11da177e4SLinus Torvalds /* dir.c: AFS filesystem directory handling 21da177e4SLinus Torvalds * 31da177e4SLinus Torvalds * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved. 41da177e4SLinus Torvalds * Written by David Howells (dhowells@redhat.com) 51da177e4SLinus Torvalds * 61da177e4SLinus Torvalds * This program is free software; you can redistribute it and/or 71da177e4SLinus Torvalds * modify it under the terms of the GNU General Public License 81da177e4SLinus Torvalds * as published by the Free Software Foundation; either version 91da177e4SLinus Torvalds * 2 of the License, or (at your option) any later version. 101da177e4SLinus Torvalds */ 111da177e4SLinus Torvalds 121da177e4SLinus Torvalds #include <linux/kernel.h> 131da177e4SLinus Torvalds #include <linux/module.h> 141da177e4SLinus Torvalds #include <linux/init.h> 151da177e4SLinus Torvalds #include <linux/slab.h> 161da177e4SLinus Torvalds #include <linux/fs.h> 171da177e4SLinus Torvalds #include <linux/pagemap.h> 181da177e4SLinus Torvalds #include "internal.h" 191da177e4SLinus Torvalds 201da177e4SLinus Torvalds static struct dentry *afs_dir_lookup(struct inode *dir, struct dentry *dentry, 211da177e4SLinus Torvalds struct nameidata *nd); 221da177e4SLinus Torvalds static int afs_dir_open(struct inode *inode, struct file *file); 231da177e4SLinus Torvalds static int afs_dir_readdir(struct file *file, void *dirent, filldir_t filldir); 241da177e4SLinus Torvalds static int afs_d_revalidate(struct dentry *dentry, struct nameidata *nd); 251da177e4SLinus Torvalds static int afs_d_delete(struct dentry *dentry); 261da177e4SLinus Torvalds static int afs_dir_lookup_filldir(void *_cookie, const char *name, int nlen, 27afefdbb2SDavid Howells loff_t fpos, u64 ino, unsigned dtype); 281da177e4SLinus Torvalds 294b6f5d20SArjan van de Ven const struct file_operations afs_dir_file_operations = { 301da177e4SLinus Torvalds .open = afs_dir_open, 311da177e4SLinus Torvalds .readdir = afs_dir_readdir, 321da177e4SLinus Torvalds }; 331da177e4SLinus Torvalds 34754661f1SArjan van de Ven const struct inode_operations afs_dir_inode_operations = { 351da177e4SLinus Torvalds .lookup = afs_dir_lookup, 361da177e4SLinus Torvalds .getattr = afs_inode_getattr, 371da177e4SLinus Torvalds #if 0 /* TODO */ 381da177e4SLinus Torvalds .create = afs_dir_create, 391da177e4SLinus Torvalds .link = afs_dir_link, 401da177e4SLinus Torvalds .unlink = afs_dir_unlink, 411da177e4SLinus Torvalds .symlink = afs_dir_symlink, 421da177e4SLinus Torvalds .mkdir = afs_dir_mkdir, 431da177e4SLinus Torvalds .rmdir = afs_dir_rmdir, 441da177e4SLinus Torvalds .mknod = afs_dir_mknod, 451da177e4SLinus Torvalds .rename = afs_dir_rename, 461da177e4SLinus Torvalds #endif 471da177e4SLinus Torvalds }; 481da177e4SLinus Torvalds 491da177e4SLinus Torvalds static struct dentry_operations afs_fs_dentry_operations = { 501da177e4SLinus Torvalds .d_revalidate = afs_d_revalidate, 511da177e4SLinus Torvalds .d_delete = afs_d_delete, 521da177e4SLinus Torvalds }; 531da177e4SLinus Torvalds 541da177e4SLinus Torvalds #define AFS_DIR_HASHTBL_SIZE 128 551da177e4SLinus Torvalds #define AFS_DIR_DIRENT_SIZE 32 561da177e4SLinus Torvalds #define AFS_DIRENT_PER_BLOCK 64 571da177e4SLinus Torvalds 581da177e4SLinus Torvalds union afs_dirent { 591da177e4SLinus Torvalds struct { 601da177e4SLinus Torvalds uint8_t valid; 611da177e4SLinus Torvalds uint8_t unused[1]; 621da177e4SLinus Torvalds __be16 hash_next; 631da177e4SLinus Torvalds __be32 vnode; 641da177e4SLinus Torvalds __be32 unique; 651da177e4SLinus Torvalds uint8_t name[16]; 661da177e4SLinus Torvalds uint8_t overflow[4]; /* if any char of the name (inc 671da177e4SLinus Torvalds * NUL) reaches here, consume 681da177e4SLinus Torvalds * the next dirent too */ 691da177e4SLinus Torvalds } u; 701da177e4SLinus Torvalds uint8_t extended_name[32]; 711da177e4SLinus Torvalds }; 721da177e4SLinus Torvalds 731da177e4SLinus Torvalds /* AFS directory page header (one at the beginning of every 2048-byte chunk) */ 741da177e4SLinus Torvalds struct afs_dir_pagehdr { 751da177e4SLinus Torvalds __be16 npages; 761da177e4SLinus Torvalds __be16 magic; 771da177e4SLinus Torvalds #define AFS_DIR_MAGIC htons(1234) 781da177e4SLinus Torvalds uint8_t nentries; 791da177e4SLinus Torvalds uint8_t bitmap[8]; 801da177e4SLinus Torvalds uint8_t pad[19]; 811da177e4SLinus Torvalds }; 821da177e4SLinus Torvalds 831da177e4SLinus Torvalds /* directory block layout */ 841da177e4SLinus