ext4_xattr_list() 514ac27a0ecSDave Kleikamp * 515ac27a0ecSDave Kleikamp * Copy a list of attribute names into the buffer 516ac27a0ecSDave Kleikamp * provided, or compute the buffer size required. 517ac27a0ecSDave Kleikamp * Buffer is NULL to compute the size of the buffer required. 518ac27a0ecSDave Kleikamp * 519ac27a0ecSDave Kleikamp * Returns a negative error number on failure, or the number of bytes 520ac27a0ecSDave Kleikamp * used / required on success. 521ac27a0ecSDave Kleikamp */ 522d3a95d47SMingming Cao static int 523431547b3SChristoph Hellwig ext4_xattr_list(struct dentry *dentry, char *buffer, size_t buffer_size) 524ac27a0ecSDave Kleikamp { 525eaeef867STheodore Ts'o int ret, ret2; 526ac27a0ecSDave Kleikamp 5272b0143b5SDavid Howells down_read(&EXT4_I(d_inode(dentry))->xattr_sem); 528eaeef867STheodore Ts'o ret = ret2 = ext4_xattr_ibody_list(dentry, buffer, buffer_size); 529eaeef867STheodore Ts'o if (ret < 0) 530eaeef867STheodore Ts'o goto errout; 531ac27a0ecSDave Kleikamp if (buffer) { 532eaeef867STheodore Ts'o buffer += ret; 533eaeef867STheodore Ts'o buffer_size -= ret; 534ac27a0ecSDave Kleikamp } 535eaeef867STheodore Ts'o ret = ext4_xattr_block_list(dentry, buffer, buffer_size); 536eaeef867STheodore Ts'o if (ret < 0) 537eaeef867STheodore Ts'o goto errout; 538eaeef867STheodore Ts'o ret += ret2; 539eaeef867STheodore Ts'o errout: 5402b0143b5SDavid Howells up_read(&EXT4_I(d_inode(dentry))->xattr_sem); 541eaeef867STheodore Ts'o return ret; 542ac27a0ecSDave Kleikamp } 543ac27a0ecSDave Kleikamp 544ac27a0ecSDave Kleikamp /* 545617ba13bSMingming Cao * If the EXT4_FEATURE_COMPAT_EXT_ATTR feature of this file system is 546ac27a0ecSDave Kleikamp * not set, set it. 547ac27a0ecSDave Kleikamp */ 548617ba13bSMingming Cao static void ext4_xattr_update_super_block(handle_t *handle, 549ac27a0ecSDave Kleikamp struct super_block *sb) 550ac27a0ecSDave Kleikamp { 551e2b911c5SDarrick J. Wong if (ext4_has_feature_xattr(sb)) 552ac27a0ecSDave Kleikamp return; 553ac27a0ecSDave Kleikamp 5545d601255Sliang xie BUFFER_TRACE(EXT4_SB(sb)->s_sbh, "get_write_access"); 555617ba13bSMingming Cao if (ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh) == 0) { 556e2b911c5SDarrick J. Wong ext4_set_feature_xattr(sb); 557a0375156STheodore Ts'o ext4_handle_dirty_super(handle, sb); 558ac27a0ecSDave Kleikamp } 559ac27a0ecSDave Kleikamp } 560ac27a0ecSDave Kleikamp 561ac27a0ecSDave Kleikamp /* 562ec4cb1aaSJan Kara * Release the xattr block BH: If the reference count is > 1, decrement it; 563ec4cb1aaSJan Kara * otherwise free the block. 564ac27a0ecSDave Kleikamp */ 565ac27a0ecSDave Kleikamp static void 566617ba13bSMingming Cao ext4_xattr_release_block(handle_t *handle, struct inode *inode, 567ac27a0ecSDave Kleikamp struct buffer_head *bh) 568ac27a0ecSDave Kleikamp { 5696048c64bSAndreas Gruenbacher struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); 5706048c64bSAndreas Gruenbacher u32 hash, ref; 5718a2bfdcbSMingming Cao int error = 0; 572ac27a0ecSDave Kleikamp 5735d601255Sliang xie BUFFER_TRACE(bh, "get_write_access"); 5748a2bfdcbSMingming Cao error = ext4_journal_get_write_access(handle, bh); 5758a2bfdcbSMingming Cao if (error) 5768a2bfdcbSMingming Cao goto out; 5778a2bfdcbSMingming Cao 5788a2bfdcbSMingming Cao lock_buffer(bh); 5796048c64bSAndreas Gruenbacher hash = le32_to_cpu(BHDR(bh)->h_hash); 5806048c64bSAndreas Gruenbacher ref = le32_to_cpu(BHDR(bh)->h_refcount); 5816048c64bSAndreas Gruenbacher if (ref == 1) { 582ac27a0ecSDave Kleikamp ea_bdebug(bh, "refcount now=0; freeing"); 58382939d79SJan Kara /* 58482939d79SJan Kara * This must happen under buffer lock for 58582939d79SJan Kara * ext4_xattr_block_set() to reliably detect freed block 58682939d79SJan Kara */ 5876048c64bSAndreas Gruenbacher mb_cache_entry_delete_block(ext4_mb_cache, hash, bh->b_blocknr); 588ac27a0ecSDave Kleikamp get_bh(bh); 589ec4cb1aaSJan Kara unlock_buffer(bh); 590e6362609STheodore Ts'o ext4_free_blocks(handle, inode, bh, 0, 1, 591e6362609STheodore Ts'o EXT4_FREE_BLOCKS_METADATA | 592e6362609STheodore Ts'o EXT4_FREE_BLOCKS_FORGET); 593ac27a0ecSDave Kleikamp } else { 5946048c64bSAndreas Gruenbacher ref--; 5956048c64bSAndreas Gruenbacher BHDR(bh)->h_refcount = cpu_to_le32(ref); 5966048c64bSAndreas Gruenbacher if (ref == EXT4_XATTR_REFCOUNT_MAX - 1) { 5976048c64bSAndreas Gruenbacher struct mb_cache_entry *ce; 5986048c64bSAndreas Gruenbacher 5996048c64bSAndreas Gruenbacher ce = mb_cache_entry_get(ext4_mb_cache, hash, 6006048c64bSAndreas Gruenbacher bh->b_blocknr); 6016048c64bSAndreas Gruenbacher if (ce) { 6026048c64bSAndreas Gruenbacher ce->e_reusable = 1; 6036048c64bSAndreas Gruenbacher mb_cache_entry_put(ext4_mb_cache, ce); 6046048c64bSAndreas Gruenbacher } 6056048c64bSAndreas Gruenbacher } 6066048c64bSAndreas Gruenbacher 607ec4cb1aaSJan Kara /* 608ec4cb1aaSJan Kara * Beware of this ugliness: Releasing of xattr block references 609ec4cb1aaSJan Kara * from different inodes can race and so we have to protect 610ec4cb1aaSJan Kara * from a race where someone else frees the block (and releases 611ec4cb1aaSJan Kara * its journal_head) before we are done dirtying the buffer. In 612ec4cb1aaSJan Kara * nojournal mode this race is harmless and we actually cannot 613ec4cb1aaSJan Kara * call ext4_handle_dirty_xattr_block() with locked buffer as 614ec4cb1aaSJan Kara * that function can call sync_dirty_buffer() so for that case 615ec4cb1aaSJan Kara * we handle the dirtying after unlocking the buffer. 616ec4cb1aaSJan Kara */ 617ec4cb1aaSJan Kara if (ext4_handle_valid(handle)) 618ec4cb1aaSJan Kara error = ext4_handle_dirty_xattr_block(handle, inode, 619ec4cb1aaSJan Kara bh); 620c1bb05a6SEric Sandeen unlock_buffer(bh); 621ec4cb1aaSJan Kara if (!ext4_handle_valid(handle)) 622ec4cb1aaSJan Kara error = ext4_handle_dirty_xattr_block(handle, inode, 623ec4cb1aaSJan Kara bh); 624ac27a0ecSDave Kleikamp if (IS_SYNC(inode)) 6250390131bSFrank Mayhar ext4_handle_sync(handle); 6261231b3a1SLukas Czerner dquot_free_block(inode, EXT4_C2B(EXT4_SB(inode->i_sb), 1)); 627ac27a0ecSDave Kleikamp ea_bdebug(bh, "refcount now=%d; releasing", 628ac27a0ecSDave Kleikamp le32_to_cpu(BHDR(bh)->h_refcount)); 629ac27a0ecSDave Kleikamp } 6308a2bfdcbSMingming Cao out: 6318a2bfdcbSMingming Cao ext4_std_error(inode->i_sb, error); 6328a2bfdcbSMingming Cao return; 633ac27a0ecSDave Kleikamp } 634ac27a0ecSDave Kleikamp 6356dd4ee7cSKalpak Shah /* 6366dd4ee7cSKalpak Shah * Find the available free space for EAs. This also returns the total number of 6376dd4ee7cSKalpak Shah * bytes used by EA entries. 6386dd4ee7cSKalpak Shah */ 6396dd4ee7cSKalpak Shah static size_t ext4_xattr_free_space(struct ext4_xattr_entry *last, 6406dd4ee7cSKalpak Shah size_t *min_offs, void *base, int *total) 6416dd4ee7cSKalpak Shah { 6426dd4ee7cSKalpak Shah for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { 6436dd4ee7cSKalpak Shah if (!last->e_value_block && last->e_value_size) { 6446dd4ee7cSKalpak Shah size_t offs = le16_to_cpu(last->e_value_offs); 6456dd4ee7cSKalpak Shah if (offs < *min_offs) 6466dd4ee7cSKalpak Shah *min_offs = offs; 6476dd4ee7cSKalpak Shah } 6487b1b2c1bSTheodore Ts'o if (total) 6497b1b2c1bSTheodore Ts'o *total += EXT4_XATTR_LEN(last->e_name_len); 6506dd4ee7cSKalpak Shah } 6516dd4ee7cSKalpak Shah return (*min_offs - ((void *)last - base) - sizeof(__u32)); 6526dd4ee7cSKalpak Shah } 6536dd4ee7cSKalpak Shah 654ac27a0ecSDave Kleikamp static int 655617ba13bSMingming Cao ext4_xattr_set_entry(struct ext4_xattr_info *i, struct ext4_xattr_search *s) 656ac27a0ecSDave Kleikamp { 657617ba13bSMingming Cao struct ext4_xattr_entry *last; 658ac27a0ecSDave Kleikamp size_t free, min_offs = s->end - s->base, name_len = strlen(i->name); 659ac27a0ecSDave Kleikamp 660ac27a0ecSDave Kleikamp /* Compute min_offs and last. */ 661ac27a0ecSDave Kleikamp last = s->first; 662617ba13bSMingming Cao for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { 663ac27a0ecSDave Kleikamp if (!last->e_value_block && last->e_value_size) { 664ac27a0ecSDave Kleikamp size_t offs = le16_to_cpu(last->e_value_offs); 665ac27a0ecSDave Kleikamp if (offs < min_offs) 666ac27a0ecSDave Kleikamp min_offs = offs; 