1457c8996SThomas Gleixner // SPDX-License-Identifier: GPL-2.0-only 21da177e4SLinus Torvalds /* 31da177e4SLinus Torvalds * fs/libfs.c 41da177e4SLinus Torvalds * Library for filesystems writers. 51da177e4SLinus Torvalds */ 61da177e4SLinus Torvalds 7ac13a829SFabian Frederick #include <linux/blkdev.h> 8630d9c47SPaul Gortmaker #include <linux/export.h> 91da177e4SLinus Torvalds #include <linux/pagemap.h> 105a0e3ad6STejun Heo #include <linux/slab.h> 115b825c3aSIngo Molnar #include <linux/cred.h> 121da177e4SLinus Torvalds #include <linux/mount.h> 131da177e4SLinus Torvalds #include <linux/vfs.h> 147bb46a67Snpiggin@suse.de #include <linux/quotaops.h> 157cf34c76SIngo Molnar #include <linux/mutex.h> 1687dc800bSAl Viro #include <linux/namei.h> 172596110aSChristoph Hellwig #include <linux/exportfs.h> 18d5aacad5SAl Viro #include <linux/writeback.h> 19ff01bb48SAl Viro #include <linux/buffer_head.h> /* sync_mapping_buffers */ 2031d6d5ceSDavid Howells #include <linux/fs_context.h> 2131d6d5ceSDavid Howells #include <linux/pseudo_fs.h> 22a3d1e7ebSAl Viro #include <linux/fsnotify.h> 23c843843eSDaniel Rosenberg #include <linux/unicode.h> 24c843843eSDaniel Rosenberg #include <linux/fscrypt.h> 257cf34c76SIngo Molnar 267c0f6ba6SLinus Torvalds #include <linux/uaccess.h> 271da177e4SLinus Torvalds 28a4464dbcSAl Viro #include "internal.h" 29a4464dbcSAl Viro 30*549c7297SChristian Brauner int simple_getattr(struct user_namespace *mnt_userns, const struct path *path, 31*549c7297SChristian Brauner struct kstat *stat, u32 request_mask, 32*549c7297SChristian Brauner unsigned int query_flags) 331da177e4SLinus Torvalds { 34a528d35eSDavid Howells struct inode *inode = d_inode(path->dentry); 350d56a451SChristian Brauner generic_fillattr(&init_user_ns, inode, stat); 3609cbfeafSKirill A. Shutemov stat->blocks = inode->i_mapping->nrpages << (PAGE_SHIFT - 9); 371da177e4SLinus Torvalds return 0; 381da177e4SLinus Torvalds } 3912f38872SAl Viro EXPORT_SYMBOL(simple_getattr); 401da177e4SLinus Torvalds 41726c3342SDavid Howells int simple_statfs(struct dentry *dentry, struct kstatfs *buf) 421da177e4SLinus Torvalds { 43726c3342SDavid Howells buf->f_type = dentry->d_sb->s_magic; 4409cbfeafSKirill A. Shutemov buf->f_bsize = PAGE_SIZE; 451da177e4SLinus Torvalds buf->f_namelen = NAME_MAX; 461da177e4SLinus Torvalds return 0; 471da177e4SLinus Torvalds } 4812f38872SAl Viro EXPORT_SYMBOL(simple_statfs); 491da177e4SLinus Torvalds 501da177e4SLinus Torvalds /* 511da177e4SLinus Torvalds * Retaining negative dentries for an in-memory filesystem just wastes 521da177e4SLinus Torvalds * memory and lookup time: arrange for them to be deleted immediately. 531da177e4SLinus Torvalds */ 54b26d4cd3SAl Viro int always_delete_dentry(const struct dentry *dentry) 551da177e4SLinus Torvalds { 561da177e4SLinus Torvalds return 1; 571da177e4SLinus Torvalds } 58b26d4cd3SAl Viro EXPORT_SYMBOL(always_delete_dentry); 59b26d4cd3SAl Viro 60b26d4cd3SAl Viro const struct dentry_operations simple_dentry_operations = { 61b26d4cd3SAl Viro .d_delete = always_delete_dentry, 62b26d4cd3SAl Viro }; 63b26d4cd3SAl Viro EXPORT_SYMBOL(simple_dentry_operations); 641da177e4SLinus Torvalds 651da177e4SLinus Torvalds /* 661da177e4SLinus Torvalds * Lookup the data. This is trivial - if the dentry didn't already 671da177e4SLinus Torvalds * exist, we know it is negative. Set d_op to delete negative dentries. 681da177e4SLinus Torvalds */ 6900cd8dd3SAl Viro struct dentry *simple_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) 701da177e4SLinus Torvalds { 711da177e4SLinus Torvalds if (dentry->d_name.len > NAME_MAX) 721da177e4SLinus Torvalds return ERR_PTR(-ENAMETOOLONG); 7374931da7SAl Viro if (!dentry->d_sb->s_d_op) 74fb045adbSNick Piggin d_set_d_op(dentry, &simple_dentry_operations); 751da177e4SLinus Torvalds d_add(dentry, NULL); 761da177e4SLinus Torvalds return NULL; 771da177e4SLinus Torvalds } 7812f38872SAl Viro EXPORT_SYMBOL(simple_lookup); 791da177e4SLinus Torvalds 801da177e4SLinus Torvalds int dcache_dir_open(struct inode *inode, struct file *file) 811da177e4SLinus Torvalds { 82ba65dc5eSAl Viro file->private_data = d_alloc_cursor(file->f_path.dentry); 831da177e4SLinus Torvalds 841da177e4SLinus Torvalds return file->private_data ? 0 : -ENOMEM; 851da177e4SLinus Torvalds } 8612f38872SAl Viro EXPORT_SYMBOL(dcache_dir_open); 871da177e4SLinus Torvalds 881da177e4SLinus Torvalds int dcache_dir_close(struct inode *inode, struct file *file) 891da177e4SLinus Torvalds { 901da177e4SLinus Torvalds dput(file->private_data); 911da177e4SLinus Torvalds return 0; 921da177e4SLinus Torvalds } 9312f38872SAl Viro EXPORT_SYMBOL(dcache_dir_close); 941da177e4SLinus Torvalds 954f42c1b5SAl Viro /* parent is locked at least shared */ 96d4f4de5eSAl Viro /* 97d4f4de5eSAl Viro * Returns an element of siblings' list. 98d4f4de5eSAl Viro * We are looking for <count>th positive after <p>; if 9926b6c984SAl Viro * found, dentry is grabbed and returned to caller. 10026b6c984SAl Viro * If no such element exists, NULL is returned. 