Torvalds union afs_dir_block { 851da177e4SLinus Torvalds 861da177e4SLinus Torvalds struct afs_dir_pagehdr pagehdr; 871da177e4SLinus Torvalds 881da177e4SLinus Torvalds struct { 891da177e4SLinus Torvalds struct afs_dir_pagehdr pagehdr; 901da177e4SLinus Torvalds uint8_t alloc_ctrs[128]; 911da177e4SLinus Torvalds /* dir hash table */ 921da177e4SLinus Torvalds uint16_t hashtable[AFS_DIR_HASHTBL_SIZE]; 931da177e4SLinus Torvalds } hdr; 941da177e4SLinus Torvalds 951da177e4SLinus Torvalds union afs_dirent dirents[AFS_DIRENT_PER_BLOCK]; 961da177e4SLinus Torvalds }; 971da177e4SLinus Torvalds 981da177e4SLinus Torvalds /* layout on a linux VM page */ 991da177e4SLinus Torvalds struct afs_dir_page { 1001da177e4SLinus Torvalds union afs_dir_block blocks[PAGE_SIZE / sizeof(union afs_dir_block)]; 1011da177e4SLinus Torvalds }; 1021da177e4SLinus Torvalds 1031da177e4SLinus Torvalds struct afs_dir_lookup_cookie { 1041da177e4SLinus Torvalds struct afs_fid fid; 1051da177e4SLinus Torvalds const char *name; 1061da177e4SLinus Torvalds size_t nlen; 1071da177e4SLinus Torvalds int found; 1081da177e4SLinus Torvalds }; 1091da177e4SLinus Torvalds 1101da177e4SLinus Torvalds /* 1111da177e4SLinus Torvalds * check that a directory page is valid 1121da177e4SLinus Torvalds */ 1131da177e4SLinus Torvalds static inline void afs_dir_check_page(struct inode *dir, struct page *page) 1141da177e4SLinus Torvalds { 1151da177e4SLinus Torvalds struct afs_dir_page *dbuf; 1161da177e4SLinus Torvalds loff_t latter; 1171da177e4SLinus Torvalds int tmp, qty; 1181da177e4SLinus Torvalds 1191da177e4SLinus Torvalds #if 0 1201da177e4SLinus Torvalds /* check the page count */ 1211da177e4SLinus Torvalds qty = desc.size / sizeof(dbuf->blocks[0]); 1221da177e4SLinus Torvalds if (qty == 0) 1231da177e4SLinus Torvalds goto error; 1241da177e4SLinus Torvalds 1251da177e4SLinus Torvalds if (page->index == 0 && qty != ntohs(dbuf->blocks[0].pagehdr.npages)) { 1261da177e4SLinus Torvalds printk("kAFS: %s(%lu): wrong number of dir blocks %d!=%hu\n", 12708e0e7c8SDavid Howells __FUNCTION__, dir->i_ino, qty, 12808e0e7c8SDavid Howells ntohs(dbuf->blocks[0].pagehdr.npages)); 1291da177e4SLinus Torvalds goto error; 1301da177e4SLinus Torvalds } 1311da177e4SLinus Torvalds #endif 1321da177e4SLinus Torvalds 1331da177e4SLinus Torvalds /* determine how many magic numbers there should be in this page */ 13454b21a79SAndrew Morton latter = dir->i_size - page_offset(page); 1351da177e4SLinus Torvalds if (latter >= PAGE_SIZE) 1361da177e4SLinus Torvalds qty = PAGE_SIZE; 1371da177e4SLinus Torvalds else 1381da177e4SLinus Torvalds qty = latter; 1391da177e4SLinus Torvalds qty /= sizeof(union afs_dir_block); 1401da177e4SLinus Torvalds 1411da177e4SLinus Torvalds /* check them */ 1421da177e4SLinus Torvalds dbuf = page_address(page); 1431da177e4SLinus Torvalds for (tmp = 0; tmp < qty; tmp++) { 1441da177e4SLinus Torvalds if (dbuf->blocks[tmp].pagehdr.magic != AFS_DIR_MAGIC) { 1451da177e4SLinus Torvalds printk("kAFS: %s(%lu): bad magic %d/%d is %04hx\n", 1461da177e4SLinus Torvalds __FUNCTION__, dir->i_ino, tmp, qty, 1471da177e4SLinus Torvalds ntohs(dbuf->blocks[tmp].pagehdr.magic)); 1481da177e4SLinus Torvalds goto error; 1491da177e4SLinus Torvalds } 1501da177e4SLinus Torvalds } 1511da177e4SLinus Torvalds 1521da177e4SLinus Torvalds SetPageChecked(page); 1531da177e4SLinus Torvalds return; 1541da177e4SLinus Torvalds 1551da177e4SLinus Torvalds error: 1561da177e4SLinus Torvalds SetPageChecked(page); 1571da177e4SLinus Torvalds SetPageError(page); 158ec26815aSDavid Howells } 1591da177e4SLinus Torvalds 1601da177e4SLinus Torvalds /* 1611da177e4SLinus Torvalds * discard a page cached in the pagecache 1621da177e4SLinus Torvalds */ 1631da177e4SLinus Torvalds static inline void afs_dir_put_page(struct page *page) 1641da177e4SLinus Torvalds { 1651da177e4SLinus Torvalds kunmap(page); 1661da177e4SLinus Torvalds page_cache_release(page); 167ec26815aSDavid Howells } 1681da177e4SLinus Torvalds 1691da177e4SLinus Torvalds /* 1701da177e4SLinus Torvalds * get a page into the pagecache 1711da177e4SLinus Torvalds */ 1721da177e4SLinus Torvalds static struct page *afs_dir_get_page(struct inode *dir, unsigned long index) 1731da177e4SLinus Torvalds { 1741da177e4SLinus Torvalds struct page *page; 1751da177e4SLinus Torvalds 1761da177e4SLinus Torvalds _enter("{%lu},%lu", dir->i_ino, index); 1771da177e4SLinus Torvalds 178090d2b18SPekka Enberg page = read_mapping_page(dir->i_mapping, index, NULL); 