667ac27a0ecSDave Kleikamp } 668ac27a0ecSDave Kleikamp } 669ac27a0ecSDave Kleikamp free = min_offs - ((void *)last - s->base) - sizeof(__u32); 670ac27a0ecSDave Kleikamp if (!s->not_found) { 671ac27a0ecSDave Kleikamp if (!s->here->e_value_block && s->here->e_value_size) { 672ac27a0ecSDave Kleikamp size_t size = le32_to_cpu(s->here->e_value_size); 673617ba13bSMingming Cao free += EXT4_XATTR_SIZE(size); 674ac27a0ecSDave Kleikamp } 675617ba13bSMingming Cao free += EXT4_XATTR_LEN(name_len); 676ac27a0ecSDave Kleikamp } 677ac27a0ecSDave Kleikamp if (i->value) { 6785f80f62aSWei Yuan if (free < EXT4_XATTR_LEN(name_len) + 679617ba13bSMingming Cao EXT4_XATTR_SIZE(i->value_len)) 680ac27a0ecSDave Kleikamp return -ENOSPC; 681ac27a0ecSDave Kleikamp } 682ac27a0ecSDave Kleikamp 683ac27a0ecSDave Kleikamp if (i->value && s->not_found) { 684ac27a0ecSDave Kleikamp /* Insert the new name. */ 685617ba13bSMingming Cao size_t size = EXT4_XATTR_LEN(name_len); 686ac27a0ecSDave Kleikamp size_t rest = (void *)last - (void *)s->here + sizeof(__u32); 687ac27a0ecSDave Kleikamp memmove((void *)s->here + size, s->here, rest); 688ac27a0ecSDave Kleikamp memset(s->here, 0, size); 689ac27a0ecSDave Kleikamp s->here->e_name_index = i->name_index; 690ac27a0ecSDave Kleikamp s->here->e_name_len = name_len; 691ac27a0ecSDave Kleikamp memcpy(s->here->e_name, i->name, name_len); 692ac27a0ecSDave Kleikamp } else { 693ac27a0ecSDave Kleikamp if (!s->here->e_value_block && s->here->e_value_size) { 694ac27a0ecSDave Kleikamp void *first_val = s->base + min_offs; 695ac27a0ecSDave Kleikamp size_t offs = le16_to_cpu(s->here->e_value_offs); 696ac27a0ecSDave Kleikamp void *val = s->base + offs; 697617ba13bSMingming Cao size_t size = EXT4_XATTR_SIZE( 698ac27a0ecSDave Kleikamp le32_to_cpu(s->here->e_value_size)); 699ac27a0ecSDave Kleikamp 700617ba13bSMingming Cao if (i->value && size == EXT4_XATTR_SIZE(i->value_len)) { 701ac27a0ecSDave Kleikamp /* The old and the new value have the same 702ac27a0ecSDave Kleikamp size. Just replace. */ 703ac27a0ecSDave Kleikamp s->here->e_value_size = 704ac27a0ecSDave Kleikamp cpu_to_le32(i->value_len); 705bd9926e8STheodore Ts'o if (i->value == EXT4_ZERO_XATTR_VALUE) { 706bd9926e8STheodore Ts'o memset(val, 0, size); 707bd9926e8STheodore Ts'o } else { 708bd9926e8STheodore Ts'o /* Clear pad bytes first. */ 709617ba13bSMingming Cao memset(val + size - EXT4_XATTR_PAD, 0, 710bd9926e8STheodore Ts'o EXT4_XATTR_PAD); 711ac27a0ecSDave Kleikamp memcpy(val, i->value, i->value_len); 712bd9926e8STheodore Ts'o } 713ac27a0ecSDave Kleikamp return 0; 714ac27a0ecSDave Kleikamp } 715ac27a0ecSDave Kleikamp 716ac27a0ecSDave Kleikamp /* Remove the old value. */ 717ac27a0ecSDave Kleikamp memmove(first_val + size, first_val, val - first_val); 718ac27a0ecSDave Kleikamp memset(first_val, 0, size); 719ac27a0ecSDave Kleikamp s->here->e_value_size = 0; 720ac27a0ecSDave Kleikamp s->here->e_value_offs = 0; 721ac27a0ecSDave Kleikamp min_offs += size; 722ac27a0ecSDave Kleikamp 723ac27a0ecSDave Kleikamp /* Adjust all value offsets. */ 724ac27a0ecSDave Kleikamp last = s->first; 725ac27a0ecSDave Kleikamp while (!IS_LAST_ENTRY(last)) { 726ac27a0ecSDave Kleikamp size_t o = le16_to_cpu(last->e_value_offs); 727ac27a0ecSDave Kleikamp if (!last->e_value_block && 728ac27a0ecSDave Kleikamp last->e_value_size && o < offs) 729ac27a0ecSDave Kleikamp last->e_value_offs = 730ac27a0ecSDave Kleikamp cpu_to_le16(o + size); 731617ba13bSMingming Cao last = EXT4_XATTR_NEXT(last); 732ac27a0ecSDave Kleikamp } 733ac27a0ecSDave Kleikamp } 734ac27a0ecSDave Kleikamp if (!i->value) { 735ac27a0ecSDave Kleikamp /* Remove the old name. */ 736617ba13bSMingming Cao size_t size = EXT4_XATTR_LEN(name_len); 737ac27a0ecSDave Kleikamp last = ENTRY((void *)last - size); 738ac27a0ecSDave Kleikamp memmove(s->here, (void *)s->here + size, 739ac27a0ecSDave Kleikamp (void *)last - (void *)s->here + sizeof(__u32)); 740ac27a0ecSDave Kleikamp memset(last, 0, size); 741ac27a0ecSDave Kleikamp } 742ac27a0ecSDave Kleikamp } 743ac27a0ecSDave Kleikamp 744ac27a0ecSDave Kleikamp if (i->value) { 745ac27a0ecSDave Kleikamp /* Insert the new value. */ 746ac27a0ecSDave Kleikamp s->here->e_value_size = cpu_to_le32(i->value_len); 747ac27a0ecSDave Kleikamp if (i->value_len) { 748617ba13bSMingming Cao size_t size = EXT4_XATTR_SIZE(i->value_len); 749ac27a0ecSDave Kleikamp void *val = s->base + min_offs - size; 750ac27a0ecSDave Kleikamp s->here->e_value_offs = cpu_to_le16(min_offs - size); 751bd9926e8STheodore Ts'o if (i->value == EXT4_ZERO_XATTR_VALUE) { 752bd9926e8STheodore Ts'o memset(val, 0, size); 753bd9926e8STheodore Ts'o } else { 754bd9926e8STheodore Ts'o /* Clear the pad bytes first. */ 755617ba13bSMingming Cao memset(val + size - EXT4_XATTR_PAD, 0, 756bd9926e8STheodore Ts'o EXT4_XATTR_PAD); 757ac27a0ecSDave Kleikamp memcpy(val, i->value, i->value_len); 758ac27a0ecSDave Kleikamp } 759ac27a0ecSDave Kleikamp } 760bd9926e8STheodore Ts'o } 761ac27a0ecSDave Kleikamp return 0; 762ac27a0ecSDave Kleikamp } 763ac27a0ecSDave Kleikamp 764617ba13bSMingming Cao struct ext4_xattr_block_find { 765617ba13bSMingming Cao struct ext4_xattr_search s; 766ac27a0ecSDave Kleikamp struct buffer_head *bh; 767ac27a0ecSDave Kleikamp }; 768ac27a0ecSDave Kleikamp 769ac27a0ecSDave Kleikamp static int 770617ba13bSMingming Cao ext4_xattr_block_find(struct inode *inode, struct ext4_xattr_info *i, 771617ba13bSMingming Cao struct ext4_xattr_block_find *bs) 772ac27a0ecSDave Kleikamp { 773ac27a0ecSDave Kleikamp struct super_block *sb = inode->i_sb; 774ac27a0ecSDave Kleikamp int error; 775ac27a0ecSDave Kleikamp 776ac27a0ecSDave Kleikamp ea_idebug(inode, "name=%d.%s, value=%p, value_len=%ld", 777ac27a0ecSDave Kleikamp i->name_index, i->name, i->value, (long)i->value_len); 778ac27a0ecSDave Kleikamp 779617ba13bSMingming Cao if (EXT4_I(inode)->i_file_acl) { 780ac27a0ecSDave Kleikamp /* The inode already has an extended attribute block. */ 781617ba13bSMingming Cao bs->bh = sb_bread(sb, EXT4_I(inode)->i_file_acl); 782ac27a0ecSDave Kleikamp error = -EIO; 783ac27a0ecSDave Kleikamp if (!bs->bh) 784ac27a0ecSDave Kleikamp goto cleanup; 785ac27a0ecSDave Kleikamp ea_bdebug(bs->bh, "b_count=%d, refcount=%d", 786ac27a0ecSDave Kleikamp atomic_read(&(bs->bh->b_count)), 787ac27a0ecSDave Kleikamp le32_to_cpu(BHDR(bs->bh)->h_refcount)); 788cc8e94fdSDarrick J. Wong if (ext4_xattr_check_block(inode, bs->bh)) { 78924676da4STheodore Ts'o EXT4_ERROR_INODE(inode, "bad block %llu", 79024676da4STheodore Ts'o EXT4_I(inode)->i_file_acl); 7916a797d27SDarrick J. Wong error = -EFSCORRUPTED; 792ac27a0ecSDave Kleikamp goto cleanup; 793ac27a0ecSDave Kleikamp } 794ac27a0ecSDave Kleikamp /* Find the named attribute. */ 795ac27a0ecSDave Kleikamp bs->s.base = BHDR(bs->bh); 796ac27a0ecSDave Kleikamp bs->s.first = BFIRST(bs->bh); 797ac27a0ecSDave Kleikamp bs->s.end = bs->bh->b_data + bs->bh->b_size; 798ac27a0ecSDave Kleikamp bs->s.here = bs->s.first; 799617ba13bSMingming Cao error = ext4_xattr_find_entry(&bs->s.here, i->name_index, 800ac27a0ecSDave Kleikamp i->name, bs->bh->b_size, 1); 801ac27a0ecSDave Kleikamp if (error && error != -ENODATA) 802ac27a0ecSDave Kleikamp goto cleanup; 803ac27a0ecSDave Kleikamp bs->s.not_found = error; 804ac27a0ecSDave Kleikamp } 805ac27a0ecSDave Kleikamp error = 0; 806ac27a0ecSDave Kleikamp 807ac27a0ecSDave Kleikamp cleanup: 808ac27a0ecSDave Kleikamp return error; 809ac27a0ecSDave Kleikamp } 810ac27a0ecSDave Kleikamp 811ac27a0ecSDave Kleikamp static int 812617ba13bSMingming Cao ext4_xattr_block_set(handle_t *handle, struct inode *inode, 813617ba13bSMingming Cao struct ext4_xattr_info *i, 814617ba13bSMingming Cao struct ext4_xattr_block_find *bs) 815ac27a0ecSDave Kleikamp { 816ac27a0ecSDave Kleikamp struct super_block *sb = inode->i_sb; 817ac27a0ecSDave Kleikamp struct buffer_head *new_bh = NULL; 818617ba13bSMingming Cao struct ext4_xattr_search *s = &bs->s; 8197a2508e1SJan Kara struct mb_cache_entry *ce = NULL; 8208a2bfdcbSMingming Cao int error = 0; 8217a2508e1SJan Kara struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); 822ac27a0ecSDave Kleikamp 823617ba13bSMingming Cao #define header(x) ((struct