101d4f4de5eSAl Viro */ 10226b6c984SAl Viro static struct dentry *scan_positives(struct dentry *cursor, 103d4f4de5eSAl Viro struct list_head *p, 104d4f4de5eSAl Viro loff_t count, 10526b6c984SAl Viro struct dentry *last) 1064f42c1b5SAl Viro { 107d4f4de5eSAl Viro struct dentry *dentry = cursor->d_parent, *found = NULL; 1084f42c1b5SAl Viro 109d4f4de5eSAl Viro spin_lock(&dentry->d_lock); 110d4f4de5eSAl Viro while ((p = p->next) != &dentry->d_subdirs) { 1114f42c1b5SAl Viro struct dentry *d = list_entry(p, struct dentry, d_child); 112d4f4de5eSAl Viro // we must at least skip cursors, to avoid livelocks 113d4f4de5eSAl Viro if (d->d_flags & DCACHE_DENTRY_CURSOR) 114d4f4de5eSAl Viro continue; 115d4f4de5eSAl Viro if (simple_positive(d) && !--count) { 116d4f4de5eSAl Viro spin_lock_nested(&d->d_lock, DENTRY_D_LOCK_NESTED); 117d4f4de5eSAl Viro if (simple_positive(d)) 118d4f4de5eSAl Viro found = dget_dlock(d); 119d4f4de5eSAl Viro spin_unlock(&d->d_lock); 120d4f4de5eSAl Viro if (likely(found)) 1214f42c1b5SAl Viro break; 122d4f4de5eSAl Viro count = 1; 123d4f4de5eSAl Viro } 124d4f4de5eSAl Viro if (need_resched()) { 125d4f4de5eSAl Viro list_move(&cursor->d_child, p); 126d4f4de5eSAl Viro p = &cursor->d_child; 127d4f4de5eSAl Viro spin_unlock(&dentry->d_lock); 128d4f4de5eSAl Viro cond_resched(); 129d4f4de5eSAl Viro spin_lock(&dentry->d_lock); 1304f42c1b5SAl Viro } 1314f42c1b5SAl Viro } 132d4f4de5eSAl Viro spin_unlock(&dentry->d_lock); 13326b6c984SAl Viro dput(last); 13426b6c984SAl Viro return found; 1354f42c1b5SAl Viro } 1364f42c1b5SAl Viro 137965c8e59SAndrew Morton loff_t dcache_dir_lseek(struct file *file, loff_t offset, int whence) 1381da177e4SLinus Torvalds { 1392fd6b7f5SNick Piggin struct dentry *dentry = file->f_path.dentry; 140965c8e59SAndrew Morton switch (whence) { 1411da177e4SLinus Torvalds case 1: 1421da177e4SLinus Torvalds offset += file->f_pos; 143df561f66SGustavo A. R. Silva fallthrough; 1441da177e4SLinus Torvalds case 0: 1451da177e4SLinus Torvalds if (offset >= 0) 1461da177e4SLinus Torvalds break; 147df561f66SGustavo A. R. Silva fallthrough; 1481da177e4SLinus Torvalds default: 1491da177e4SLinus Torvalds return -EINVAL; 1501da177e4SLinus Torvalds } 1511da177e4SLinus Torvalds if (offset != file->f_pos) { 1521da177e4SLinus Torvalds struct dentry *cursor = file->private_data; 153d4f4de5eSAl Viro struct dentry *to = NULL; 1541da177e4SLinus Torvalds 155274f5b04SAl Viro inode_lock_shared(dentry->d_inode); 156d4f4de5eSAl Viro 15726b6c984SAl Viro if (offset > 2) 15826b6c984SAl Viro to = scan_positives(cursor, &dentry->d_subdirs, 15926b6c984SAl Viro offset - 2, NULL); 160d4f4de5eSAl Viro spin_lock(&dentry->d_lock); 16126b6c984SAl Viro if (to) 16226b6c984SAl Viro list_move(&cursor->d_child, &to->d_child); 16326b6c984SAl Viro else 164d4f4de5eSAl Viro list_del_init(&cursor->d_child); 165d4f4de5eSAl Viro spin_unlock(&dentry->d_lock); 166d4f4de5eSAl Viro dput(to); 167d4f4de5eSAl Viro 16826b6c984SAl Viro file->f_pos = offset; 16926b6c984SAl Viro 170d4f4de5eSAl Viro inode_unlock_shared(dentry->d_inode); 1711da177e4SLinus Torvalds } 1721da177e4SLinus Torvalds return offset; 1731da177e4SLinus Torvalds } 17412f38872SAl Viro EXPORT_SYMBOL(dcache_dir_lseek); 1751da177e4SLinus Torvalds 1761da177e4SLinus Torvalds /* Relationship between i_mode and the DT_xxx types */ 1771da177e4SLinus Torvalds static inline unsigned char dt_type(struct inode *inode) 1781da177e4SLinus Torvalds { 1791da177e4SLinus Torvalds return (inode->i_mode >> 12) & 15; 1801da177e4SLinus Torvalds } 1811da177e4SLinus Torvalds 1821da177e4SLinus Torvalds /* 1831da177e4SLinus Torvalds * Directory is locked and all positive dentries in it are safe, since 1841da177e4SLinus Torvalds * for ramfs-type trees they can't go away without unlink() or rmdir(), 1851da177e4SLinus Torvalds * both impossible due to the lock on directory. 1861da177e4SLinus Torvalds */ 1871da177e4SLinus Torvalds 1885f99f4e7SAl Viro int dcache_readdir(struct file *file, struct dir_context *ctx) 1891da177e4SLinus Torvalds { 1905f99f4e7SAl Viro struct dentry *dentry = file->f_path.dentry; 1915f99f4e7SAl Viro struct dentry *cursor = file->private_data; 192d4f4de5eSAl Viro struct list_head *anchor = &dentry->d_subdirs; 193d4f4de5eSAl Viro struct dentry *next = NULL; 194d4f4de5eSAl Viro struct list_head *p; 1951da177e4SLinus Torvalds 1965f99f4e7SAl Viro if (!dir_emit_dots(file, ctx)) 1975f99f4e7SAl Viro return 0; 1984f42c1b5SAl Viro 1995f99f4e7SAl Viro if (ctx->pos == 2) 200d4f4de5eSAl Viro p = anchor; 20126b6c984SAl Viro else if (!list_empty(&cursor->d_child)) 202d4f4de5eSAl Viro p = &cursor->d_child; 20326b6c984SAl Viro else 20426b6c984SAl Viro return 0; 205d4f4de5eSAl Viro 20626b6c984SAl Viro while ((next = scan_positives(cursor, p, 1, next)) != NULL) { 2075f99f4e7SAl Viro if (!dir_emit(ctx, next->d_name.name, next->d_name.len, 208dea655c2SDavid Howells d_inode(next)->i_ino, dt_type(d_inode(next)))) 2094f42c1b5SAl Viro break; 2105f99f4e7SAl Viro ctx->pos++; 21126b6c984SAl Viro p = &next->d_child; 2121da177e4SLinus Torvalds } 213d4f4de5eSAl Viro spin_lock(&dentry->d_lock); 21426b6c984SAl Viro if (next) 21526b6c984SAl Viro list_move_tail(&cursor->d_child, &next->d_child); 