1791da177e4SLinus Torvalds if (!IS_ERR(page)) { 1801da177e4SLinus Torvalds wait_on_page_locked(page); 1811da177e4SLinus Torvalds kmap(page); 1821da177e4SLinus Torvalds if (!PageUptodate(page)) 1831da177e4SLinus Torvalds goto fail; 1841da177e4SLinus Torvalds if (!PageChecked(page)) 1851da177e4SLinus Torvalds afs_dir_check_page(dir, page); 1861da177e4SLinus Torvalds if (PageError(page)) 1871da177e4SLinus Torvalds goto fail; 1881da177e4SLinus Torvalds } 1891da177e4SLinus Torvalds return page; 1901da177e4SLinus Torvalds 1911da177e4SLinus Torvalds fail: 1921da177e4SLinus Torvalds afs_dir_put_page(page); 19308e0e7c8SDavid Howells _leave(" = -EIO"); 1941da177e4SLinus Torvalds return ERR_PTR(-EIO); 195ec26815aSDavid Howells } 1961da177e4SLinus Torvalds 1971da177e4SLinus Torvalds /* 1981da177e4SLinus Torvalds * open an AFS directory file 1991da177e4SLinus Torvalds */ 2001da177e4SLinus Torvalds static int afs_dir_open(struct inode *inode, struct file *file) 2011da177e4SLinus Torvalds { 2021da177e4SLinus Torvalds _enter("{%lu}", inode->i_ino); 2031da177e4SLinus Torvalds 2042ecd05aeSAlexey Dobriyan BUILD_BUG_ON(sizeof(union afs_dir_block) != 2048); 2052ecd05aeSAlexey Dobriyan BUILD_BUG_ON(sizeof(union afs_dirent) != 32); 2061da177e4SLinus Torvalds 20708e0e7c8SDavid Howells if (test_bit(AFS_VNODE_DELETED, &AFS_FS_I(inode)->flags)) 2081da177e4SLinus Torvalds return -ENOENT; 2091da177e4SLinus Torvalds 2101da177e4SLinus Torvalds _leave(" = 0"); 2111da177e4SLinus Torvalds return 0; 212ec26815aSDavid Howells } 2131da177e4SLinus Torvalds 2141da177e4SLinus Torvalds /* 2151da177e4SLinus Torvalds * deal with one block in an AFS directory 2161da177e4SLinus Torvalds */ 2171da177e4SLinus Torvalds static int afs_dir_iterate_block(unsigned *fpos, 2181da177e4SLinus Torvalds union afs_dir_block *block, 2191da177e4SLinus Torvalds unsigned blkoff, 2201da177e4SLinus Torvalds void *cookie, 2211da177e4SLinus Torvalds filldir_t filldir) 2221da177e4SLinus Torvalds { 2231da177e4SLinus Torvalds union afs_dirent *dire; 2241da177e4SLinus Torvalds unsigned offset, next, curr; 2251da177e4SLinus Torvalds size_t nlen; 2261da177e4SLinus Torvalds int tmp, ret; 2271da177e4SLinus Torvalds 2281da177e4SLinus Torvalds _enter("%u,%x,%p,,",*fpos,blkoff,block); 2291da177e4SLinus Torvalds 2301da177e4SLinus Torvalds curr = (*fpos - blkoff) / sizeof(union afs_dirent); 2311da177e4SLinus Torvalds 2321da177e4SLinus Torvalds /* walk through the block, an entry at a time */ 2331da177e4SLinus Torvalds for (offset = AFS_DIRENT_PER_BLOCK - block->pagehdr.nentries; 2341da177e4SLinus Torvalds offset < AFS_DIRENT_PER_BLOCK; 2351da177e4SLinus Torvalds offset = next 2361da177e4SLinus Torvalds ) { 2371da177e4SLinus Torvalds next = offset + 1; 2381da177e4SLinus Torvalds 2391da177e4SLinus Torvalds /* skip entries marked unused in the bitmap */ 2401da177e4SLinus Torvalds if (!(block->pagehdr.bitmap[offset / 8] & 2411da177e4SLinus Torvalds (1 << (offset % 8)))) { 24208e0e7c8SDavid Howells _debug("ENT[%Zu.%u]: unused", 2431da177e4SLinus Torvalds blkoff / sizeof(union afs_dir_block), offset); 2441da177e4SLinus Torvalds if (offset >= curr) 2451da177e4SLinus Torvalds *fpos = blkoff + 2461da177e4SLinus Torvalds next * sizeof(union afs_dirent); 2471da177e4SLinus Torvalds continue; 2481da177e4SLinus Torvalds } 2491da177e4SLinus Torvalds 2501da177e4SLinus Torvalds /* got a valid entry */ 2511da177e4SLinus Torvalds dire = &block->dirents[offset]; 2521da177e4SLinus Torvalds nlen = strnlen(dire->u.name, 2531da177e4SLinus Torvalds sizeof(*block) - 2541da177e4SLinus Torvalds offset * sizeof(union afs_dirent)); 2551da177e4SLinus Torvalds 25608e0e7c8SDavid Howells _debug("ENT[%Zu.%u]: %s %Zu \"%s\"", 2571da177e4SLinus Torvalds blkoff / sizeof(union afs_dir_block), offset, 2581da177e4SLinus Torvalds (offset < curr ? "skip" : "fill"), 2591da177e4SLinus Torvalds nlen, dire->u.name); 2601da177e4SLinus Torvalds 2611da177e4SLinus Torvalds /* work out where the next possible entry is */ 2621da177e4SLinus Torvalds for (tmp = nlen; tmp > 15; tmp -= sizeof(union afs_dirent)) { 2631da177e4SLinus Torvalds if (next >= AFS_DIRENT_PER_BLOCK) { 2641da177e4SLinus Torvalds _debug("ENT[%Zu.%u]:" 2651da177e4SLinus Torvalds " %u travelled beyond end dir block" 26608e0e7c8SDavid Howells " (len %u/%Zu)", 2671da177e4SLinus Torvalds blkoff / sizeof(union afs_dir_block), 2681da177e4SLinus Torvalds offset, next, tmp, nlen); 2691da177e4SLinus Torvalds return -EIO; 2701da177e4SLinus Torvalds } 2711da177e4SLinus Torvalds if (!