ext4_xattr_header *)(x)) 824ac27a0ecSDave Kleikamp 825ac27a0ecSDave Kleikamp if (i->value && i->value_len > sb->s_blocksize) 826ac27a0ecSDave Kleikamp return -ENOSPC; 827ac27a0ecSDave Kleikamp if (s->base) { 8285d601255Sliang xie BUFFER_TRACE(bs->bh, "get_write_access"); 8298a2bfdcbSMingming Cao error = ext4_journal_get_write_access(handle, bs->bh); 8308a2bfdcbSMingming Cao if (error) 8318a2bfdcbSMingming Cao goto cleanup; 8328a2bfdcbSMingming Cao lock_buffer(bs->bh); 8338a2bfdcbSMingming Cao 834ac27a0ecSDave Kleikamp if (header(s->base)->h_refcount == cpu_to_le32(1)) { 83582939d79SJan Kara __u32 hash = le32_to_cpu(BHDR(bs->bh)->h_hash); 83682939d79SJan Kara 83782939d79SJan Kara /* 83882939d79SJan Kara * This must happen under buffer lock for 83982939d79SJan Kara * ext4_xattr_block_set() to reliably detect modified 84082939d79SJan Kara * block 84182939d79SJan Kara */ 8427a2508e1SJan Kara mb_cache_entry_delete_block(ext4_mb_cache, hash, 84382939d79SJan Kara bs->bh->b_blocknr); 844ac27a0ecSDave Kleikamp ea_bdebug(bs->bh, "modifying in-place"); 845617ba13bSMingming Cao error = ext4_xattr_set_entry(i, s); 846ac27a0ecSDave Kleikamp if (!error) { 847ac27a0ecSDave Kleikamp if (!IS_LAST_ENTRY(s->first)) 848617ba13bSMingming Cao ext4_xattr_rehash(header(s->base), 849ac27a0ecSDave Kleikamp s->here); 8509c191f70ST Makphaibulchoke ext4_xattr_cache_insert(ext4_mb_cache, 8519c191f70ST Makphaibulchoke bs->bh); 852ac27a0ecSDave Kleikamp } 853ac27a0ecSDave Kleikamp unlock_buffer(bs->bh); 8546a797d27SDarrick J. Wong if (error == -EFSCORRUPTED) 855ac27a0ecSDave Kleikamp goto bad_block; 856ac27a0ecSDave Kleikamp if (!error) 857cc8e94fdSDarrick J. Wong error = ext4_handle_dirty_xattr_block(handle, 8580390131bSFrank Mayhar inode, 859ac27a0ecSDave Kleikamp bs->bh); 860ac27a0ecSDave Kleikamp if (error) 861ac27a0ecSDave Kleikamp goto cleanup; 862ac27a0ecSDave Kleikamp goto inserted; 863ac27a0ecSDave Kleikamp } else { 864ac27a0ecSDave Kleikamp int offset = (char *)s->here - bs->bh->b_data; 865ac27a0ecSDave Kleikamp 8668a2bfdcbSMingming Cao unlock_buffer(bs->bh); 867ac27a0ecSDave Kleikamp ea_bdebug(bs->bh, "cloning"); 868216553c4SJosef Bacik s->base = kmalloc(bs->bh->b_size, GFP_NOFS); 869ac27a0ecSDave Kleikamp error = -ENOMEM; 870ac27a0ecSDave Kleikamp if (s->base == NULL) 871ac27a0ecSDave Kleikamp goto cleanup; 872ac27a0ecSDave Kleikamp memcpy(s->base, BHDR(bs->bh), bs->bh->b_size); 873ac27a0ecSDave Kleikamp s->first = ENTRY(header(s->base)+1); 874ac27a0ecSDave Kleikamp header(s->base)->h_refcount = cpu_to_le32(1); 875ac27a0ecSDave Kleikamp s->here = ENTRY(s->base + offset); 876ac27a0ecSDave Kleikamp s->end = s->base + bs->bh->b_size; 877ac27a0ecSDave Kleikamp } 878ac27a0ecSDave Kleikamp } else { 879ac27a0ecSDave Kleikamp /* Allocate a buffer where we construct the new block. */ 880216553c4SJosef Bacik s->base = kzalloc(sb->s_blocksize, GFP_NOFS); 881ac27a0ecSDave Kleikamp /* assert(header == s->base) */ 882ac27a0ecSDave Kleikamp error = -ENOMEM; 883ac27a0ecSDave Kleikamp if (s->base == NULL) 884ac27a0ecSDave Kleikamp goto cleanup; 885617ba13bSMingming Cao header(s->base)->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC); 886ac27a0ecSDave Kleikamp header(s->base)->h_blocks = cpu_to_le32(1); 887ac27a0ecSDave Kleikamp header(s->base)->h_refcount = cpu_to_le32(1); 888ac27a0ecSDave Kleikamp s->first = ENTRY(header(s->base)+1); 889ac27a0ecSDave Kleikamp s->here = ENTRY(header(s->base)+1); 890ac27a0ecSDave Kleikamp s->end = s->base + sb->s_blocksize; 891ac27a0ecSDave Kleikamp } 892ac27a0ecSDave Kleikamp 893617ba13bSMingming Cao error = ext4_xattr_set_entry(i, s); 8946a797d27SDarrick J. Wong if (error == -EFSCORRUPTED) 895ac27a0ecSDave Kleikamp goto bad_block; 896ac27a0ecSDave Kleikamp if (error) 897ac27a0ecSDave Kleikamp goto cleanup; 898ac27a0ecSDave Kleikamp if (!IS_LAST_ENTRY(s->first)) 899617ba13bSMingming Cao ext4_xattr_rehash(header(s->base), s->here); 900ac27a0ecSDave Kleikamp 901ac27a0ecSDave Kleikamp inserted: 902ac27a0ecSDave Kleikamp if (!IS_LAST_ENTRY(s->first)) { 903617ba13bSMingming Cao new_bh = ext4_xattr_cache_find(inode, header(s->base), &ce); 904ac27a0ecSDave Kleikamp if (new_bh) { 905ac27a0ecSDave Kleikamp /* We found an identical block in the cache. */ 906ac27a0ecSDave Kleikamp if (new_bh == bs->bh) 907ac27a0ecSDave Kleikamp ea_bdebug(new_bh, "keeping"); 908ac27a0ecSDave Kleikamp else { 9096048c64bSAndreas Gruenbacher u32 ref; 9106048c64bSAndreas Gruenbacher 911ac27a0ecSDave Kleikamp /* The old block is released after updating 912ac27a0ecSDave Kleikamp the inode. */ 9131231b3a1SLukas Czerner error = dquot_alloc_block(inode, 9141231b3a1SLukas Czerner EXT4_C2B(EXT4_SB(sb), 1)); 9155dd4056dSChristoph Hellwig if (error) 916ac27a0ecSDave Kleikamp goto cleanup; 9175d601255Sliang xie BUFFER_TRACE(new_bh, "get_write_access"); 918617ba13bSMingming Cao error = ext4_journal_get_write_access(handle, 919ac27a0ecSDave Kleikamp new_bh); 920ac27a0ecSDave Kleikamp if (error) 921ac27a0ecSDave Kleikamp goto cleanup_dquot; 922ac27a0ecSDave Kleikamp lock_buffer(new_bh); 92382939d79SJan Kara /* 92482939d79SJan Kara * We have to be careful about races with 9256048c64bSAndreas Gruenbacher * freeing, rehashing or adding references to 9266048c64bSAndreas Gruenbacher * xattr block. Once we hold buffer lock xattr 9276048c64bSAndreas Gruenbacher * block's state is stable so we can check 9286048c64bSAndreas Gruenbacher * whether the block got freed / rehashed or 9296048c64bSAndreas Gruenbacher * not. Since we unhash mbcache entry under 9306048c64bSAndreas Gruenbacher * buffer lock when freeing / rehashing xattr 9316048c64bSAndreas Gruenbacher * block, checking whether entry is still 9326048c64bSAndreas Gruenbacher * hashed is reliable. Same rules hold for 9336048c64bSAndreas Gruenbacher * e_reusable handling. 93482939d79SJan Kara */ 9356048c64bSAndreas Gruenbacher if (hlist_bl_unhashed(&ce->e_hash_list) || 9366048c64bSAndreas Gruenbacher !ce->e_reusable) { 93782939d79SJan Kara /* 93882939d79SJan Kara * Undo everything and check mbcache 93982939d79SJan Kara * again. 94082939d79SJan Kara */ 94182939d79SJan Kara unlock_buffer(new_bh); 94282939d79SJan Kara dquot_free_block(inode, 94382939d79SJan Kara EXT4_C2B(EXT4_SB(sb), 94482939d79SJan Kara 1)); 94582939d79SJan Kara brelse(new_bh); 9467a2508e1SJan Kara mb_cache_entry_put(ext4_mb_cache, ce); 94782939d79SJan Kara ce = NULL; 94882939d79SJan Kara new_bh = NULL; 94982939d79SJan Kara goto inserted; 95082939d79SJan Kara } 9516048c64bSAndreas Gruenbacher ref = le32_to_cpu(BHDR(new_bh)->h_refcount) + 1; 9526048c64bSAndreas Gruenbacher BHDR(new_bh)->h_refcount = cpu_to_le32(ref); 9536048c64bSAndreas Gruenbacher if (ref >= EXT4_XATTR_REFCOUNT_MAX) 9546048c64bSAndreas Gruenbacher ce->e_reusable = 0; 955ac27a0ecSDave Kleikamp ea_bdebug(new_bh, "reusing; refcount now=%d", 9566048c64bSAndreas Gruenbacher ref); 957ac27a0ecSDave Kleikamp unlock_buffer(new_bh); 958cc8e94fdSDarrick J. Wong error = ext4_handle_dirty_xattr_block(handle, 9590390131bSFrank Mayhar inode, 960ac27a0ecSDave Kleikamp new_bh); 961ac27a0ecSDave Kleikamp if (error) 962ac27a0ecSDave Kleikamp goto cleanup_dquot; 963ac27a0ecSDave Kleikamp } 9647a2508e1SJan Kara mb_cache_entry_touch(ext4_mb_cache, ce); 9657a2508e1SJan Kara mb_cache_entry_put(ext4_mb_cache, ce); 966ac27a0ecSDave Kleikamp ce = NULL; 967ac27a0ecSDave Kleikamp } else if (bs->bh && s->base == bs->bh->b_data) { 968ac27a0ecSDave Kleikamp /* We were modifying this block in-place. */ 969ac27a0ecSDave Kleikamp ea_bdebug(bs->bh, "keeping this block"); 970ac27a0ecSDave Kleikamp new_bh = bs->bh; 971ac27a0ecSDave Kleikamp get_bh(new_bh); 972ac27a0ecSDave Kleikamp } else { 973ac27a0ecSDave Kleikamp /* We need to allocate a new block */ 974fb0a387dSEric Sandeen ext4_fsblk_t goal, block; 975fb0a387dSEric Sandeen 976fb0a387dSEric Sandeen goal = ext4_group_first_block_no(sb, 977d00a6d7bSAkinobu Mita EXT4_I(inode)->i_block_group); 978fb0a387dSEric Sandeen 979fb0a387dSEric Sandeen /* non-extent files can't have physical blocks past 2^32 */ 98012e9b892SDmitry Monakhov if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) 981fb0a387dSEric Sandeen