21626b6c984SAl Viro else 21726b6c984SAl Viro list_del_init(&cursor->d_child); 218d4f4de5eSAl Viro spin_unlock(&dentry->d_lock); 219d4f4de5eSAl Viro dput(next); 220d4f4de5eSAl Viro 2211da177e4SLinus Torvalds return 0; 2221da177e4SLinus Torvalds } 22312f38872SAl Viro EXPORT_SYMBOL(dcache_readdir); 2241da177e4SLinus Torvalds 2251da177e4SLinus Torvalds ssize_t generic_read_dir(struct file *filp, char __user *buf, size_t siz, loff_t *ppos) 2261da177e4SLinus Torvalds { 2271da177e4SLinus Torvalds return -EISDIR; 2281da177e4SLinus Torvalds } 22912f38872SAl Viro EXPORT_SYMBOL(generic_read_dir); 2301da177e4SLinus Torvalds 2314b6f5d20SArjan van de Ven const struct file_operations simple_dir_operations = { 2321da177e4SLinus Torvalds .open = dcache_dir_open, 2331da177e4SLinus Torvalds .release = dcache_dir_close, 2341da177e4SLinus Torvalds .llseek = dcache_dir_lseek, 2351da177e4SLinus Torvalds .read = generic_read_dir, 2364e82901cSAl Viro .iterate_shared = dcache_readdir, 2371b061d92SChristoph Hellwig .fsync = noop_fsync, 2381da177e4SLinus Torvalds }; 23912f38872SAl Viro EXPORT_SYMBOL(simple_dir_operations); 2401da177e4SLinus Torvalds 24192e1d5beSArjan van de Ven const struct inode_operations simple_dir_inode_operations = { 2421da177e4SLinus Torvalds .lookup = simple_lookup, 2431da177e4SLinus Torvalds }; 24412f38872SAl Viro EXPORT_SYMBOL(simple_dir_inode_operations); 2451da177e4SLinus Torvalds 246a3d1e7ebSAl Viro static struct dentry *find_next_child(struct dentry *parent, struct dentry *prev) 247a3d1e7ebSAl Viro { 248a3d1e7ebSAl Viro struct dentry *child = NULL; 249a3d1e7ebSAl Viro struct list_head *p = prev ? &prev->d_child : &parent->d_subdirs; 250a3d1e7ebSAl Viro 251a3d1e7ebSAl Viro spin_lock(&parent->d_lock); 252a3d1e7ebSAl Viro while ((p = p->next) != &parent->d_subdirs) { 253a3d1e7ebSAl Viro struct dentry *d = container_of(p, struct dentry, d_child); 254a3d1e7ebSAl Viro if (simple_positive(d)) { 255a3d1e7ebSAl Viro spin_lock_nested(&d->d_lock, DENTRY_D_LOCK_NESTED); 256a3d1e7ebSAl Viro if (simple_positive(d)) 257a3d1e7ebSAl Viro child = dget_dlock(d); 258a3d1e7ebSAl Viro spin_unlock(&d->d_lock); 259a3d1e7ebSAl Viro if (likely(child)) 260a3d1e7ebSAl Viro break; 261a3d1e7ebSAl Viro } 262a3d1e7ebSAl Viro } 263a3d1e7ebSAl Viro spin_unlock(&parent->d_lock); 264a3d1e7ebSAl Viro dput(prev); 265a3d1e7ebSAl Viro return child; 266a3d1e7ebSAl Viro } 267a3d1e7ebSAl Viro 268a3d1e7ebSAl Viro void simple_recursive_removal(struct dentry *dentry, 269a3d1e7ebSAl Viro void (*callback)(struct dentry *)) 270a3d1e7ebSAl Viro { 271a3d1e7ebSAl Viro struct dentry *this = dget(dentry); 272a3d1e7ebSAl Viro while (true) { 273a3d1e7ebSAl Viro struct dentry *victim = NULL, *child; 274a3d1e7ebSAl Viro struct inode *inode = this->d_inode; 275a3d1e7ebSAl Viro 276a3d1e7ebSAl Viro inode_lock(inode); 277a3d1e7ebSAl Viro if (d_is_dir(this)) 278a3d1e7ebSAl Viro inode->i_flags |= S_DEAD; 279a3d1e7ebSAl Viro while ((child = find_next_child(this, victim)) == NULL) { 280a3d1e7ebSAl Viro // kill and ascend 281a3d1e7ebSAl Viro // update metadata while it's still locked 282a3d1e7ebSAl Viro inode->i_ctime = current_time(inode); 283a3d1e7ebSAl Viro clear_nlink(inode); 284a3d1e7ebSAl Viro inode_unlock(inode); 285a3d1e7ebSAl Viro victim = this; 286a3d1e7ebSAl Viro this = this->d_parent; 287a3d1e7ebSAl Viro inode = this->d_inode; 288a3d1e7ebSAl Viro inode_lock(inode); 289a3d1e7ebSAl Viro if (simple_positive(victim)) { 290a3d1e7ebSAl Viro d_invalidate(victim); // avoid lost mounts 291a3d1e7ebSAl Viro if (d_is_dir(victim)) 292a3d1e7ebSAl Viro fsnotify_rmdir(inode, victim); 293a3d1e7ebSAl Viro else 294a3d1e7ebSAl Viro fsnotify_unlink(inode, victim); 295a3d1e7ebSAl Viro if (callback) 296a3d1e7ebSAl Viro callback(victim); 297a3d1e7ebSAl Viro dput(victim); // unpin it 298a3d1e7ebSAl Viro } 299a3d1e7ebSAl Viro if (victim == dentry) { 300a3d1e7ebSAl Viro inode->i_ctime = inode->i_mtime = 301a3d1e7ebSAl Viro current_time(inode); 302a3d1e7ebSAl Viro if (d_is_dir(dentry)) 303a3d1e7ebSAl Viro drop_nlink(inode); 304a3d1e7ebSAl Viro inode_unlock(inode); 305a3d1e7ebSAl Viro dput(dentry); 306a3d1e7ebSAl Viro return; 307a3d1e7ebSAl Viro } 308a3d1e7ebSAl Viro } 309a3d1e7ebSAl Viro inode_unlock(inode); 310a3d1e7ebSAl Viro this = child; 311a3d1e7ebSAl Viro } 312a3d1e7ebSAl Viro } 313a3d1e7ebSAl Viro EXPORT_SYMBOL(simple_recursive_removal); 314a3d1e7ebSAl Viro 315759b9775SHugh Dickins static const struct super_operations simple_super_operations = { 316759b9775SHugh Dickins .statfs = simple_statfs, 317759b9775SHugh Dickins }; 318759b9775SHugh Dickins 319db2c246aSDavid Howells static int pseudo_fs_fill_super(struct super_block *s, struct fs_context *fc) 3201da177e4SLinus Torvalds { 32131d6d5ceSDavid Howells struct pseudo_fs_context *ctx = fc->fs_private; 3221da177e4SLinus Torvalds struct inode *root; 3231da177e4SLinus Torvalds 32489a4eb4bSJeff Layton s->s_maxbytes = MAX_LFS_FILESIZE; 3253971e1a9SAlex Nixon s->s_blocksize = PAGE_SIZE; 3263971e1a9SAlex Nixon s->s_blocksize_bits = PAGE_SHIFT; 3278d9e46d8SAl Viro s->s_magic = ctx->magic; 3288d9e46d8SAl Viro s->s_op = ctx->ops ?: &simple_super_operations; 3298d9e46d8SAl Viro s->s_xattr = ctx->xattr; 3301da177e4SLinus Torvalds s->s_time_gran = 1; 3311da177e4SLinus Torvalds root = new_inode(s); 3321da177e4SLinus Torvalds if (!root) 333db2c246aSDavid Howells return -ENOMEM; 334db2c246aSDavid Howells 3351a1c9bb4SJeff Layton /* 3361a1c9bb4SJeff Layton * since this is the first inode, make it number 1. New inodes created 3371a1c9bb4SJeff Layton * after this must take care not to collide with it (by passing 3381a1c9bb4SJeff Layton * max_reserved of 1 to iunique). 