(block->pagehdr.bitmap[next / 8] & 2721da177e4SLinus Torvalds (1 << (next % 8)))) { 2731da177e4SLinus Torvalds _debug("ENT[%Zu.%u]:" 27408e0e7c8SDavid Howells " %u unmarked extension (len %u/%Zu)", 2751da177e4SLinus Torvalds blkoff / sizeof(union afs_dir_block), 2761da177e4SLinus Torvalds offset, next, tmp, nlen); 2771da177e4SLinus Torvalds return -EIO; 2781da177e4SLinus Torvalds } 2791da177e4SLinus Torvalds 28008e0e7c8SDavid Howells _debug("ENT[%Zu.%u]: ext %u/%Zu", 2811da177e4SLinus Torvalds blkoff / sizeof(union afs_dir_block), 2821da177e4SLinus Torvalds next, tmp, nlen); 2831da177e4SLinus Torvalds next++; 2841da177e4SLinus Torvalds } 2851da177e4SLinus Torvalds 2861da177e4SLinus Torvalds /* skip if starts before the current position */ 2871da177e4SLinus Torvalds if (offset < curr) 2881da177e4SLinus Torvalds continue; 2891da177e4SLinus Torvalds 2901da177e4SLinus Torvalds /* found the next entry */ 2911da177e4SLinus Torvalds ret = filldir(cookie, 2921da177e4SLinus Torvalds dire->u.name, 2931da177e4SLinus Torvalds nlen, 2941da177e4SLinus Torvalds blkoff + offset * sizeof(union afs_dirent), 2951da177e4SLinus Torvalds ntohl(dire->u.vnode), 2961da177e4SLinus Torvalds filldir == afs_dir_lookup_filldir ? 2971da177e4SLinus Torvalds ntohl(dire->u.unique) : DT_UNKNOWN); 2981da177e4SLinus Torvalds if (ret < 0) { 2991da177e4SLinus Torvalds _leave(" = 0 [full]"); 3001da177e4SLinus Torvalds return 0; 3011da177e4SLinus Torvalds } 3021da177e4SLinus Torvalds 3031da177e4SLinus Torvalds *fpos = blkoff + next * sizeof(union afs_dirent); 3041da177e4SLinus Torvalds } 3051da177e4SLinus Torvalds 3061da177e4SLinus Torvalds _leave(" = 1 [more]"); 3071da177e4SLinus Torvalds return 1; 308ec26815aSDavid Howells } 3091da177e4SLinus Torvalds 3101da177e4SLinus Torvalds /* 31108e0e7c8SDavid Howells * iterate through the data blob that lists the contents of an AFS directory 3121da177e4SLinus Torvalds */ 3131da177e4SLinus Torvalds static int afs_dir_iterate(struct inode *dir, unsigned *fpos, void *cookie, 3141da177e4SLinus Torvalds filldir_t filldir) 3151da177e4SLinus Torvalds { 3161da177e4SLinus Torvalds union afs_dir_block *dblock; 3171da177e4SLinus Torvalds struct afs_dir_page *dbuf; 3181da177e4SLinus Torvalds struct page *page; 3191da177e4SLinus Torvalds unsigned blkoff, limit; 3201da177e4SLinus Torvalds int ret; 3211da177e4SLinus Torvalds 3221da177e4SLinus Torvalds _enter("{%lu},%u,,", dir->i_ino, *fpos); 3231da177e4SLinus Torvalds 32408e0e7c8SDavid Howells if (test_bit(AFS_VNODE_DELETED, &AFS_FS_I(dir)->flags)) { 3251da177e4SLinus Torvalds _leave(" = -ESTALE"); 3261da177e4SLinus Torvalds return -ESTALE; 3271da177e4SLinus Torvalds } 3281da177e4SLinus Torvalds 3291da177e4SLinus Torvalds /* round the file position up to the next entry boundary */ 3301da177e4SLinus Torvalds *fpos += sizeof(union afs_dirent) - 1; 3311da177e4SLinus Torvalds *fpos &= ~(sizeof(union afs_dirent) - 1); 3321da177e4SLinus Torvalds 3331da177e4SLinus Torvalds /* walk through the blocks in sequence */ 3341da177e4SLinus Torvalds ret = 0; 3351da177e4SLinus Torvalds while (*fpos < dir->i_size) { 3361da177e4SLinus Torvalds blkoff = *fpos & ~(sizeof(union afs_dir_block) - 1); 3371da177e4SLinus Torvalds 3381da177e4SLinus Torvalds /* fetch the appropriate page from the directory */ 3391da177e4SLinus Torvalds page = afs_dir_get_page(dir, blkoff / PAGE_SIZE); 3401da177e4SLinus Torvalds if (IS_ERR(page)) { 3411da177e4SLinus Torvalds ret = PTR_ERR(page); 3421da177e4SLinus Torvalds break; 3431da177e4SLinus Torvalds } 3441da177e4SLinus Torvalds 3451da177e4SLinus Torvalds limit = blkoff & ~(PAGE_SIZE - 1); 3461da177e4SLinus Torvalds 3471da177e4SLinus Torvalds dbuf = page_address(page); 3481da177e4SLinus Torvalds 3491da177e4SLinus Torvalds /* deal with the individual blocks stashed on this page */ 3501da177e4SLinus Torvalds do { 3511da177e4SLinus Torvalds dblock = &dbuf->blocks[(blkoff % PAGE_SIZE) / 3521da177e4SLinus Torvalds sizeof(union afs_dir_block)]; 3531da177e4SLinus Torvalds ret = afs_dir_iterate_block(fpos, dblock, blkoff, 3541da177e4SLinus Torvalds cookie, filldir); 3551da177e4SLinus Torvalds if (ret != 1) { 3561da177e4SLinus Torvalds afs_dir_put_page(page); 3571da177e4SLinus Torvalds goto out; 3581da177e4SLinus Torvalds } 3591da177e4SLinus Torvalds 3601da177e4SLinus Torvalds blkoff += sizeof(union afs_dir_block); 3611da177e4SLinus