goal = goal & EXT4_MAX_BLOCK_FILE_PHYS; 982fb0a387dSEric Sandeen 98355f020dbSAllison Henderson block = ext4_new_meta_blocks(handle, inode, goal, 0, 98455f020dbSAllison Henderson NULL, &error); 985ac27a0ecSDave Kleikamp if (error) 986ac27a0ecSDave Kleikamp goto cleanup; 987fb0a387dSEric Sandeen 98812e9b892SDmitry Monakhov if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) 989fb0a387dSEric Sandeen BUG_ON(block > EXT4_MAX_BLOCK_FILE_PHYS); 990fb0a387dSEric Sandeen 991ace36ad4SJoe Perches ea_idebug(inode, "creating block %llu", 992ace36ad4SJoe Perches (unsigned long long)block); 993ac27a0ecSDave Kleikamp 994ac27a0ecSDave Kleikamp new_bh = sb_getblk(sb, block); 995aebf0243SWang Shilong if (unlikely(!new_bh)) { 996860d21e2STheodore Ts'o error = -ENOMEM; 997ac27a0ecSDave Kleikamp getblk_failed: 9987dc57615SPeter Huewe ext4_free_blocks(handle, inode, NULL, block, 1, 999e6362609STheodore Ts'o EXT4_FREE_BLOCKS_METADATA); 1000ac27a0ecSDave Kleikamp goto cleanup; 1001ac27a0ecSDave Kleikamp } 1002ac27a0ecSDave Kleikamp lock_buffer(new_bh); 1003617ba13bSMingming Cao error = ext4_journal_get_create_access(handle, new_bh); 1004ac27a0ecSDave Kleikamp if (error) { 1005ac27a0ecSDave Kleikamp unlock_buffer(new_bh); 1006860d21e2STheodore Ts'o error = -EIO; 1007ac27a0ecSDave Kleikamp goto getblk_failed; 1008ac27a0ecSDave Kleikamp } 1009ac27a0ecSDave Kleikamp memcpy(new_bh->b_data, s->base, new_bh->b_size); 1010ac27a0ecSDave Kleikamp set_buffer_uptodate(new_bh); 1011ac27a0ecSDave Kleikamp unlock_buffer(new_bh); 10129c191f70ST Makphaibulchoke ext4_xattr_cache_insert(ext4_mb_cache, new_bh); 1013cc8e94fdSDarrick J. Wong error = ext4_handle_dirty_xattr_block(handle, 10140390131bSFrank Mayhar inode, new_bh); 1015ac27a0ecSDave Kleikamp if (error) 1016ac27a0ecSDave Kleikamp goto cleanup; 1017ac27a0ecSDave Kleikamp } 1018ac27a0ecSDave Kleikamp } 1019ac27a0ecSDave Kleikamp 1020ac27a0ecSDave Kleikamp /* Update the inode. */ 1021617ba13bSMingming Cao EXT4_I(inode)->i_file_acl = new_bh ? new_bh->b_blocknr : 0; 1022ac27a0ecSDave Kleikamp 1023ac27a0ecSDave Kleikamp /* Drop the previous xattr block. */ 1024ac27a0ecSDave Kleikamp if (bs->bh && bs->bh != new_bh) 1025617ba13bSMingming Cao ext4_xattr_release_block(handle, inode, bs->bh); 1026ac27a0ecSDave Kleikamp error = 0; 1027ac27a0ecSDave Kleikamp 1028ac27a0ecSDave Kleikamp cleanup: 1029ac27a0ecSDave Kleikamp if (ce) 10307a2508e1SJan Kara mb_cache_entry_put(ext4_mb_cache, ce); 1031ac27a0ecSDave Kleikamp brelse(new_bh); 1032ac27a0ecSDave Kleikamp if (!(bs->bh && s->base == bs->bh->b_data)) 1033ac27a0ecSDave Kleikamp kfree(s->base); 1034ac27a0ecSDave Kleikamp 1035ac27a0ecSDave Kleikamp return error; 1036ac27a0ecSDave Kleikamp 1037ac27a0ecSDave Kleikamp cleanup_dquot: 10381231b3a1SLukas Czerner dquot_free_block(inode, EXT4_C2B(EXT4_SB(sb), 1)); 1039ac27a0ecSDave Kleikamp goto cleanup; 1040ac27a0ecSDave Kleikamp 1041ac27a0ecSDave Kleikamp bad_block: 104224676da4STheodore Ts'o EXT4_ERROR_INODE(inode, "bad block %llu", 104324676da4STheodore Ts'o EXT4_I(inode)->i_file_acl); 1044ac27a0ecSDave Kleikamp goto cleanup; 1045ac27a0ecSDave Kleikamp 1046ac27a0ecSDave Kleikamp #undef header 1047ac27a0ecSDave Kleikamp } 1048ac27a0ecSDave Kleikamp 1049879b3825STao Ma int ext4_xattr_ibody_find(struct inode *inode, struct ext4_xattr_info *i, 1050617ba13bSMingming Cao struct ext4_xattr_ibody_find *is) 1051ac27a0ecSDave Kleikamp { 1052617ba13bSMingming Cao struct ext4_xattr_ibody_header *header; 1053617ba13bSMingming Cao struct ext4_inode *raw_inode; 1054ac27a0ecSDave Kleikamp int error; 1055ac27a0ecSDave Kleikamp 1056617ba13bSMingming Cao if (EXT4_I(inode)->i_extra_isize == 0) 1057ac27a0ecSDave Kleikamp return 0; 1058617ba13bSMingming Cao raw_inode = ext4_raw_inode(&is->iloc); 1059ac27a0ecSDave Kleikamp header = IHDR(inode, raw_inode); 1060ac27a0ecSDave Kleikamp is->s.base = is->s.first = IFIRST(header); 1061ac27a0ecSDave Kleikamp is->s.here = is->s.first; 1062617ba13bSMingming Cao is->s.end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; 106319f5fb7aSTheodore Ts'o if (ext4_test_inode_state(inode, EXT4_STATE_XATTR)) { 1064*9e92f48cSTheodore Ts'o error = xattr_check_inode(inode, header, is->s.end); 1065ac27a0ecSDave Kleikamp if (error) 1066ac27a0ecSDave Kleikamp return error; 1067ac27a0ecSDave Kleikamp /* Find the named attribute. */ 1068617ba13bSMingming Cao error = ext4_xattr_find_entry(&is->s.here, i->name_index, 1069ac27a0ecSDave Kleikamp i->name, is->s.end - 1070ac27a0ecSDave Kleikamp (void *)is->s.base, 0); 1071ac27a0ecSDave Kleikamp if (error && error != -ENODATA) 1072ac27a0ecSDave Kleikamp return error; 1073ac27a0ecSDave Kleikamp is->s.not_found = error; 1074ac27a0ecSDave Kleikamp } 1075ac27a0ecSDave Kleikamp return 0; 1076ac27a0ecSDave Kleikamp } 1077ac27a0ecSDave Kleikamp 10780d812f77STao Ma int ext4_xattr_ibody_inline_set(handle_t *handle, struct inode *inode, 10790d812f77STao Ma struct ext4_xattr_info *i, 10800d812f77STao Ma struct ext4_xattr_ibody_find *is) 10810d812f77STao Ma { 10820d812f77STao Ma struct ext4_xattr_ibody_header *header; 10830d812f77STao Ma struct ext4_xattr_search *s = &is->s; 10840d812f77STao Ma int error; 10850d812f77STao Ma 10860d812f77STao Ma if (EXT4_I(inode)->i_extra_isize == 0) 10870d812f77STao Ma return -ENOSPC; 10880d812f77STao Ma error = ext4_xattr_set_entry(i, s); 10890d812f77STao Ma if (error) { 10900d812f77STao Ma if (error == -ENOSPC && 10910d812f77STao Ma ext4_has_inline_data(inode)) { 10920d812f77STao Ma error = ext4_try_to_evict_inline_data(handle, inode, 10930d812f77STao Ma EXT4_XATTR_LEN(strlen(i->name) + 10940d812f77STao Ma EXT4_XATTR_SIZE(i->value_len))); 10950d812f77STao Ma if (error) 10960d812f77STao Ma return error; 10970d812f77STao Ma error = ext4_xattr_ibody_find(inode, i, is); 10980d812f77STao Ma if (error) 10990d812f77STao Ma return error; 11000d812f77STao Ma error = ext4_xattr_set_entry(i, s); 11010d812f77STao Ma } 11020d812f77STao Ma if (error) 11030d812f77STao Ma return error; 11040d812f77STao Ma } 11050d812f77STao Ma header = IHDR(inode, ext4_raw_inode(&is->iloc)); 11060d812f77STao Ma if (!IS_LAST_ENTRY(s->first)) { 11070d812f77STao Ma header->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC); 11080d812f77STao Ma ext4_set_inode_state(inode, EXT4_STATE_XATTR); 11090d812f77STao Ma } else { 11100d812f77STao Ma header->h_magic = cpu_to_le32(0); 11110d812f77STao Ma ext4_clear_inode_state(inode, EXT4_STATE_XATTR); 11120d812f77STao Ma } 11130d812f77STao Ma return 0; 11140d812f77STao Ma } 11150d812f77STao Ma 11160d812f77STao Ma static int ext4_xattr_ibody_set(handle_t *handle, struct inode *inode, 1117617ba13bSMingming Cao struct ext4_xattr_info *i, 1118617ba13bSMingming Cao struct ext4_xattr_ibody_find *is) 1119ac27a0ecSDave Kleikamp { 1120617ba13bSMingming Cao struct ext4_xattr_ibody_header *header; 1121617ba13bSMingming Cao struct ext4_xattr_search *s = &is->s; 1122ac27a0ecSDave Kleikamp int error; 1123ac27a0ecSDave Kleikamp 1124617ba13bSMingming Cao if (EXT4_I(inode)->i_extra_isize == 0) 1125ac27a0ecSDave Kleikamp return -ENOSPC; 1126617ba13bSMingming Cao error = ext4_xattr_set_entry(i, s); 1127ac27a0ecSDave Kleikamp if (error) 1128ac27a0ecSDave Kleikamp return error; 1129617ba13bSMingming Cao header = IHDR(inode, ext4_raw_inode(&is->iloc)); 1130ac27a0ecSDave Kleikamp if (!IS_LAST_ENTRY(s->first)) { 1131617ba13bSMingming Cao header->h_magic = cpu_to_le32(EXT4_XATTR_MAGIC); 113219f5fb7aSTheodore Ts'o ext4_set_inode_state(inode, EXT4_STATE_XATTR); 1133ac27a0ecSDave Kleikamp } else { 1134ac27a0ecSDave Kleikamp header->h_magic = cpu_to_le32(0); 113519f5fb7aSTheodore Ts'o ext4_clear_inode_state(inode, EXT4_STATE_XATTR); 1136ac27a0ecSDave Kleikamp } 1137ac27a0ecSDave Kleikamp return 0; 1138ac27a0ecSDave Kleikamp } 1139ac27a0ecSDave Kleikamp 11403fd16462SJan Kara static int ext4_xattr_value_same(struct ext4_xattr_search *s, 11413fd16462SJan Kara struct ext4_xattr_info *i) 11423fd16462SJan Kara { 11433fd16462SJan Kara void *value; 11443fd16462SJan Kara 11453fd16462SJan Kara if (le32_to_cpu(s->here->e_value_size) != i->value_len) 11463fd16462SJan Kara return 0; 11473fd16462SJan Kara value = ((void *)s->base) + le16_to_cpu(s->here->e_value_offs); 11483fd16462SJan Kara return !memcmp(value, i->value, i->value_len); 11493fd16462SJan Kara } 11503fd16462SJan Kara 1151ac27a0ecSDave Kleikamp /* 1152617ba13bSMingming Cao * ext4_xattr_set_handle() 1153ac27a0ecSDave Kleikamp * 11546e9510b0SWang Sheng-Hui * Create, replace or remove an extended attribute for this inode. Value 1155ac27a0ecSDave Kleikamp * is NULL to remove an existing extended attribute, and non-NULL to 1156ac27a0ecSDave Kleikamp * either replace an existing extended attribute, or create a new extended 1157ac27a0ecSDave Kleikamp * attribute. The flags XATTR_REPLACE and XATTR_CREATE 1158ac27a0ecSDave Kleikamp * specify that an extended attribute must exist and must not exist 1159ac27a0ecSDave Kleikamp * previous to the call, respectively. 