3391a1c9bb4SJeff Layton */ 3401a1c9bb4SJeff Layton root->i_ino = 1; 3411da177e4SLinus Torvalds root->i_mode = S_IFDIR | S_IRUSR | S_IWUSR; 342078cd827SDeepa Dinamani root->i_atime = root->i_mtime = root->i_ctime = current_time(root); 3438d9e46d8SAl Viro s->s_root = d_make_root(root); 3448d9e46d8SAl Viro if (!s->s_root) 3458d9e46d8SAl Viro return -ENOMEM; 346db2c246aSDavid Howells s->s_d_op = ctx->dops; 347db2c246aSDavid Howells return 0; 3481da177e4SLinus Torvalds } 3491da177e4SLinus Torvalds 350db2c246aSDavid Howells static int pseudo_fs_get_tree(struct fs_context *fc) 351db2c246aSDavid Howells { 3522ac295d4SAl Viro return get_tree_nodev(fc, pseudo_fs_fill_super); 3531da177e4SLinus Torvalds } 35431d6d5ceSDavid Howells 35531d6d5ceSDavid Howells static void pseudo_fs_free(struct fs_context *fc) 35631d6d5ceSDavid Howells { 35731d6d5ceSDavid Howells kfree(fc->fs_private); 35831d6d5ceSDavid Howells } 35931d6d5ceSDavid Howells 36031d6d5ceSDavid Howells static const struct fs_context_operations pseudo_fs_context_ops = { 36131d6d5ceSDavid Howells .free = pseudo_fs_free, 36231d6d5ceSDavid Howells .get_tree = pseudo_fs_get_tree, 36331d6d5ceSDavid Howells }; 36431d6d5ceSDavid Howells 36531d6d5ceSDavid Howells /* 36631d6d5ceSDavid Howells * Common helper for pseudo-filesystems (sockfs, pipefs, bdev - stuff that 36731d6d5ceSDavid Howells * will never be mountable) 36831d6d5ceSDavid Howells */ 36931d6d5ceSDavid Howells struct pseudo_fs_context *init_pseudo(struct fs_context *fc, 37031d6d5ceSDavid Howells unsigned long magic) 37131d6d5ceSDavid Howells { 37231d6d5ceSDavid Howells struct pseudo_fs_context *ctx; 37331d6d5ceSDavid Howells 37431d6d5ceSDavid Howells ctx = kzalloc(sizeof(struct pseudo_fs_context), GFP_KERNEL); 37531d6d5ceSDavid Howells if (likely(ctx)) { 37631d6d5ceSDavid Howells ctx->magic = magic; 37731d6d5ceSDavid Howells fc->fs_private = ctx; 37831d6d5ceSDavid Howells fc->ops = &pseudo_fs_context_ops; 379db2c246aSDavid Howells fc->sb_flags |= SB_NOUSER; 380db2c246aSDavid Howells fc->global = true; 38131d6d5ceSDavid Howells } 38231d6d5ceSDavid Howells return ctx; 38331d6d5ceSDavid Howells } 38431d6d5ceSDavid Howells EXPORT_SYMBOL(init_pseudo); 3851da177e4SLinus Torvalds 38620955e89SStephen Boyd int simple_open(struct inode *inode, struct file *file) 38720955e89SStephen Boyd { 38820955e89SStephen Boyd if (inode->i_private) 38920955e89SStephen Boyd file->private_data = inode->i_private; 39020955e89SStephen Boyd return 0; 39120955e89SStephen Boyd } 39212f38872SAl Viro EXPORT_SYMBOL(simple_open); 39320955e89SStephen Boyd 3941da177e4SLinus Torvalds int simple_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry) 3951da177e4SLinus Torvalds { 396dea655c2SDavid Howells struct inode *inode = d_inode(old_dentry); 3971da177e4SLinus Torvalds 398078cd827SDeepa Dinamani inode->i_ctime = dir->i_ctime = dir->i_mtime = current_time(inode); 399d8c76e6fSDave Hansen inc_nlink(inode); 4007de9c6eeSAl Viro ihold(inode); 4011da177e4SLinus Torvalds dget(dentry); 4021da177e4SLinus Torvalds d_instantiate(dentry, inode); 4031da177e4SLinus Torvalds return 0; 4041da177e4SLinus Torvalds } 40512f38872SAl Viro EXPORT_SYMBOL(simple_link); 4061da177e4SLinus Torvalds 4071da177e4SLinus Torvalds int simple_empty(struct dentry *dentry) 4081da177e4SLinus Torvalds { 4091da177e4SLinus Torvalds struct dentry *child; 4101da177e4SLinus Torvalds int ret = 0; 4111da177e4SLinus Torvalds 4122fd6b7f5SNick Piggin spin_lock(&dentry->d_lock); 413946e51f2SAl Viro list_for_each_entry(child, &dentry->d_subdirs, d_child) { 414da502956SNick Piggin spin_lock_nested(&child->d_lock, DENTRY_D_LOCK_NESTED); 415da502956SNick Piggin if (simple_positive(child)) { 416da502956SNick Piggin spin_unlock(&child->d_lock); 4171da177e4SLinus Torvalds goto out; 418da502956SNick Piggin } 419da502956SNick Piggin spin_unlock(&child->d_lock); 420da502956SNick Piggin } 4211da177e4SLinus Torvalds ret = 1; 4221da177e4SLinus Torvalds out: 4232fd6b7f5SNick Piggin spin_unlock(&dentry->d_lock); 4241da177e4SLinus Torvalds return ret; 4251da177e4SLinus Torvalds } 42612f38872SAl Viro EXPORT_SYMBOL(simple_empty); 4271da177e4SLinus Torvalds 4281da177e4SLinus Torvalds int simple_unlink(struct inode *dir, struct dentry *dentry) 4291da177e4SLinus Torvalds { 430dea655c2SDavid Howells struct inode *inode = d_inode(dentry); 4311da177e4SLinus Torvalds 432078cd827SDeepa Dinamani inode->i_ctime = dir->i_ctime = dir->i_mtime = current_time(inode); 4339a53c3a7SDave Hansen drop_nlink(inode); 4341da177e4SLinus Torvalds dput(dentry); 