Torvalds 3621da177e4SLinus Torvalds } while (*fpos < dir->i_size && blkoff < limit); 3631da177e4SLinus Torvalds 3641da177e4SLinus Torvalds afs_dir_put_page(page); 3651da177e4SLinus Torvalds ret = 0; 3661da177e4SLinus Torvalds } 3671da177e4SLinus Torvalds 3681da177e4SLinus Torvalds out: 3691da177e4SLinus Torvalds _leave(" = %d", ret); 3701da177e4SLinus Torvalds return ret; 371ec26815aSDavid Howells } 3721da177e4SLinus Torvalds 3731da177e4SLinus Torvalds /* 3741da177e4SLinus Torvalds * read an AFS directory 3751da177e4SLinus Torvalds */ 3761da177e4SLinus Torvalds static int afs_dir_readdir(struct file *file, void *cookie, filldir_t filldir) 3771da177e4SLinus Torvalds { 3781da177e4SLinus Torvalds unsigned fpos; 3791da177e4SLinus Torvalds int ret; 3801da177e4SLinus Torvalds 38108e0e7c8SDavid Howells _enter("{%Ld,{%lu}}", 38208e0e7c8SDavid Howells file->f_pos, file->f_path.dentry->d_inode->i_ino); 3831da177e4SLinus Torvalds 3841da177e4SLinus Torvalds fpos = file->f_pos; 38508e0e7c8SDavid Howells ret = afs_dir_iterate(file->f_path.dentry->d_inode, &fpos, 38608e0e7c8SDavid Howells cookie, filldir); 3871da177e4SLinus Torvalds file->f_pos = fpos; 3881da177e4SLinus Torvalds 3891da177e4SLinus Torvalds _leave(" = %d", ret); 3901da177e4SLinus Torvalds return ret; 391ec26815aSDavid Howells } 3921da177e4SLinus Torvalds 3931da177e4SLinus Torvalds /* 3941da177e4SLinus Torvalds * search the directory for a name 3951da177e4SLinus Torvalds * - if afs_dir_iterate_block() spots this function, it'll pass the FID 3961da177e4SLinus Torvalds * uniquifier through dtype 3971da177e4SLinus Torvalds */ 3981da177e4SLinus Torvalds static int afs_dir_lookup_filldir(void *_cookie, const char *name, int nlen, 399afefdbb2SDavid Howells loff_t fpos, u64 ino, unsigned dtype) 4001da177e4SLinus Torvalds { 4011da177e4SLinus Torvalds struct afs_dir_lookup_cookie *cookie = _cookie; 4021da177e4SLinus Torvalds 40308e0e7c8SDavid Howells _enter("{%s,%Zu},%s,%u,,%llu,%u", 4041da177e4SLinus Torvalds cookie->name, cookie->nlen, name, nlen, ino, dtype); 4051da177e4SLinus Torvalds 40608e0e7c8SDavid Howells /* insanity checks first */ 40708e0e7c8SDavid Howells BUILD_BUG_ON(sizeof(union afs_dir_block) != 2048); 40808e0e7c8SDavid Howells BUILD_BUG_ON(sizeof(union afs_dirent) != 32); 40908e0e7c8SDavid Howells 4101da177e4SLinus Torvalds if (cookie->nlen != nlen || memcmp(cookie->name, name, nlen) != 0) { 4111da177e4SLinus Torvalds _leave(" = 0 [no]"); 4121da177e4SLinus Torvalds return 0; 4131da177e4SLinus Torvalds } 4141da177e4SLinus Torvalds 4151da177e4SLinus Torvalds cookie->fid.vnode = ino; 4161da177e4SLinus Torvalds cookie->fid.unique = dtype; 4171da177e4SLinus Torvalds cookie->found = 1; 4181da177e4SLinus Torvalds 4191da177e4SLinus Torvalds _leave(" = -1 [found]"); 4201da177e4SLinus Torvalds return -1; 421ec26815aSDavid Howells } 4221da177e4SLinus Torvalds 4231da177e4SLinus Torvalds /* 42408e0e7c8SDavid Howells * do a lookup in a directory 4251da177e4SLinus Torvalds */ 42608e0e7c8SDavid Howells static int afs_do_lookup(struct inode *dir, struct dentry *dentry, 42708e0e7c8SDavid Howells struct afs_fid *fid) 4281da177e4SLinus Torvalds { 4291da177e4SLinus Torvalds struct afs_dir_lookup_cookie cookie; 4301da177e4SLinus Torvalds struct afs_super_info *as; 4311da177e4SLinus Torvalds unsigned fpos; 4321da177e4SLinus Torvalds int ret; 4331da177e4SLinus Torvalds 43408e0e7c8SDavid Howells _enter("{%lu},%p{%s},", dir->i_ino, dentry, dentry->d_name.name); 4351da177e4SLinus Torvalds 4361da177e4SLinus Torvalds as = dir->i_sb->s_fs_info; 4371da177e4SLinus Torvalds 4381da177e4SLinus Torvalds /* search the directory */ 4391da177e4SLinus Torvalds cookie.name = dentry->d_name.name; 4401da177e4SLinus Torvalds cookie.nlen = dentry->d_name.len; 4411da177e4SLinus Torvalds cookie.fid.vid = as->volume->vid; 4421da177e4SLinus Torvalds cookie.found = 0; 4431da177e4SLinus Torvalds 4441da177e4SLinus Torvalds fpos = 0; 4451da177e4SLinus Torvalds ret = afs_dir_iterate(dir, &fpos, &cookie, afs_dir_lookup_filldir); 4461da177e4SLinus Torvalds if (ret < 0) { 44708e0e7c8SDavid Howells _leave(" = %d [iter]", ret); 44808e0e7c8SDavid Howells return ret; 4491da177e4SLinus Torvalds } 4501da177e4SLinus Torvalds 4511da177e4SLinus Torvalds ret = -ENOENT; 4521da177e4SLinus Torvalds if (!cookie.found) { 45308e0e7c8SDavid Howells _leave(" = -ENOENT [not found]"); 45408e0e7c8SDavid Howells return -ENOENT; 45508e0e7c8SDavid Howells } 45608e0e7c8SDavid