1160ac27a0ecSDave Kleikamp * 1161ac27a0ecSDave Kleikamp * Returns 0, or a negative error number on failure. 1162ac27a0ecSDave Kleikamp */ 1163ac27a0ecSDave Kleikamp int 1164617ba13bSMingming Cao ext4_xattr_set_handle(handle_t *handle, struct inode *inode, int name_index, 1165ac27a0ecSDave Kleikamp const char *name, const void *value, size_t value_len, 1166ac27a0ecSDave Kleikamp int flags) 1167ac27a0ecSDave Kleikamp { 1168617ba13bSMingming Cao struct ext4_xattr_info i = { 1169ac27a0ecSDave Kleikamp .name_index = name_index, 1170ac27a0ecSDave Kleikamp .name = name, 1171ac27a0ecSDave Kleikamp .value = value, 1172ac27a0ecSDave Kleikamp .value_len = value_len, 1173ac27a0ecSDave Kleikamp 1174ac27a0ecSDave Kleikamp }; 1175617ba13bSMingming Cao struct ext4_xattr_ibody_find is = { 1176ac27a0ecSDave Kleikamp .s = { .not_found = -ENODATA, }, 1177ac27a0ecSDave Kleikamp }; 1178617ba13bSMingming Cao struct ext4_xattr_block_find bs = { 1179ac27a0ecSDave Kleikamp .s = { .not_found = -ENODATA, }, 1180ac27a0ecSDave Kleikamp }; 11814d20c685SKalpak Shah unsigned long no_expand; 1182ac27a0ecSDave Kleikamp int error; 1183ac27a0ecSDave Kleikamp 1184ac27a0ecSDave Kleikamp if (!name) 1185ac27a0ecSDave Kleikamp return -EINVAL; 1186ac27a0ecSDave Kleikamp if (strlen(name) > 255) 1187ac27a0ecSDave Kleikamp return -ERANGE; 1188617ba13bSMingming Cao down_write(&EXT4_I(inode)->xattr_sem); 118919f5fb7aSTheodore Ts'o no_expand = ext4_test_inode_state(inode, EXT4_STATE_NO_EXPAND); 119019f5fb7aSTheodore Ts'o ext4_set_inode_state(inode, EXT4_STATE_NO_EXPAND); 11914d20c685SKalpak Shah 119266543617SEric Sandeen error = ext4_reserve_inode_write(handle, inode, &is.iloc); 119386ebfd08SEric Sandeen if (error) 119486ebfd08SEric Sandeen goto cleanup; 119586ebfd08SEric Sandeen 119619f5fb7aSTheodore Ts'o if (ext4_test_inode_state(inode, EXT4_STATE_NEW)) { 1197617ba13bSMingming Cao struct ext4_inode *raw_inode = ext4_raw_inode(&is.iloc); 1198617ba13bSMingming Cao memset(raw_inode, 0, EXT4_SB(inode->i_sb)->s_inode_size); 119919f5fb7aSTheodore Ts'o ext4_clear_inode_state(inode, EXT4_STATE_NEW); 1200ac27a0ecSDave Kleikamp } 1201ac27a0ecSDave Kleikamp 1202617ba13bSMingming Cao error = ext4_xattr_ibody_find(inode, &i, &is); 1203ac27a0ecSDave Kleikamp if (error) 1204ac27a0ecSDave Kleikamp goto cleanup; 1205ac27a0ecSDave Kleikamp if (is.s.not_found) 1206617ba13bSMingming Cao error = ext4_xattr_block_find(inode, &i, &bs); 1207ac27a0ecSDave Kleikamp if (error) 1208ac27a0ecSDave Kleikamp goto cleanup; 1209ac27a0ecSDave Kleikamp if (is.s.not_found && bs.s.not_found) { 1210ac27a0ecSDave Kleikamp error = -ENODATA; 1211ac27a0ecSDave Kleikamp if (flags & XATTR_REPLACE) 1212ac27a0ecSDave Kleikamp goto cleanup; 1213ac27a0ecSDave Kleikamp error = 0; 1214ac27a0ecSDave Kleikamp if (!value) 1215ac27a0ecSDave Kleikamp goto cleanup; 1216ac27a0ecSDave Kleikamp } else { 1217ac27a0ecSDave Kleikamp error = -EEXIST; 1218ac27a0ecSDave Kleikamp if (flags & XATTR_CREATE) 1219ac27a0ecSDave Kleikamp goto cleanup; 1220ac27a0ecSDave Kleikamp } 1221ac27a0ecSDave Kleikamp if (!value) { 1222ac27a0ecSDave Kleikamp if (!is.s.not_found) 1223617ba13bSMingming Cao error = ext4_xattr_ibody_set(handle, inode, &i, &is); 1224ac27a0ecSDave Kleikamp else if (!bs.s.not_found) 1225617ba13bSMingming Cao error = ext4_xattr_block_set(handle, inode, &i, &bs); 1226ac27a0ecSDave Kleikamp } else { 12273fd16462SJan Kara error = 0; 12283fd16462SJan Kara /* Xattr value did not change? Save us some work and bail out */ 12293fd16462SJan Kara if (!is.s.not_found && ext4_xattr_value_same(&is.s, &i)) 12303fd16462SJan Kara goto cleanup; 12313fd16462SJan Kara if (!bs.s.not_found && ext4_xattr_value_same(&bs.s, &i)) 12323fd16462SJan Kara goto cleanup; 12333fd16462SJan Kara 1234617ba13bSMingming Cao error = ext4_xattr_ibody_set(handle, inode, &i, &is); 1235ac27a0ecSDave Kleikamp if (!error && !bs.s.not_found) { 1236ac27a0ecSDave Kleikamp i.value = NULL; 1237617ba13bSMingming Cao error = ext4_xattr_block_set(handle, inode, &i, &bs); 1238ac27a0ecSDave Kleikamp } else if (error == -ENOSPC) { 12397e01c8e5STiger Yang if (EXT4_I(inode)->i_file_acl && !bs.s.base) { 12407e01c8e5STiger Yang error = ext4_xattr_block_find(inode, &i, &bs); 12417e01c8e5STiger Yang if (error) 12427e01c8e5STiger Yang goto cleanup; 12437e01c8e5STiger Yang } 1244617ba13bSMingming Cao error = ext4_xattr_block_set(handle, inode, &i, &bs); 1245ac27a0ecSDave Kleikamp if (error) 1246ac27a0ecSDave Kleikamp goto cleanup; 1247ac27a0ecSDave Kleikamp if (!is.s.not_found) { 1248ac27a0ecSDave Kleikamp i.value = NULL; 1249617ba13bSMingming Cao error = ext4_xattr_ibody_set(handle, inode, &i, 1250ac27a0ecSDave Kleikamp &is); 1251ac27a0ecSDave Kleikamp } 1252ac27a0ecSDave Kleikamp } 1253ac27a0ecSDave Kleikamp } 1254ac27a0ecSDave Kleikamp if (!error) { 1255617ba13bSMingming Cao ext4_xattr_update_super_block(handle, inode->i_sb); 1256ef7f3835SKalpak Shah inode->i_ctime = ext4_current_time(inode); 12576dd4ee7cSKalpak Shah if (!value) 125819f5fb7aSTheodore Ts'o ext4_clear_inode_state(inode, EXT4_STATE_NO_EXPAND); 1259617ba13bSMingming Cao error = ext4_mark_iloc_dirty(handle, inode, &is.iloc); 1260ac27a0ecSDave Kleikamp /* 1261617ba13bSMingming Cao * The bh is consumed by ext4_mark_iloc_dirty, even with 1262ac27a0ecSDave Kleikamp * error != 0. 1263ac27a0ecSDave Kleikamp */ 1264ac27a0ecSDave Kleikamp is.iloc.bh = NULL; 1265ac27a0ecSDave Kleikamp if (IS_SYNC(inode)) 12660390131bSFrank Mayhar ext4_handle_sync(handle); 1267ac27a0ecSDave Kleikamp } 1268ac27a0ecSDave Kleikamp 1269ac27a0ecSDave Kleikamp cleanup: 1270ac27a0ecSDave Kleikamp brelse(is.iloc.bh); 1271ac27a0ecSDave Kleikamp brelse(bs.bh); 12724d20c685SKalpak Shah if (no_expand == 0) 127319f5fb7aSTheodore Ts'o ext4_clear_inode_state(inode, EXT4_STATE_NO_EXPAND); 1274617ba13bSMingming Cao up_write(&EXT4_I(inode)->xattr_sem); 1275ac27a0ecSDave Kleikamp return error; 1276ac27a0ecSDave Kleikamp } 1277ac27a0ecSDave Kleikamp 1278ac27a0ecSDave Kleikamp /* 1279617ba13bSMingming Cao * ext4_xattr_set() 1280ac27a0ecSDave Kleikamp * 1281617ba13bSMingming Cao * Like ext4_xattr_set_handle, but start from an inode. This extended 1282ac27a0ecSDave Kleikamp * attribute modification is a filesystem transaction by itself. 1283ac27a0ecSDave Kleikamp * 1284ac27a0ecSDave Kleikamp * Returns 0, or a negative error number on failure. 1285ac27a0ecSDave Kleikamp */ 1286ac27a0ecSDave Kleikamp int 1287617ba13bSMingming Cao ext4_xattr_set(struct inode *inode, int name_index, const char *name, 1288ac27a0ecSDave Kleikamp const void *value, size_t value_len, int flags) 1289ac27a0ecSDave Kleikamp { 1290ac27a0ecSDave Kleikamp handle_t *handle; 1291ac27a0ecSDave Kleikamp int error, retries = 0; 129295eaefbdSTheodore Ts'o int credits = ext4_jbd2_credits_xattr(inode); 1293ac27a0ecSDave Kleikamp 1294ac27a0ecSDave Kleikamp retry: 12959924a92aSTheodore Ts'o handle = ext4_journal_start(inode, EXT4_HT_XATTR, credits); 1296ac27a0ecSDave Kleikamp if (IS_ERR(handle)) { 1297ac27a0ecSDave Kleikamp error = PTR_ERR(handle); 1298ac27a0ecSDave Kleikamp } else { 1299ac27a0ecSDave Kleikamp int error2; 1300ac27a0ecSDave Kleikamp 1301617ba13bSMingming Cao error = ext4_xattr_set_handle(handle, inode, name_index, name, 1302ac27a0ecSDave Kleikamp value, value_len, flags); 1303617ba13bSMingming Cao error2 = ext4_journal_stop(handle); 1304ac27a0ecSDave Kleikamp if (error == -ENOSPC && 1305617ba13bSMingming Cao ext4_should_retry_alloc(inode->i_sb, &retries)) 1306ac27a0ecSDave Kleikamp goto retry; 1307ac27a0ecSDave Kleikamp if (error == 0) 1308ac27a0ecSDave Kleikamp error = error2; 1309ac27a0ecSDave Kleikamp } 1310ac27a0ecSDave Kleikamp 1311ac27a0ecSDave Kleikamp return error; 1312ac27a0ecSDave Kleikamp } 1313ac27a0ecSDave Kleikamp 1314ac27a0ecSDave Kleikamp /* 13156dd4ee7cSKalpak Shah * Shift the EA entries in the inode to create space for the increased 13166dd4ee7cSKalpak Shah * i_extra_isize. 