4351da177e4SLinus Torvalds return 0; 4361da177e4SLinus Torvalds } 43712f38872SAl Viro EXPORT_SYMBOL(simple_unlink); 4381da177e4SLinus Torvalds 4391da177e4SLinus Torvalds int simple_rmdir(struct inode *dir, struct dentry *dentry) 4401da177e4SLinus Torvalds { 4411da177e4SLinus Torvalds if (!simple_empty(dentry)) 4421da177e4SLinus Torvalds return -ENOTEMPTY; 4431da177e4SLinus Torvalds 444dea655c2SDavid Howells drop_nlink(d_inode(dentry)); 4451da177e4SLinus Torvalds simple_unlink(dir, dentry); 4469a53c3a7SDave Hansen drop_nlink(dir); 4471da177e4SLinus Torvalds return 0; 4481da177e4SLinus Torvalds } 44912f38872SAl Viro EXPORT_SYMBOL(simple_rmdir); 4501da177e4SLinus Torvalds 451*549c7297SChristian Brauner int simple_rename(struct user_namespace *mnt_userns, struct inode *old_dir, 452*549c7297SChristian Brauner struct dentry *old_dentry, struct inode *new_dir, 453*549c7297SChristian Brauner struct dentry *new_dentry, unsigned int flags) 4541da177e4SLinus Torvalds { 455dea655c2SDavid Howells struct inode *inode = d_inode(old_dentry); 456e36cb0b8SDavid Howells int they_are_dirs = d_is_dir(old_dentry); 4571da177e4SLinus Torvalds 458e0e0be8aSMiklos Szeredi if (flags & ~RENAME_NOREPLACE) 459e0e0be8aSMiklos Szeredi return -EINVAL; 460e0e0be8aSMiklos Szeredi 4611da177e4SLinus Torvalds if (!simple_empty(new_dentry)) 4621da177e4SLinus Torvalds return -ENOTEMPTY; 4631da177e4SLinus Torvalds 464dea655c2SDavid Howells if (d_really_is_positive(new_dentry)) { 4651da177e4SLinus Torvalds simple_unlink(new_dir, new_dentry); 466841590ceSAl Viro if (they_are_dirs) { 467dea655c2SDavid Howells drop_nlink(d_inode(new_dentry)); 4689a53c3a7SDave Hansen drop_nlink(old_dir); 469841590ceSAl Viro } 4701da177e4SLinus Torvalds } else if (they_are_dirs) { 4719a53c3a7SDave Hansen drop_nlink(old_dir); 472d8c76e6fSDave Hansen inc_nlink(new_dir); 4731da177e4SLinus Torvalds } 4741da177e4SLinus Torvalds 4751da177e4SLinus Torvalds old_dir->i_ctime = old_dir->i_mtime = new_dir->i_ctime = 476078cd827SDeepa Dinamani new_dir->i_mtime = inode->i_ctime = current_time(old_dir); 4771da177e4SLinus Torvalds 4781da177e4SLinus Torvalds return 0; 4791da177e4SLinus Torvalds } 48012f38872SAl Viro EXPORT_SYMBOL(simple_rename); 4811da177e4SLinus Torvalds 4827bb46a67Snpiggin@suse.de /** 483eef2380cSChristoph Hellwig * simple_setattr - setattr for simple filesystem 4847bb46a67Snpiggin@suse.de * @dentry: dentry 4857bb46a67Snpiggin@suse.de * @iattr: iattr structure 4867bb46a67Snpiggin@suse.de * 4877bb46a67Snpiggin@suse.de * Returns 0 on success, -error on failure. 4887bb46a67Snpiggin@suse.de * 489eef2380cSChristoph Hellwig * simple_setattr is a simple ->setattr implementation without a proper 490eef2380cSChristoph Hellwig * implementation of size changes. 491eef2380cSChristoph Hellwig * 492eef2380cSChristoph Hellwig * It can either be used for in-memory filesystems or special files 493eef2380cSChristoph Hellwig * on simple regular filesystems. Anything that needs to change on-disk 494eef2380cSChristoph Hellwig * or wire state on size changes needs its own setattr method. 4957bb46a67Snpiggin@suse.de */ 496*549c7297SChristian Brauner int simple_setattr(struct user_namespace *mnt_userns, struct dentry *dentry, 497*549c7297SChristian Brauner struct iattr *iattr) 4987bb46a67Snpiggin@suse.de { 499dea655c2SDavid Howells struct inode *inode = d_inode(dentry); 5007bb46a67Snpiggin@suse.de int error; 5017bb46a67Snpiggin@suse.de 502*549c7297SChristian Brauner error = setattr_prepare(mnt_userns, dentry, iattr); 5037bb46a67Snpiggin@suse.de if (error) 5047bb46a67Snpiggin@suse.de return error; 5057bb46a67Snpiggin@suse.de 5062c27c65eSChristoph Hellwig if (iattr->ia_valid & ATTR_SIZE) 5072c27c65eSChristoph Hellwig truncate_setsize(inode, iattr->ia_size); 508*549c7297SChristian Brauner setattr_copy(mnt_userns, inode, iattr); 509eef2380cSChristoph Hellwig mark_inode_dirty(inode); 510eef2380cSChristoph Hellwig return 0; 5117bb46a67Snpiggin@suse.de } 5127bb46a67Snpiggin@suse.de EXPORT_SYMBOL(simple_setattr); 5137bb46a67Snpiggin@suse.de 5141da177e4SLinus Torvalds int simple_readpage(struct file *file, struct page *page) 5151da177e4SLinus Torvalds { 516c0d92cbcSPekka J Enberg clear_highpage(page); 5171da177e4SLinus Torvalds flush_dcache_page(page); 5181da177e4SLinus Torvalds SetPageUptodate(page); 5191da177e4SLinus Torvalds unlock_page(page); 5201da177e4SLinus Torvalds return 0; 5211da177e4SLinus Torvalds } 52212f38872SAl Viro EXPORT_SYMBOL(simple_readpage); 5231da177e4SLinus Torvalds 524afddba49SNick Piggin int simple_write_begin(struct file *file, struct address_space *mapping, 525afddba49SNick Piggin loff_t pos, unsigned len, unsigned flags, 526afddba49SNick Piggin struct page **pagep, void **fsdata) 527afddba49SNick Piggin { 528afddba49SNick Piggin struct page *page; 529afddba49SNick Piggin pgoff_t index; 530afddba49SNick Piggin 53109cbfeafSKirill A. Shutemov index = pos >> PAGE_SHIFT; 532afddba49SNick Piggin 53354566b2cSNick Piggin page = grab_cache_page_write_begin(mapping, index, flags); 534afddba49SNick Piggin if (!page) 535afddba49SNick Piggin return -ENOMEM; 536afddba49SNick