Howells 45708e0e7c8SDavid Howells *fid = cookie.fid; 45808e0e7c8SDavid Howells _leave(" = 0 { vn=%u u=%u }", fid->vnode, fid->unique); 45908e0e7c8SDavid Howells return 0; 46008e0e7c8SDavid Howells } 46108e0e7c8SDavid Howells 46208e0e7c8SDavid Howells /* 46308e0e7c8SDavid Howells * look up an entry in a directory 46408e0e7c8SDavid Howells */ 46508e0e7c8SDavid Howells static struct dentry *afs_dir_lookup(struct inode *dir, struct dentry *dentry, 46608e0e7c8SDavid Howells struct nameidata *nd) 46708e0e7c8SDavid Howells { 46808e0e7c8SDavid Howells struct afs_vnode *vnode; 46908e0e7c8SDavid Howells struct afs_fid fid; 47008e0e7c8SDavid Howells struct inode *inode; 47108e0e7c8SDavid Howells int ret; 47208e0e7c8SDavid Howells 47308e0e7c8SDavid Howells _enter("{%lu},%p{%s}", dir->i_ino, dentry, dentry->d_name.name); 47408e0e7c8SDavid Howells 47508e0e7c8SDavid Howells if (dentry->d_name.len > 255) { 47608e0e7c8SDavid Howells _leave(" = -ENAMETOOLONG"); 47708e0e7c8SDavid Howells return ERR_PTR(-ENAMETOOLONG); 47808e0e7c8SDavid Howells } 47908e0e7c8SDavid Howells 48008e0e7c8SDavid Howells vnode = AFS_FS_I(dir); 48108e0e7c8SDavid Howells if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) { 48208e0e7c8SDavid Howells _leave(" = -ESTALE"); 48308e0e7c8SDavid Howells return ERR_PTR(-ESTALE); 48408e0e7c8SDavid Howells } 48508e0e7c8SDavid Howells 48608e0e7c8SDavid Howells ret = afs_do_lookup(dir, dentry, &fid); 48708e0e7c8SDavid Howells if (ret < 0) { 48808e0e7c8SDavid Howells _leave(" = %d [do]", ret); 4891da177e4SLinus Torvalds return ERR_PTR(ret); 4901da177e4SLinus Torvalds } 4911da177e4SLinus Torvalds 4921da177e4SLinus Torvalds /* instantiate the dentry */ 49308e0e7c8SDavid Howells inode = afs_iget(dir->i_sb, &fid); 49408e0e7c8SDavid Howells if (IS_ERR(inode)) { 49508e0e7c8SDavid Howells _leave(" = %ld", PTR_ERR(inode)); 49608e0e7c8SDavid Howells return ERR_PTR(PTR_ERR(inode)); 4971da177e4SLinus Torvalds } 4981da177e4SLinus Torvalds 4991da177e4SLinus Torvalds dentry->d_op = &afs_fs_dentry_operations; 5001da177e4SLinus Torvalds 5011da177e4SLinus Torvalds d_add(dentry, inode); 5021da177e4SLinus Torvalds _leave(" = 0 { vn=%u u=%u } -> { ino=%lu v=%lu }", 50308e0e7c8SDavid Howells fid.vnode, 50408e0e7c8SDavid Howells fid.unique, 5051da177e4SLinus Torvalds dentry->d_inode->i_ino, 5061da177e4SLinus Torvalds dentry->d_inode->i_version); 5071da177e4SLinus Torvalds 5081da177e4SLinus Torvalds return NULL; 509ec26815aSDavid Howells } 5101da177e4SLinus Torvalds 5111da177e4SLinus Torvalds /* 51208e0e7c8SDavid Howells * propagate changed and modified flags on a directory to all the children of 51308e0e7c8SDavid Howells * that directory as they may indicate that the ACL on the dir has changed, 51408e0e7c8SDavid Howells * potentially rendering the child inaccessible or that a file has been deleted 51508e0e7c8SDavid Howells * or renamed 51608e0e7c8SDavid Howells */ 51708e0e7c8SDavid Howells static void afs_propagate_dir_changes(struct dentry *dir) 51808e0e7c8SDavid Howells { 51908e0e7c8SDavid Howells struct dentry *child; 52008e0e7c8SDavid Howells bool c, m; 52108e0e7c8SDavid Howells 52208e0e7c8SDavid Howells c = test_bit(AFS_VNODE_CHANGED, &AFS_FS_I(dir->d_inode)->flags); 52308e0e7c8SDavid Howells m = test_bit(AFS_VNODE_MODIFIED, &AFS_FS_I(dir->d_inode)->flags); 52408e0e7c8SDavid Howells 52508e0e7c8SDavid Howells _enter("{%d,%d}", c, m); 52608e0e7c8SDavid Howells 52708e0e7c8SDavid Howells spin_lock(&dir->d_lock); 52808e0e7c8SDavid Howells 52908e0e7c8SDavid Howells list_for_each_entry(child, &dir->d_subdirs, d_u.d_child) { 53008e0e7c8SDavid Howells if (child->d_inode) { 53108e0e7c8SDavid Howells struct afs_vnode *vnode; 53208e0e7c8SDavid Howells 53308e0e7c8SDavid Howells _debug("tag %s", child->d_name.name); 53408e0e7c8SDavid Howells vnode = AFS_FS_I(child->d_inode); 53508e0e7c8SDavid Howells if (c) 53608e0e7c8SDavid Howells set_bit(AFS_VNODE_DIR_CHANGED, &vnode->flags); 53708e0e7c8SDavid Howells if (m) 53808e0e7c8SDavid Howells set_bit(AFS_VNODE_DIR_MODIFIED, &vnode->flags); 53908e0e7c8SDavid Howells } 54008e0e7c8SDavid Howells } 54108e0e7c8SDavid Howells 54208e0e7c8SDavid Howells spin_unlock(&dir->d_lock); 54308e0e7c8SDavid Howells } 54408e0e7c8SDavid Howells 54508e0e7c8SDavid Howells /* 5461da177e4SLinus Torvalds * check that a dentry lookup hit has found a valid entry 5471da177e4SLinus Torvalds * - NOTE! the hit can be a negative hit too, so we can't assume