13176dd4ee7cSKalpak Shah */ 13186dd4ee7cSKalpak Shah static void ext4_xattr_shift_entries(struct ext4_xattr_entry *entry, 13196dd4ee7cSKalpak Shah int value_offs_shift, void *to, 13206dd4ee7cSKalpak Shah void *from, size_t n, int blocksize) 13216dd4ee7cSKalpak Shah { 13226dd4ee7cSKalpak Shah struct ext4_xattr_entry *last = entry; 13236dd4ee7cSKalpak Shah int new_offs; 13246dd4ee7cSKalpak Shah 13256dd4ee7cSKalpak Shah /* Adjust the value offsets of the entries */ 13266dd4ee7cSKalpak Shah for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { 13276dd4ee7cSKalpak Shah if (!last->e_value_block && last->e_value_size) { 13286dd4ee7cSKalpak Shah new_offs = le16_to_cpu(last->e_value_offs) + 13296dd4ee7cSKalpak Shah value_offs_shift; 13306dd4ee7cSKalpak Shah BUG_ON(new_offs + le32_to_cpu(last->e_value_size) 13316dd4ee7cSKalpak Shah > blocksize); 13326dd4ee7cSKalpak Shah last->e_value_offs = cpu_to_le16(new_offs); 13336dd4ee7cSKalpak Shah } 13346dd4ee7cSKalpak Shah } 13356dd4ee7cSKalpak Shah /* Shift the entries by n bytes */ 13366dd4ee7cSKalpak Shah memmove(to, from, n); 13376dd4ee7cSKalpak Shah } 13386dd4ee7cSKalpak Shah 13396dd4ee7cSKalpak Shah /* 13406dd4ee7cSKalpak Shah * Expand an inode by new_extra_isize bytes when EAs are present. 13416dd4ee7cSKalpak Shah * Returns 0 on success or negative error number on failure. 13426dd4ee7cSKalpak Shah */ 13436dd4ee7cSKalpak Shah int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize, 13446dd4ee7cSKalpak Shah struct ext4_inode *raw_inode, handle_t *handle) 13456dd4ee7cSKalpak Shah { 13466dd4ee7cSKalpak Shah struct ext4_xattr_ibody_header *header; 13476dd4ee7cSKalpak Shah struct ext4_xattr_entry *entry, *last, *first; 13486dd4ee7cSKalpak Shah struct buffer_head *bh = NULL; 13496dd4ee7cSKalpak Shah struct ext4_xattr_ibody_find *is = NULL; 13506dd4ee7cSKalpak Shah struct ext4_xattr_block_find *bs = NULL; 13516dd4ee7cSKalpak Shah char *buffer = NULL, *b_entry_name = NULL; 13526dd4ee7cSKalpak Shah size_t min_offs, free; 13537b1b2c1bSTheodore Ts'o int total_ino; 13546dd4ee7cSKalpak Shah void *base, *start, *end; 13556dd4ee7cSKalpak Shah int extra_isize = 0, error = 0, tried_min_extra_isize = 0; 1356ac39849dSAneesh Kumar K.V int s_min_extra_isize = le16_to_cpu(EXT4_SB(inode->i_sb)->s_es->s_min_extra_isize); 13576dd4ee7cSKalpak Shah 13586dd4ee7cSKalpak Shah down_write(&EXT4_I(inode)->xattr_sem); 13596dd4ee7cSKalpak Shah retry: 13606dd4ee7cSKalpak Shah if (EXT4_I(inode)->i_extra_isize >= new_extra_isize) { 13616dd4ee7cSKalpak Shah up_write(&EXT4_I(inode)->xattr_sem); 13626dd4ee7cSKalpak Shah return 0; 13636dd4ee7cSKalpak Shah } 13646dd4ee7cSKalpak Shah 13656dd4ee7cSKalpak Shah header = IHDR(inode, raw_inode); 13666dd4ee7cSKalpak Shah entry = IFIRST(header); 13676dd4ee7cSKalpak Shah 13686dd4ee7cSKalpak Shah /* 13696dd4ee7cSKalpak Shah * Check if enough free space is available in the inode to shift the 13706dd4ee7cSKalpak Shah * entries ahead by new_extra_isize. 13716dd4ee7cSKalpak Shah */ 13726dd4ee7cSKalpak Shah 13736dd4ee7cSKalpak Shah base = start = entry; 13746dd4ee7cSKalpak Shah end = (void *)raw_inode + EXT4_SB(inode->i_sb)->s_inode_size; 13756dd4ee7cSKalpak Shah min_offs = end - base; 13766dd4ee7cSKalpak Shah last = entry; 13776dd4ee7cSKalpak Shah total_ino = sizeof(struct ext4_xattr_ibody_header); 13786dd4ee7cSKalpak Shah 1379*9e92f48cSTheodore Ts'o error = xattr_check_inode(inode, header, end); 1380*9e92f48cSTheodore Ts'o if (error) 1381*9e92f48cSTheodore Ts'o goto cleanup; 1382*9e92f48cSTheodore Ts'o 13836dd4ee7cSKalpak Shah free = ext4_xattr_free_space(last, &min_offs, base, &total_ino); 13846dd4ee7cSKalpak Shah if (free >= new_extra_isize) { 13856dd4ee7cSKalpak Shah entry = IFIRST(header); 13866dd4ee7cSKalpak Shah ext4_xattr_shift_entries(entry, EXT4_I(inode)->i_extra_isize 13876dd4ee7cSKalpak Shah - new_extra_isize, (void *)raw_inode + 13886dd4ee7cSKalpak Shah EXT4_GOOD_OLD_INODE_SIZE + new_extra_isize, 13896dd4ee7cSKalpak Shah (void *)header, total_ino, 13906dd4ee7cSKalpak Shah inode->i_sb->s_blocksize); 13916dd4ee7cSKalpak Shah EXT4_I(inode)->i_extra_isize = new_extra_isize; 13926dd4ee7cSKalpak Shah error = 0; 13936dd4ee7cSKalpak Shah goto cleanup; 13946dd4ee7cSKalpak Shah } 13956dd4ee7cSKalpak Shah 13966dd4ee7cSKalpak Shah /* 13976dd4ee7cSKalpak Shah * Enough free space isn't available in the inode, check if 13986dd4ee7cSKalpak Shah * EA block can hold new_extra_isize bytes. 13996dd4ee7cSKalpak Shah */ 14006dd4ee7cSKalpak Shah if (EXT4_I(inode)->i_file_acl) { 14016dd4ee7cSKalpak Shah bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); 14026dd4ee7cSKalpak Shah error = -EIO; 14036dd4ee7cSKalpak Shah if (!bh) 14046dd4ee7cSKalpak Shah goto cleanup; 1405cc8e94fdSDarrick J. Wong if (ext4_xattr_check_block(inode, bh)) { 140624676da4STheodore Ts'o EXT4_ERROR_INODE(inode, "bad block %llu", 140724676da4STheodore Ts'o EXT4_I(inode)->i_file_acl); 14086a797d27SDarrick J. Wong error = -EFSCORRUPTED; 14096dd4ee7cSKalpak Shah goto cleanup; 14106dd4ee7cSKalpak Shah } 14116dd4ee7cSKalpak Shah base = BHDR(bh); 14126dd4ee7cSKalpak Shah first = BFIRST(bh); 14136dd4ee7cSKalpak Shah end = bh->b_data + bh->b_size; 14146dd4ee7cSKalpak Shah min_offs = end - base; 14157b1b2c1bSTheodore Ts'o free = ext4_xattr_free_space(first, &min_offs, base, NULL); 14166dd4ee7cSKalpak Shah if (free < new_extra_isize) { 14176dd4ee7cSKalpak Shah if (!tried_min_extra_isize && s_min_extra_isize) { 14186dd4ee7cSKalpak Shah tried_min_extra_isize++; 14196dd4ee7cSKalpak Shah new_extra_isize = s_min_extra_isize; 14206dd4ee7cSKalpak Shah brelse(bh); 14216dd4ee7cSKalpak Shah goto retry; 14226dd4ee7cSKalpak Shah } 14236dd4ee7cSKalpak Shah error = -1; 14246dd4ee7cSKalpak Shah goto cleanup; 14256dd4ee7cSKalpak Shah } 14266dd4ee7cSKalpak Shah } else { 14276dd4ee7cSKalpak Shah free = inode->i_sb->s_blocksize; 14286dd4ee7cSKalpak Shah } 14296dd4ee7cSKalpak Shah 14306dd4ee7cSKalpak Shah while (new_extra_isize > 0) { 14316dd4ee7cSKalpak Shah size_t offs, size, entry_size; 14326dd4ee7cSKalpak Shah struct ext4_xattr_entry *small_entry = NULL; 14336dd4ee7cSKalpak Shah struct ext4_xattr_info i = { 14346dd4ee7cSKalpak Shah .value = NULL, 14356dd4ee7cSKalpak Shah .value_len = 0, 14366dd4ee7cSKalpak Shah }; 14376dd4ee7cSKalpak Shah unsigned int total_size; /* EA entry size + value size */ 14386dd4ee7cSKalpak Shah unsigned int shift_bytes; /* No. of bytes to shift EAs by? */ 14396dd4ee7cSKalpak Shah unsigned int min_total_size = ~0U; 14406dd4ee7cSKalpak Shah 14416dd4ee7cSKalpak Shah is = kzalloc(sizeof(struct ext4_xattr_ibody_find), GFP_NOFS); 14426dd4ee7cSKalpak Shah bs = kzalloc(sizeof(struct ext4_xattr_block_find), GFP_NOFS); 14436dd4ee7cSKalpak Shah if (!is || !bs) { 14446dd4ee7cSKalpak Shah error = -ENOMEM; 14456dd4ee7cSKalpak Shah goto cleanup; 14466dd4ee7cSKalpak Shah } 14476dd4ee7cSKalpak Shah 14486dd4ee7cSKalpak Shah is->s.not_found = -ENODATA; 14496dd4ee7cSKalpak Shah bs->s.not_found = -ENODATA; 14506dd4ee7cSKalpak Shah is->iloc.bh = NULL; 14516dd4ee7cSKalpak Shah bs->bh = NULL; 14526dd4ee7cSKalpak Shah 14536dd4ee7cSKalpak Shah last = IFIRST(header); 14546dd4ee7cSKalpak Shah /* Find the entry best suited to be pushed into EA block */ 14556dd4ee7cSKalpak Shah entry = NULL; 14566dd4ee7cSKalpak Shah for (; !IS_LAST_ENTRY(last); last = EXT4_XATTR_NEXT(last)) { 14576dd4ee7cSKalpak Shah total_size = 14586dd4ee7cSKalpak Shah EXT4_XATTR_SIZE(le32_to_cpu(last->e_value_size)) + 14596dd4ee7cSKalpak Shah EXT4_XATTR_LEN(last->e_name_len); 14606dd4ee7cSKalpak Shah if (total_size <= free && total_size < min_total_size) { 14616dd4ee7cSKalpak Shah if (total_size < new_extra_isize) { 14626dd4ee7cSKalpak Shah small_entry = last; 14636dd4ee7cSKalpak Shah } else { 14646dd4ee7cSKalpak Shah entry = last; 14656dd4ee7cSKalpak Shah min_total_size = total_size; 14666dd4ee7cSKalpak Shah } 14676dd4ee7cSKalpak Shah } 14686dd4ee7cSKalpak Shah } 14696dd4ee7cSKalpak Shah 14706dd4ee7cSKalpak Shah if (entry == NULL) { 14716dd4ee7cSKalpak Shah if (small_entry) { 14726dd4ee7cSKalpak Shah entry = small_entry; 14736dd4ee7cSKalpak Shah } else { 14746dd4ee7cSKalpak Shah if (!tried_min_extra_isize && 14756dd4ee7cSKalpak Shah s_min_extra_isize) { 14766dd4ee7cSKalpak Shah tried_min_extra_isize++; 14776dd4ee7cSKalpak Shah new_extra_isize = s_min_extra_isize; 14786e4ea8e3SDave Jones kfree(is); is = NULL; 14796e4ea8e3SDave Jones kfree(bs); bs = NULL; 1480dcb9917bSTheodore Ts'o brelse(bh); 14816dd4ee7cSKalpak Shah goto retry; 14826dd4ee7cSKalpak Shah } 14836dd4ee7cSKalpak Shah error = -1; 14846dd4ee7cSKalpak Shah goto cleanup; 14856dd4ee7cSKalpak Shah } 14866dd4ee7cSKalpak Shah } 14876dd4ee7cSKalpak Shah offs = le16_to_cpu(entry->e_value_offs); 14886dd4ee7cSKalpak Shah size = le32_to_cpu(entry->e_value_size); 14896dd4ee7cSKalpak Shah entry_size = EXT4_XATTR_LEN(entry->e_name_len); 14906dd4ee7cSKalpak Shah i.name_index = entry->e_name_index, 14916dd4ee7cSKalpak Shah buffer = kmalloc(EXT4_XATTR_SIZE(size), GFP_NOFS); 14926dd4ee7cSKalpak Shah b_entry_name = kmalloc(entry->e_name_len + 1, GFP_NOFS); 14936dd4ee7cSKalpak Shah if (!buffer || !b_entry_name) { 14946dd4ee7cSKalpak Shah error = -ENOMEM; 14956dd4ee7cSKalpak Shah goto cleanup; 14966dd4ee7cSKalpak Shah } 14976dd4ee7cSKalpak Shah /* Save the entry name and the entry value */ 14986dd4ee7cSKalpak Shah memcpy(buffer, (void *)IFIRST(header) + offs, 14996dd4ee7cSKalpak Shah EXT4_XATTR_SIZE(size)); 15006dd4ee7cSKalpak Shah memcpy(b_entry_name, entry->e_name, entry->e_name_len); 15016dd4ee7cSKalpak Shah b_entry_name[entry->e_name_len] = '\0'; 15026dd4ee7cSKalpak Shah i.name = b_entry_name; 15036dd4ee7cSKalpak Shah 15046dd4ee7cSKalpak Shah error = ext4_get_inode_loc(inode, &is->iloc); 15056dd4ee7cSKalpak Shah if (error) 15066dd4ee7cSKalpak Shah goto cleanup; 15076dd4ee7cSKalpak Shah 15086dd4ee7cSKalpak Shah error = ext4_xattr_ibody_find(inode, &i, is); 15096dd4ee7cSKalpak Shah if (error) 15106dd4ee7cSKalpak Shah goto cleanup; 15116dd4ee7cSKalpak Shah 15126dd4ee7cSKalpak Shah /* Remove the chosen entry from the inode */ 15136dd4ee7cSKalpak Shah error = ext4_xattr_ibody_set(handle, inode, &i, is); 15149aaab058SRoel Kluin if (error) 15159aaab058SRoel Kluin goto cleanup; 15166dd4ee7cSKalpak Shah 15176dd4ee7cSKalpak Shah entry = IFIRST(header); 15186dd4ee7cSKalpak Shah if (entry_size + EXT4_XATTR_SIZE(size) >= new_extra_isize) 15196dd4ee7cSKalpak Shah shift_bytes = new_extra_isize; 15206dd4ee7cSKalpak Shah else 15216dd4ee7cSKalpak Shah shift_bytes = entry_size + size; 15226dd4ee7cSKalpak Shah /* Adjust the offsets and shift the remaining entries ahead */ 15236dd4ee7cSKalpak Shah ext4_xattr_shift_entries(entry, EXT4_I(inode)->i_extra_isize - 15246dd4ee7cSKalpak Shah shift_bytes, (void *)raw_inode + 15256dd4ee7cSKalpak Shah EXT4_GOOD_OLD_INODE_SIZE + extra_isize + shift_bytes, 15266dd4ee7cSKalpak Shah (void *)header, total_ino - entry_size, 15276dd4ee7cSKalpak Shah inode->i_sb->s_blocksize); 15286dd4ee7cSKalpak Shah 15296dd4ee7cSKalpak Shah extra_isize += shift_bytes; 15306dd4ee7cSKalpak Shah new_extra_isize -= shift_bytes; 15316dd4ee7cSKalpak Shah EXT4_I(inode)->i_extra_isize = extra_isize; 15326dd4ee7cSKalpak Shah 15336dd4ee7cSKalpak Shah i.name = b_entry_name; 15346dd4ee7cSKalpak Shah i.value = buffer; 1535ac39849dSAneesh Kumar K.V i.value_len = size; 15366dd4ee7cSKalpak Shah error = ext4_xattr_block_find(inode, &i, bs); 15376dd4ee7cSKalpak Shah if (error) 15386dd4ee7cSKalpak Shah goto cleanup; 15396dd4ee7cSKalpak Shah 15406dd4ee7cSKalpak Shah /* Add entry which was removed from the inode into the block */ 15416dd4ee7cSKalpak Shah error = ext4_xattr_block_set(handle, inode, &i, bs); 15426dd4ee7cSKalpak Shah if (error) 15436dd4ee7cSKalpak Shah goto cleanup; 15446dd4ee7cSKalpak Shah kfree(b_entry_name); 15456dd4ee7cSKalpak Shah kfree(buffer); 1546d3533d72SJulia Lawall b_entry_name = NULL; 1547d3533d72SJulia Lawall buffer = NULL; 15486dd4ee7cSKalpak Shah brelse(is->iloc.bh); 15496dd4ee7cSKalpak Shah kfree(is); 15506dd4ee7cSKalpak Shah kfree(bs); 15516dd4ee7cSKalpak Shah } 15526dd4ee7cSKalpak Shah brelse(bh); 15536dd4ee7cSKalpak Shah up_write(&EXT4_I(inode)->xattr_sem); 15546dd4ee7cSKalpak Shah return 0; 15556dd4ee7cSKalpak Shah 15566dd4ee7cSKalpak Shah cleanup: 15576dd4ee7cSKalpak Shah kfree(b_entry_name); 15586dd4ee7cSKalpak Shah kfree(buffer); 15596dd4ee7cSKalpak Shah if (is) 15606dd4ee7cSKalpak Shah brelse(is->iloc.bh); 15616dd4ee7cSKalpak Shah kfree(is); 15626dd4ee7cSKalpak Shah kfree(bs); 15636dd4ee7cSKalpak Shah brelse(bh); 15646dd4ee7cSKalpak Shah up_write(&EXT4_I(inode)->xattr_sem); 15656dd4ee7cSKalpak Shah return error; 15666dd4ee7cSKalpak Shah } 15676dd4ee7cSKalpak Shah 15686dd4ee7cSKalpak Shah 15696dd4ee7cSKalpak Shah 15706dd4ee7cSKalpak Shah /* 1571617ba13bSMingming Cao * ext4_xattr_delete_inode() 1572ac27a0ecSDave Kleikamp * 1573ac27a0ecSDave Kleikamp * Free extended attribute resources associated with this inode. This 1574ac27a0ecSDave Kleikamp * is called immediately before an inode is freed. We have exclusive 1575ac27a0ecSDave Kleikamp * access to the inode. 1576ac27a0ecSDave Kleikamp */ 1577ac27a0ecSDave Kleikamp void 1578617ba13bSMingming Cao ext4_xattr_delete_inode(handle_t *handle, struct inode *inode) 1579ac27a0ecSDave Kleikamp { 1580ac27a0ecSDave Kleikamp struct buffer_head *bh = NULL; 1581ac27a0ecSDave Kleikamp 1582617ba13bSMingming Cao if (!EXT4_I(inode)->i_file_acl) 1583ac27a0ecSDave Kleikamp goto cleanup; 1584617ba13bSMingming Cao bh = sb_bread(inode->i_sb, EXT4_I(inode)->i_file_acl); 1585ac27a0ecSDave Kleikamp if (!bh) { 158624676da4STheodore Ts'o EXT4_ERROR_INODE(inode, "block %llu read error", 158724676da4STheodore Ts'o EXT4_I(inode)->i_file_acl); 1588ac27a0ecSDave Kleikamp goto cleanup; 1589ac27a0ecSDave Kleikamp } 1590617ba13bSMingming Cao if (BHDR(bh)->h_magic != cpu_to_le32(EXT4_XATTR_MAGIC) || 1591ac27a0ecSDave Kleikamp BHDR(bh)->h_blocks != cpu_to_le32(1)) { 159224676da4STheodore Ts'o EXT4_ERROR_INODE(inode, "bad block %llu", 159324676da4STheodore Ts'o EXT4_I(inode)->i_file_acl); 1594ac27a0ecSDave Kleikamp goto cleanup; 1595ac27a0ecSDave Kleikamp } 1596617ba13bSMingming Cao ext4_xattr_release_block(handle, inode, bh); 1597617ba13bSMingming Cao EXT4_I(inode)->i_file_acl = 0; 1598ac27a0ecSDave Kleikamp 1599ac27a0ecSDave Kleikamp cleanup: 1600ac27a0ecSDave Kleikamp brelse(bh); 1601ac27a0ecSDave Kleikamp } 1602ac27a0ecSDave Kleikamp 1603ac27a0ecSDave Kleikamp /* 1604617ba13bSMingming Cao * ext4_xattr_cache_insert() 1605ac27a0ecSDave Kleikamp * 1606ac27a0ecSDave Kleikamp * Create a new entry in the extended attribute cache, and insert 1607ac27a0ecSDave Kleikamp * it unless such an entry is already in the cache. 1608ac27a0ecSDave Kleikamp * 1609ac27a0ecSDave Kleikamp * Returns 0, or a negative error number on failure. 1610ac27a0ecSDave Kleikamp */ 1611ac27a0ecSDave Kleikamp static void 16127a2508e1SJan Kara ext4_xattr_cache_insert(struct mb_cache *ext4_mb_cache, struct buffer_head *bh) 1613ac27a0ecSDave Kleikamp { 16146048c64bSAndreas Gruenbacher struct ext4_xattr_header *header = BHDR(bh); 16156048c64bSAndreas Gruenbacher __u32 hash = le32_to_cpu(header->h_hash); 16166048c64bSAndreas Gruenbacher int reusable = le32_to_cpu(header->h_refcount) < 16176048c64bSAndreas Gruenbacher EXT4_XATTR_REFCOUNT_MAX; 1618ac27a0ecSDave Kleikamp int error; 1619ac27a0ecSDave Kleikamp 16207a2508e1SJan Kara error = mb_cache_entry_create(ext4_mb_cache, GFP_NOFS, hash, 16216048c64bSAndreas Gruenbacher bh->b_blocknr, reusable); 1622ac27a0ecSDave Kleikamp if (error) { 162382939d79SJan Kara if (error == -EBUSY) 1624ac27a0ecSDave Kleikamp ea_bdebug(bh, "already in cache"); 162582939d79SJan Kara } else 1626ac27a0ecSDave Kleikamp ea_bdebug(bh, "inserting [%x]", (int)hash); 1627ac27a0ecSDave Kleikamp } 1628ac27a0ecSDave Kleikamp 1629ac27a0ecSDave Kleikamp /* 1630617ba13bSMingming Cao * ext4_xattr_cmp() 1631ac27a0ecSDave Kleikamp * 1632ac27a0ecSDave Kleikamp * Compare two extended attribute blocks for equality. 