Piggin 537afddba49SNick Piggin *pagep = page; 538afddba49SNick Piggin 53909cbfeafSKirill A. Shutemov if (!PageUptodate(page) && (len != PAGE_SIZE)) { 54009cbfeafSKirill A. Shutemov unsigned from = pos & (PAGE_SIZE - 1); 541193cf4b9SBoaz Harrosh 54209cbfeafSKirill A. Shutemov zero_user_segments(page, 0, from, from + len, PAGE_SIZE); 543193cf4b9SBoaz Harrosh } 544193cf4b9SBoaz Harrosh return 0; 545afddba49SNick Piggin } 54612f38872SAl Viro EXPORT_SYMBOL(simple_write_begin); 547afddba49SNick Piggin 548ad2a722fSBoaz Harrosh /** 549ad2a722fSBoaz Harrosh * simple_write_end - .write_end helper for non-block-device FSes 5508e88bfbaSRandy Dunlap * @file: See .write_end of address_space_operations 551ad2a722fSBoaz Harrosh * @mapping: " 552ad2a722fSBoaz Harrosh * @pos: " 553ad2a722fSBoaz Harrosh * @len: " 554ad2a722fSBoaz Harrosh * @copied: " 555ad2a722fSBoaz Harrosh * @page: " 556ad2a722fSBoaz Harrosh * @fsdata: " 557ad2a722fSBoaz Harrosh * 558ad2a722fSBoaz Harrosh * simple_write_end does the minimum needed for updating a page after writing is 559ad2a722fSBoaz Harrosh * done. It has the same API signature as the .write_end of 560ad2a722fSBoaz Harrosh * address_space_operations vector. So it can just be set onto .write_end for 561ad2a722fSBoaz Harrosh * FSes that don't need any other processing. i_mutex is assumed to be held. 562ad2a722fSBoaz Harrosh * Block based filesystems should use generic_write_end(). 563ad2a722fSBoaz Harrosh * NOTE: Even though i_size might get updated by this function, mark_inode_dirty 564ad2a722fSBoaz Harrosh * is not called, so a filesystem that actually does store data in .write_inode 565ad2a722fSBoaz Harrosh * should extend on what's done here with a call to mark_inode_dirty() in the 566ad2a722fSBoaz Harrosh * case that i_size has changed. 56704fff641SAl Viro * 56804fff641SAl Viro * Use *ONLY* with simple_readpage() 569ad2a722fSBoaz Harrosh */ 570ad2a722fSBoaz Harrosh int simple_write_end(struct file *file, struct address_space *mapping, 571ad2a722fSBoaz Harrosh loff_t pos, unsigned len, unsigned copied, 572ad2a722fSBoaz Harrosh struct page *page, void *fsdata) 5731da177e4SLinus Torvalds { 5741da177e4SLinus Torvalds struct inode *inode = page->mapping->host; 575ad2a722fSBoaz Harrosh loff_t last_pos = pos + copied; 576ad2a722fSBoaz Harrosh 577ad2a722fSBoaz Harrosh /* zero the stale part of the page if we did a short copy */ 57804fff641SAl Viro if (!PageUptodate(page)) { 579ad2a722fSBoaz Harrosh if (copied < len) { 58009cbfeafSKirill A. Shutemov unsigned from = pos & (PAGE_SIZE - 1); 581ad2a722fSBoaz Harrosh 582ad2a722fSBoaz Harrosh zero_user(page, from + copied, len - copied); 583ad2a722fSBoaz Harrosh } 584955eff5aSNick Piggin SetPageUptodate(page); 58504fff641SAl Viro } 5861da177e4SLinus Torvalds /* 5871da177e4SLinus Torvalds * No need to use i_size_read() here, the i_size 5881b1dcc1bSJes Sorensen * cannot change under us because we hold the i_mutex. 5891da177e4SLinus Torvalds */ 590ad2a722fSBoaz Harrosh if (last_pos > inode->i_size) 591ad2a722fSBoaz Harrosh i_size_write(inode, last_pos); 592ad2a722fSBoaz Harrosh 5931da177e4SLinus Torvalds set_page_dirty(page); 594afddba49SNick Piggin unlock_page(page); 59509cbfeafSKirill A. Shutemov put_page(page); 596afddba49SNick Piggin 597afddba49SNick Piggin return copied; 598afddba49SNick Piggin } 59912f38872SAl Viro EXPORT_SYMBOL(simple_write_end); 600afddba49SNick Piggin 6011a1c9bb4SJeff Layton /* 6021a1c9bb4SJeff Layton * the inodes created here are not hashed. If you use iunique to generate 6031a1c9bb4SJeff Layton * unique inode values later for this filesystem, then you must take care 6041a1c9bb4SJeff Layton * to pass it an appropriate max_reserved value to avoid collisions. 6051a1c9bb4SJeff Layton */ 6067d683a09SRoberto Sassu int simple_fill_super(struct super_block *s, unsigned long magic, 607cda37124SEric Biggers const struct tree_descr *files) 6081da177e4SLinus Torvalds { 6091da177e4SLinus Torvalds struct inode *inode; 6101da177e4SLinus Torvalds struct dentry *root; 6111da177e4SLinus Torvalds struct dentry *dentry; 6121da177e4SLinus Torvalds int i; 6131da177e4SLinus Torvalds 61409cbfeafSKirill A. Shutemov s->s_blocksize = PAGE_SIZE; 61509cbfeafSKirill A. Shutemov s->s_blocksize_bits = PAGE_SHIFT; 6161da177e4SLinus Torvalds s->s_magic = magic; 617759b9775SHugh Dickins s->s_op = &simple_super_operations; 6181da177e4SLinus Torvalds s->s_time_gran = 1; 6191da177e4SLinus Torvalds 6201da177e4SLinus Torvalds inode = new_inode(s); 6211da177e4SLinus Torvalds if (!inode) 6221da177e4SLinus Torvalds return -ENOMEM; 6231a1c9bb4SJeff Layton /* 6241a1c9bb4SJeff Layton * because the root inode is 1, the files array must not contain an 6251a1c9bb4SJeff Layton * entry at index 1 6261a1c9bb4SJeff Layton */ 6271a1c9bb4SJeff Layton inode->i_ino = 1; 6281da177e4SLinus Torvalds inode->i_mode = S_IFDIR | 0755; 629078cd827SDeepa Dinamani inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode); 6301da177e4SLinus Torvalds inode->i_op = &simple_dir_inode_operations; 6311da177e4SLinus Torvalds inode->i_fop = &simple_dir_operations; 632bfe86848SMiklos Szeredi set_nlink(inode, 2); 63348fde701SAl Viro root = d_make_root(inode); 63448fde701SAl Viro if (!root) 6351da177e4SLinus Torvalds return -ENOMEM; 6361da177e4SLinus Torvalds for (i = 0; !files->name || files->name[0]; i++, files++) { 6371da177e4SLinus Torvalds if (!files->name) 6381da177e4SLinus Torvalds continue; 6391a1c9bb4SJeff Layton 6401a1c9bb4SJeff Layton /* warn if it tries to conflict with the root inode */ 6411a1c9bb4SJeff Layton if (unlikely(i == 1)) 6421a1c9bb4SJeff Layton printk(KERN_WARNING "%s: %s passed in a files array" 6431a1c9bb4SJeff Layton "with an index of 1!