we have an 5481da177e4SLinus Torvalds * inode 54908e0e7c8SDavid Howells * - there are several things we need to check 55008e0e7c8SDavid Howells * - parent dir data changes (rm, rmdir, rename, mkdir, create, link, 55108e0e7c8SDavid Howells * symlink) 55208e0e7c8SDavid Howells * - parent dir metadata changed (security changes) 55308e0e7c8SDavid Howells * - dentry data changed (write, truncate) 55408e0e7c8SDavid Howells * - dentry metadata changed (security changes) 5551da177e4SLinus Torvalds */ 5561da177e4SLinus Torvalds static int afs_d_revalidate(struct dentry *dentry, struct nameidata *nd) 5571da177e4SLinus Torvalds { 55808e0e7c8SDavid Howells struct afs_vnode *vnode; 55908e0e7c8SDavid Howells struct afs_fid fid; 5601da177e4SLinus Torvalds struct dentry *parent; 5611da177e4SLinus Torvalds struct inode *inode, *dir; 5621da177e4SLinus Torvalds int ret; 5631da177e4SLinus Torvalds 56408e0e7c8SDavid Howells vnode = AFS_FS_I(dentry->d_inode); 56508e0e7c8SDavid Howells 56608e0e7c8SDavid Howells _enter("{sb=%p n=%s fl=%lx},", 56708e0e7c8SDavid Howells dentry->d_sb, dentry->d_name.name, vnode->flags); 5681da177e4SLinus Torvalds 5691da177e4SLinus Torvalds /* lock down the parent dentry so we can peer at it */ 57008e0e7c8SDavid Howells parent = dget_parent(dentry); 5711da177e4SLinus Torvalds 5721da177e4SLinus Torvalds dir = parent->d_inode; 5731da177e4SLinus Torvalds inode = dentry->d_inode; 5741da177e4SLinus Torvalds 5751da177e4SLinus Torvalds /* handle a negative dentry */ 5761da177e4SLinus Torvalds if (!inode) 5771da177e4SLinus Torvalds goto out_bad; 5781da177e4SLinus Torvalds 5791da177e4SLinus Torvalds /* handle a bad inode */ 5801da177e4SLinus Torvalds if (is_bad_inode(inode)) { 5811da177e4SLinus Torvalds printk("kAFS: afs_d_revalidate: %s/%s has bad inode\n", 58208e0e7c8SDavid Howells parent->d_name.name, dentry->d_name.name); 5831da177e4SLinus Torvalds goto out_bad; 5841da177e4SLinus Torvalds } 5851da177e4SLinus Torvalds 58608e0e7c8SDavid Howells /* check that this dirent still exists if the directory's contents were 58708e0e7c8SDavid Howells * modified */ 58808e0e7c8SDavid Howells if (test_bit(AFS_VNODE_DELETED, &AFS_FS_I(dir)->flags)) { 5891da177e4SLinus Torvalds _debug("%s: parent dir deleted", dentry->d_name.name); 5901da177e4SLinus Torvalds goto out_bad; 5911da177e4SLinus Torvalds } 5921da177e4SLinus Torvalds 59308e0e7c8SDavid Howells if (test_and_clear_bit(AFS_VNODE_DIR_MODIFIED, &vnode->flags)) { 59408e0e7c8SDavid Howells /* rm/rmdir/rename may have occurred */ 59508e0e7c8SDavid Howells _debug("dir modified"); 5961da177e4SLinus Torvalds 5971da177e4SLinus Torvalds /* search the directory for this vnode */ 59808e0e7c8SDavid Howells ret = afs_do_lookup(dir, dentry, &fid); 59908e0e7c8SDavid Howells if (ret == -ENOENT) { 60008e0e7c8SDavid Howells _debug("%s: dirent not found", dentry->d_name.name); 60108e0e7c8SDavid Howells goto not_found; 60208e0e7c8SDavid Howells } 6031da177e4SLinus Torvalds if (ret < 0) { 6041da177e4SLinus Torvalds _debug("failed to iterate dir %s: %d", 6051da177e4SLinus Torvalds parent->d_name.name, ret); 6061da177e4SLinus Torvalds goto out_bad; 6071da177e4SLinus Torvalds } 6081da177e4SLinus Torvalds 6091da177e4SLinus Torvalds /* if the vnode ID has changed, then the dirent points to a 6101da177e4SLinus Torvalds * different file */ 61108e0e7c8SDavid Howells if (fid.vnode != vnode->fid.vnode) { 61208e0e7c8SDavid Howells _debug("%s: dirent changed [%u != %u]", 61308e0e7c8SDavid Howells dentry->d_name.name, fid.vnode, 61408e0e7c8SDavid Howells vnode->fid.vnode); 6151da177e4SLinus Torvalds goto not_found; 6161da177e4SLinus Torvalds } 6171da177e4SLinus Torvalds 6181da177e4SLinus Torvalds /* if the vnode ID uniqifier has changed, then the file has 6191da177e4SLinus Torvalds * been deleted */ 62008e0e7c8SDavid Howells if (fid.unique != vnode->fid.unique) { 6211da177e4SLinus Torvalds _debug("%s: file deleted (uq %u -> %u I:%lu)", 62208e0e7c8SDavid Howells dentry->d_name.name, fid.unique, 62308e0e7c8SDavid Howells vnode->fid.unique, inode->i_version); 62408e0e7c8SDavid Howells spin_lock(&vnode->lock); 62508e0e7c8SDavid Howells set_bit(AFS_VNODE_DELETED, &vnode->flags); 62608e0e7c8SDavid Howells spin_unlock(&vnode->lock); 6271da177e4SLinus Torvalds invalidate_remote_inode(inode); 6281da177e4SLinus Torvalds goto out_bad; 6291da177e4SLinus Torvalds } 6301da177e4SLinus Torvalds } 6311da177e4SLinus Torvalds 63208e0e7c8SDavid Howells /* if