1633ac27a0ecSDave Kleikamp * 1634ac27a0ecSDave Kleikamp * Returns 0 if the blocks are equal, 1 if they differ, and 1635ac27a0ecSDave Kleikamp * a negative error number on errors. 1636ac27a0ecSDave Kleikamp */ 1637ac27a0ecSDave Kleikamp static int 1638617ba13bSMingming Cao ext4_xattr_cmp(struct ext4_xattr_header *header1, 1639617ba13bSMingming Cao struct ext4_xattr_header *header2) 1640ac27a0ecSDave Kleikamp { 1641617ba13bSMingming Cao struct ext4_xattr_entry *entry1, *entry2; 1642ac27a0ecSDave Kleikamp 1643ac27a0ecSDave Kleikamp entry1 = ENTRY(header1+1); 1644ac27a0ecSDave Kleikamp entry2 = ENTRY(header2+1); 1645ac27a0ecSDave Kleikamp while (!IS_LAST_ENTRY(entry1)) { 1646ac27a0ecSDave Kleikamp if (IS_LAST_ENTRY(entry2)) 1647ac27a0ecSDave Kleikamp return 1; 1648ac27a0ecSDave Kleikamp if (entry1->e_hash != entry2->e_hash || 1649ac27a0ecSDave Kleikamp entry1->e_name_index != entry2->e_name_index || 1650ac27a0ecSDave Kleikamp entry1->e_name_len != entry2->e_name_len || 1651ac27a0ecSDave Kleikamp entry1->e_value_size != entry2->e_value_size || 1652ac27a0ecSDave Kleikamp memcmp(entry1->e_name, entry2->e_name, entry1->e_name_len)) 1653ac27a0ecSDave Kleikamp return 1; 1654ac27a0ecSDave Kleikamp if (entry1->e_value_block != 0 || entry2->e_value_block != 0) 16556a797d27SDarrick J. Wong return -EFSCORRUPTED; 1656ac27a0ecSDave Kleikamp if (memcmp((char *)header1 + le16_to_cpu(entry1->e_value_offs), 1657ac27a0ecSDave Kleikamp (char *)header2 + le16_to_cpu(entry2->e_value_offs), 1658ac27a0ecSDave Kleikamp le32_to_cpu(entry1->e_value_size))) 1659ac27a0ecSDave Kleikamp return 1; 1660ac27a0ecSDave Kleikamp 1661617ba13bSMingming Cao entry1 = EXT4_XATTR_NEXT(entry1); 1662617ba13bSMingming Cao entry2 = EXT4_XATTR_NEXT(entry2); 1663ac27a0ecSDave Kleikamp } 1664ac27a0ecSDave Kleikamp if (!IS_LAST_ENTRY(entry2)) 1665ac27a0ecSDave Kleikamp return 1; 1666ac27a0ecSDave Kleikamp return 0; 1667ac27a0ecSDave Kleikamp } 1668ac27a0ecSDave Kleikamp 1669ac27a0ecSDave Kleikamp /* 1670617ba13bSMingming Cao * ext4_xattr_cache_find() 1671ac27a0ecSDave Kleikamp * 1672ac27a0ecSDave Kleikamp * Find an identical extended attribute block. 1673ac27a0ecSDave Kleikamp * 1674ac27a0ecSDave Kleikamp * Returns a pointer to the block found, or NULL if such a block was 1675ac27a0ecSDave Kleikamp * not found or an error occurred. 1676ac27a0ecSDave Kleikamp */ 1677ac27a0ecSDave Kleikamp static struct buffer_head * 1678617ba13bSMingming Cao ext4_xattr_cache_find(struct inode *inode, struct ext4_xattr_header *header, 16797a2508e1SJan Kara struct mb_cache_entry **pce) 1680ac27a0ecSDave Kleikamp { 1681ac27a0ecSDave Kleikamp __u32 hash = le32_to_cpu(header->h_hash); 16827a2508e1SJan Kara struct mb_cache_entry *ce; 16837a2508e1SJan Kara struct mb_cache *ext4_mb_cache = EXT4_GET_MB_CACHE(inode); 1684ac27a0ecSDave Kleikamp 1685ac27a0ecSDave Kleikamp if (!header->h_hash) 1686ac27a0ecSDave Kleikamp return NULL; /* never share */ 1687ac27a0ecSDave Kleikamp ea_idebug(inode, "looking for cached blocks [%x]", (int)hash); 16887a2508e1SJan Kara ce = mb_cache_entry_find_first(ext4_mb_cache, hash); 1689ac27a0ecSDave Kleikamp while (ce) { 1690ac27a0ecSDave Kleikamp struct buffer_head *bh; 1691ac27a0ecSDave Kleikamp 1692ac27a0ecSDave Kleikamp bh = sb_bread(inode->i_sb, ce->e_block); 1693ac27a0ecSDave Kleikamp if (!bh) { 169424676da4STheodore Ts'o EXT4_ERROR_INODE(inode, "block %lu read error", 169524676da4STheodore Ts'o (unsigned long) ce->e_block); 1696617ba13bSMingming Cao } else if (ext4_xattr_cmp(header, BHDR(bh)) == 0) { 1697ac27a0ecSDave Kleikamp *pce = ce; 1698ac27a0ecSDave Kleikamp return bh; 1699ac27a0ecSDave Kleikamp } 1700ac27a0ecSDave Kleikamp brelse(bh); 17017a2508e1SJan Kara ce = mb_cache_entry_find_next(ext4_mb_cache, ce); 1702ac27a0ecSDave Kleikamp } 1703ac27a0ecSDave Kleikamp return NULL; 1704ac27a0ecSDave Kleikamp } 1705ac27a0ecSDave Kleikamp 1706ac27a0ecSDave Kleikamp #define NAME_HASH_SHIFT 5 1707ac27a0ecSDave Kleikamp #define VALUE_HASH_SHIFT 16 1708ac27a0ecSDave Kleikamp 1709ac27a0ecSDave Kleikamp /* 1710617ba13bSMingming Cao * ext4_xattr_hash_entry() 1711ac27a0ecSDave Kleikamp * 1712ac27a0ecSDave Kleikamp * Compute the hash of an extended attribute. 1713ac27a0ecSDave Kleikamp */ 1714617ba13bSMingming Cao static inline void ext4_xattr_hash_entry(struct ext4_xattr_header *header, 1715617ba13bSMingming Cao struct ext4_xattr_entry *entry) 1716ac27a0ecSDave Kleikamp { 1717ac27a0ecSDave Kleikamp __u32 hash = 0; 1718ac27a0ecSDave Kleikamp char *name = entry->e_name; 1719ac27a0ecSDave Kleikamp int n; 1720ac27a0ecSDave Kleikamp 1721ac27a0ecSDave Kleikamp for (n = 0; n < entry->e_name_len; n++) { 1722ac27a0ecSDave Kleikamp hash = (hash << NAME_HASH_SHIFT) ^ 1723ac27a0ecSDave Kleikamp (hash >> (8*sizeof(hash) - NAME_HASH_SHIFT)) ^ 1724ac27a0ecSDave Kleikamp *name++; 1725ac27a0ecSDave Kleikamp } 1726ac27a0ecSDave Kleikamp 1727ac27a0ecSDave Kleikamp if (entry->e_value_block == 0 && entry->e_value_size != 0) { 1728ac27a0ecSDave Kleikamp __le32 *value = (__le32 *)((char *)header + 1729ac27a0ecSDave Kleikamp le16_to_cpu(entry->e_value_offs)); 1730ac27a0ecSDave Kleikamp for (n = (le32_to_cpu(entry->e_value_size) + 1731617ba13bSMingming Cao EXT4_XATTR_ROUND) >> EXT4_XATTR_PAD_BITS; n; n--) { 1732ac27a0ecSDave Kleikamp hash = (hash << VALUE_HASH_SHIFT) ^ 1733ac27a0ecSDave Kleikamp (hash >> (8*sizeof(hash) - VALUE_HASH_SHIFT)) ^ 1734ac27a0ecSDave Kleikamp le32_to_cpu(*value++); 1735ac27a0ecSDave Kleikamp } 1736ac27a0ecSDave Kleikamp } 1737ac27a0ecSDave Kleikamp entry->e_hash = cpu_to_le32(hash); 1738ac27a0ecSDave Kleikamp } 1739ac27a0ecSDave Kleikamp 1740ac27a0ecSDave Kleikamp #undef NAME_HASH_SHIFT 1741ac27a0ecSDave Kleikamp #undef VALUE_HASH_SHIFT 1742ac27a0ecSDave Kleikamp 1743ac27a0ecSDave Kleikamp #define BLOCK_HASH_SHIFT 16 1744ac27a0ecSDave Kleikamp 1745ac27a0ecSDave Kleikamp /* 1746617ba13bSMingming Cao * ext4_xattr_rehash() 1747ac27a0ecSDave Kleikamp * 1748ac27a0ecSDave Kleikamp * Re-compute the extended attribute hash value after an entry has changed. 1749ac27a0ecSDave Kleikamp */ 1750617ba13bSMingming Cao static void ext4_xattr_rehash(struct ext4_xattr_header *header, 1751617ba13bSMingming Cao struct ext4_xattr_entry *entry) 1752ac27a0ecSDave Kleikamp { 1753617ba13bSMingming Cao struct ext4_xattr_entry *here; 1754ac27a0ecSDave Kleikamp __u32 hash = 0; 1755ac27a0ecSDave Kleikamp 1756617ba13bSMingming Cao ext4_xattr_hash_entry(header, entry); 1757ac27a0ecSDave Kleikamp here = ENTRY(header+1); 1758ac27a0ecSDave Kleikamp while (!IS_LAST_ENTRY(here)) { 1759ac27a0ecSDave Kleikamp if (!here->e_hash) { 1760ac27a0ecSDave Kleikamp /* Block is not shared if an entry's hash value == 0 */ 1761ac27a0ecSDave Kleikamp hash = 0; 1762ac27a0ecSDave Kleikamp break; 1763ac27a0ecSDave Kleikamp } 1764ac27a0ecSDave Kleikamp hash = (hash << BLOCK_HASH_SHIFT) ^ 1765ac27a0ecSDave Kleikamp (hash >> (8*sizeof(hash) - BLOCK_HASH_SHIFT)) ^ 1766ac27a0ecSDave Kleikamp le32_to_cpu(here->e_hash); 1767617ba13bSMingming Cao here = EXT4_XATTR_NEXT(here); 1768ac27a0ecSDave Kleikamp } 1769ac27a0ecSDave Kleikamp header->h_hash = cpu_to_le32(hash); 1770ac27a0ecSDave Kleikamp } 1771ac27a0ecSDave Kleikamp 1772ac27a0ecSDave Kleikamp #undef BLOCK_HASH_SHIFT 1773ac27a0ecSDave Kleikamp 17749c191f70ST Makphaibulchoke #define HASH_BUCKET_BITS 10 17759c191f70ST Makphaibulchoke 17767a2508e1SJan Kara struct mb_cache * 177782939d79SJan Kara ext4_xattr_create_cache(void) 1778ac27a0ecSDave Kleikamp { 17797a2508e1SJan Kara return mb_cache_create(HASH_BUCKET_BITS); 1780ac27a0ecSDave Kleikamp } 1781ac27a0ecSDave Kleikamp 17827a2508e1SJan Kara void ext4_xattr_destroy_cache(struct mb_cache *cache) 1783ac27a0ecSDave Kleikamp { 17849c191f70ST Makphaibulchoke if (cache) 17857a2508e1SJan Kara mb_cache_destroy(cache); 1786ac27a0ecSDave Kleikamp } 17879c191f70ST Makphaibulchoke 1788