\n", __func__, 6441a1c9bb4SJeff Layton s->s_type->name); 6451a1c9bb4SJeff Layton 6461da177e4SLinus Torvalds dentry = d_alloc_name(root, files->name); 6471da177e4SLinus Torvalds if (!dentry) 6481da177e4SLinus Torvalds goto out; 6491da177e4SLinus Torvalds inode = new_inode(s); 65032096ea1SKonstantin Khlebnikov if (!inode) { 65132096ea1SKonstantin Khlebnikov dput(dentry); 6521da177e4SLinus Torvalds goto out; 65332096ea1SKonstantin Khlebnikov } 6541da177e4SLinus Torvalds inode->i_mode = S_IFREG | files->mode; 655078cd827SDeepa Dinamani inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode); 6561da177e4SLinus Torvalds inode->i_fop = files->ops; 6571da177e4SLinus Torvalds inode->i_ino = i; 6581da177e4SLinus Torvalds d_add(dentry, inode); 6591da177e4SLinus Torvalds } 6601da177e4SLinus Torvalds s->s_root = root; 6611da177e4SLinus Torvalds return 0; 6621da177e4SLinus Torvalds out: 6631da177e4SLinus Torvalds d_genocide(root); 664640946f2SAl Viro shrink_dcache_parent(root); 6651da177e4SLinus Torvalds dput(root); 6661da177e4SLinus Torvalds return -ENOMEM; 6671da177e4SLinus Torvalds } 66812f38872SAl Viro EXPORT_SYMBOL(simple_fill_super); 6691da177e4SLinus Torvalds 6701da177e4SLinus Torvalds static DEFINE_SPINLOCK(pin_fs_lock); 6711da177e4SLinus Torvalds 6721f5ce9e9STrond Myklebust int simple_pin_fs(struct file_system_type *type, struct vfsmount **mount, int *count) 6731da177e4SLinus Torvalds { 6741da177e4SLinus Torvalds struct vfsmount *mnt = NULL; 6751da177e4SLinus Torvalds spin_lock(&pin_fs_lock); 6761da177e4SLinus Torvalds if (unlikely(!*mount)) { 6771da177e4SLinus Torvalds spin_unlock(&pin_fs_lock); 6781751e8a6SLinus Torvalds mnt = vfs_kern_mount(type, SB_KERNMOUNT, type->name, NULL); 6791da177e4SLinus Torvalds if (IS_ERR(mnt)) 6801da177e4SLinus Torvalds return PTR_ERR(mnt); 6811da177e4SLinus Torvalds spin_lock(&pin_fs_lock); 6821da177e4SLinus Torvalds if (!*mount) 6831da177e4SLinus Torvalds *mount = mnt; 6841da177e4SLinus Torvalds } 6851da177e4SLinus Torvalds mntget(*mount); 6861da177e4SLinus Torvalds ++*count; 6871da177e4SLinus Torvalds spin_unlock(&pin_fs_lock); 6881da177e4SLinus Torvalds mntput(mnt); 6891da177e4SLinus Torvalds return 0; 6901da177e4SLinus Torvalds } 69112f38872SAl Viro EXPORT_SYMBOL(simple_pin_fs); 6921da177e4SLinus Torvalds 6931da177e4SLinus Torvalds void simple_release_fs(struct vfsmount **mount, int *count) 6941da177e4SLinus Torvalds { 6951da177e4SLinus Torvalds struct vfsmount *mnt; 6961da177e4SLinus Torvalds spin_lock(&pin_fs_lock); 6971da177e4SLinus Torvalds mnt = *mount; 6981da177e4SLinus Torvalds if (!--*count) 6991da177e4SLinus Torvalds *mount = NULL; 7001da177e4SLinus Torvalds spin_unlock(&pin_fs_lock); 7011da177e4SLinus Torvalds mntput(mnt); 7021da177e4SLinus Torvalds } 70312f38872SAl Viro EXPORT_SYMBOL(simple_release_fs); 7041da177e4SLinus Torvalds 7056d1029b5SAkinobu Mita /** 7066d1029b5SAkinobu Mita * simple_read_from_buffer - copy data from the buffer to user space 7076d1029b5SAkinobu Mita * @to: the user space buffer to read to 7086d1029b5SAkinobu Mita * @count: the maximum number of bytes to read 7096d1029b5SAkinobu Mita * @ppos: the current position in the buffer 7106d1029b5SAkinobu Mita * @from: the buffer to read from 7116d1029b5SAkinobu Mita * @available: the size of the buffer 7126d1029b5SAkinobu Mita * 7136d1029b5SAkinobu Mita * The simple_read_from_buffer() function reads up to @count bytes from the 7146d1029b5SAkinobu Mita * buffer @from at offset @ppos into the user space address starting at @to. 7156d1029b5SAkinobu Mita * 7166d1029b5SAkinobu Mita * On success, the number of bytes read is returned and the offset @ppos is 7176d1029b5SAkinobu Mita * advanced by this number, or negative value is returned on error. 