the directory's metadata were changed then the security may be 63308e0e7c8SDavid Howells * different and we may no longer have access */ 63408e0e7c8SDavid Howells mutex_lock(&vnode->cb_broken_lock); 63508e0e7c8SDavid Howells 63608e0e7c8SDavid Howells if (test_and_clear_bit(AFS_VNODE_DIR_CHANGED, &vnode->flags) || 63708e0e7c8SDavid Howells test_bit(AFS_VNODE_CB_BROKEN, &vnode->flags)) { 63808e0e7c8SDavid Howells _debug("%s: changed", dentry->d_name.name); 63908e0e7c8SDavid Howells set_bit(AFS_VNODE_CB_BROKEN, &vnode->flags); 64008e0e7c8SDavid Howells if (afs_vnode_fetch_status(vnode) < 0) { 64108e0e7c8SDavid Howells mutex_unlock(&vnode->cb_broken_lock); 64208e0e7c8SDavid Howells goto out_bad; 64308e0e7c8SDavid Howells } 64408e0e7c8SDavid Howells } 64508e0e7c8SDavid Howells 64608e0e7c8SDavid Howells if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) { 64708e0e7c8SDavid Howells _debug("%s: file already deleted", dentry->d_name.name); 64808e0e7c8SDavid Howells mutex_unlock(&vnode->cb_broken_lock); 64908e0e7c8SDavid Howells goto out_bad; 65008e0e7c8SDavid Howells } 65108e0e7c8SDavid Howells 65208e0e7c8SDavid Howells /* if the vnode's data version number changed then its contents are 65308e0e7c8SDavid Howells * different */ 65408e0e7c8SDavid Howells if (test_and_clear_bit(AFS_VNODE_ZAP_DATA, &vnode->flags)) { 65508e0e7c8SDavid Howells _debug("zap data"); 65608e0e7c8SDavid Howells invalidate_remote_inode(inode); 65708e0e7c8SDavid Howells } 65808e0e7c8SDavid Howells 65908e0e7c8SDavid Howells if (S_ISDIR(inode->i_mode) && 66008e0e7c8SDavid Howells (test_bit(AFS_VNODE_CHANGED, &vnode->flags) || 66108e0e7c8SDavid Howells test_bit(AFS_VNODE_MODIFIED, &vnode->flags))) 66208e0e7c8SDavid Howells afs_propagate_dir_changes(dentry); 66308e0e7c8SDavid Howells 66408e0e7c8SDavid Howells clear_bit(AFS_VNODE_CHANGED, &vnode->flags); 66508e0e7c8SDavid Howells clear_bit(AFS_VNODE_MODIFIED, &vnode->flags); 66608e0e7c8SDavid Howells mutex_unlock(&vnode->cb_broken_lock); 66708e0e7c8SDavid Howells 6681da177e4SLinus Torvalds out_valid: 6691da177e4SLinus Torvalds dput(parent); 6701da177e4SLinus Torvalds _leave(" = 1 [valid]"); 6711da177e4SLinus Torvalds return 1; 6721da177e4SLinus Torvalds 6731da177e4SLinus Torvalds /* the dirent, if it exists, now points to a different vnode */ 6741da177e4SLinus Torvalds not_found: 6751da177e4SLinus Torvalds spin_lock(&dentry->d_lock); 6761da177e4SLinus Torvalds dentry->d_flags |= DCACHE_NFSFS_RENAMED; 6771da177e4SLinus Torvalds spin_unlock(&dentry->d_lock); 6781da177e4SLinus Torvalds 6791da177e4SLinus Torvalds out_bad: 6801da177e4SLinus Torvalds if (inode) { 6811da177e4SLinus Torvalds /* don't unhash if we have submounts */ 6821da177e4SLinus Torvalds if (have_submounts(dentry)) 6831da177e4SLinus Torvalds goto out_valid; 6841da177e4SLinus Torvalds } 6851da177e4SLinus Torvalds 6861da177e4SLinus Torvalds _debug("dropping dentry %s/%s", 68708e0e7c8SDavid Howells parent->d_name.name, dentry->d_name.name); 68808e0e7c8SDavid Howells shrink_dcache_parent(dentry); 6891da177e4SLinus Torvalds d_drop(dentry); 6901da177e4SLinus Torvalds dput(parent); 6911da177e4SLinus Torvalds 6921da177e4SLinus Torvalds _leave(" = 0 [bad]"); 6931da177e4SLinus Torvalds return 0; 694ec26815aSDavid Howells } 6951da177e4SLinus Torvalds 6961da177e4SLinus Torvalds /* 6971da177e4SLinus Torvalds * allow the VFS to enquire as to whether a dentry should be unhashed (mustn't 6981da177e4SLinus Torvalds * sleep) 6991da177e4SLinus Torvalds * - called from dput() when d_count is going to 0. 7001da177e4SLinus Torvalds * - return 1 to request dentry be unhashed, 0 otherwise 7011da177e4SLinus Torvalds */ 7021da177e4SLinus Torvalds static int afs_d_delete(struct dentry *dentry) 7031da177e4SLinus Torvalds { 7041da177e4SLinus Torvalds _enter("%s", dentry->d_name.name); 7051da177e4SLinus Torvalds 7061da177e4SLinus Torvalds if (dentry->d_flags & DCACHE_NFSFS_RENAMED) 7071da177e4SLinus Torvalds goto zap; 7081da177e4SLinus Torvalds 70908e0e7c8SDavid Howells if (dentry->d_inode && 71008e0e7c8SDavid Howells test_bit(AFS_VNODE_DELETED, &AFS_FS_I(dentry->d_inode)->flags)) 7111da177e4SLinus Torvalds goto zap; 7121da177e4SLinus Torvalds 7131da177e4SLinus Torvalds _leave(" = 0 [keep]"); 7141da177e4SLinus Torvalds return 0; 7151da177e4SLinus Torvalds 7161da177e4SLinus Torvalds zap: 7171da177e4SLinus Torvalds _leave(" = 1 [zap]"); 7181da177e4SLinus Torvalds return 1; 719ec26815aSDavid Howells } 720