7186d1029b5SAkinobu Mita **/ 7191da177e4SLinus Torvalds ssize_t simple_read_from_buffer(void __user *to, size_t count, loff_t *ppos, 7201da177e4SLinus Torvalds const void *from, size_t available) 7211da177e4SLinus Torvalds { 7221da177e4SLinus Torvalds loff_t pos = *ppos; 72314be2746SSteven Rostedt size_t ret; 72414be2746SSteven Rostedt 7251da177e4SLinus Torvalds if (pos < 0) 7261da177e4SLinus Torvalds return -EINVAL; 72714be2746SSteven Rostedt if (pos >= available || !count) 7281da177e4SLinus Torvalds return 0; 7291da177e4SLinus Torvalds if (count > available - pos) 7301da177e4SLinus Torvalds count = available - pos; 73114be2746SSteven Rostedt ret = copy_to_user(to, from + pos, count); 73214be2746SSteven Rostedt if (ret == count) 7331da177e4SLinus Torvalds return -EFAULT; 73414be2746SSteven Rostedt count -= ret; 7351da177e4SLinus Torvalds *ppos = pos + count; 7361da177e4SLinus Torvalds return count; 7371da177e4SLinus Torvalds } 73812f38872SAl Viro EXPORT_SYMBOL(simple_read_from_buffer); 7391da177e4SLinus Torvalds 7406d1029b5SAkinobu Mita /** 7416a727b43SJiri Slaby * simple_write_to_buffer - copy data from user space to the buffer 7426a727b43SJiri Slaby * @to: the buffer to write to 7436a727b43SJiri Slaby * @available: the size of the buffer 7446a727b43SJiri Slaby * @ppos: the current position in the buffer 7456a727b43SJiri Slaby * @from: the user space buffer to read from 7466a727b43SJiri Slaby * @count: the maximum number of bytes to read 7476a727b43SJiri Slaby * 7486a727b43SJiri Slaby * The simple_write_to_buffer() function reads up to @count bytes from the user 7496a727b43SJiri Slaby * space address starting at @from into the buffer @to at offset @ppos. 7506a727b43SJiri Slaby * 7516a727b43SJiri Slaby * On success, the number of bytes written is returned and the offset @ppos is 7526a727b43SJiri Slaby * advanced by this number, or negative value is returned on error. 7536a727b43SJiri Slaby **/ 7546a727b43SJiri Slaby ssize_t simple_write_to_buffer(void *to, size_t available, loff_t *ppos, 7556a727b43SJiri Slaby const void __user *from, size_t count) 7566a727b43SJiri Slaby { 7576a727b43SJiri Slaby loff_t pos = *ppos; 7586a727b43SJiri Slaby size_t res; 7596a727b43SJiri Slaby 7606a727b43SJiri Slaby if (pos < 0) 7616a727b43SJiri Slaby return -EINVAL; 7626a727b43SJiri Slaby if (pos >= available || !count) 7636a727b43SJiri Slaby return 0; 7646a727b43SJiri Slaby if (count > available - pos) 7656a727b43SJiri Slaby count = available - pos; 7666a727b43SJiri Slaby res = copy_from_user(to + pos, from, count); 7676a727b43SJiri Slaby if (res == count) 7686a727b43SJiri Slaby return -EFAULT; 7696a727b43SJiri Slaby count -= res; 7706a727b43SJiri Slaby *ppos = pos + count; 7716a727b43SJiri Slaby return count; 7726a727b43SJiri Slaby } 77312f38872SAl Viro EXPORT_SYMBOL(simple_write_to_buffer); 7746a727b43SJiri Slaby 7756a727b43SJiri Slaby /** 7766d1029b5SAkinobu Mita * memory_read_from_buffer - copy data from the buffer 7776d1029b5SAkinobu Mita * @to: the kernel space buffer to read to 7786d1029b5SAkinobu Mita * @count: the maximum number of bytes to read 7796d1029b5SAkinobu Mita * @ppos: the current position in the buffer 7806d1029b5SAkinobu Mita * @from: the buffer to read from 7816d1029b5SAkinobu Mita * @available: the size of the buffer 7826d1029b5SAkinobu Mita * 7836d1029b5SAkinobu Mita * The memory_read_from_buffer() function reads up to @count bytes from the 7846d1029b5SAkinobu Mita * buffer @from at offset @ppos into the kernel space address starting at @to. 7856d1029b5SAkinobu Mita * 7866d1029b5SAkinobu Mita * On success, the number of bytes read is returned and the offset @ppos is 7876d1029b5SAkinobu Mita * advanced by this number, or negative value is returned on error. 7886d1029b5SAkinobu Mita **/ 78993b07113SAkinobu Mita ssize_t memory_read_from_buffer(void *to, size_t count, loff_t *ppos, 79093b07113SAkinobu Mita const void *from, size_t available) 79193b07113SAkinobu Mita { 79293b07113SAkinobu Mita loff_t pos = *ppos; 79393b07113SAkinobu Mita 79493b07113SAkinobu Mita if (pos < 0) 79593b07113SAkinobu Mita return -EINVAL; 79693b07113SAkinobu Mita if (pos >= available) 79793b07113SAkinobu Mita return 0; 79893b07113SAkinobu Mita if (count > available - pos) 79993b07113SAkinobu Mita count = available - pos; 80093b07113SAkinobu Mita memcpy(to, from + pos, count); 80193b07113SAkinobu Mita *ppos = pos + count; 80293b07113SAkinobu Mita 80393b07113SAkinobu Mita return count; 80493b07113SAkinobu Mita } 80512f38872SAl Viro EXPORT_SYMBOL(memory_read_from_buffer); 80693b07113SAkinobu Mita 8071da177e4SLinus Torvalds /* 8081da177e4SLinus Torvalds * Transaction based IO. 8091da177e4SLinus Torvalds * The file expects a single write which triggers the transaction, and then 8101da177e4SLinus Torvalds * possibly a read which collects the result - which is stored in a 8111da177e4SLinus Torvalds * file-local buffer. 8121da177e4SLinus Torvalds */ 81376791ab2SIngo Molnar 81476791ab2SIngo Molnar void simple_transaction_set(struct file *file, size_t n) 81576791ab2SIngo Molnar { 81676791ab2SIngo Molnar struct simple_transaction_argresp *ar = file->private_data; 81776791ab2SIngo Molnar 81876791ab2SIngo Molnar BUG_ON(n > SIMPLE_TRANSACTION_LIMIT); 81976791ab2SIngo Molnar 82076791ab2SIngo Molnar /* 82176791ab2SIngo Molnar * The barrier ensures that ar->size will really remain zero until 82276791ab2SIngo Molnar * ar->data is ready for reading. 82376791ab2SIngo Molnar */ 82476791ab2SIngo Molnar smp_mb(); 82576791ab2SIngo Molnar ar->size = n; 82676791ab2SIngo Molnar } 82712f38872SAl Viro EXPORT_SYMBOL(simple_transaction_set); 82876791ab2SIngo Molnar 8291da177e4SLinus Torvalds char *simple_transaction_get(struct file *file, const char __user *buf, size_t size) 8301da177e4SLinus Torvalds { 8311da177e4SLinus Torvalds struct simple_transaction_argresp *ar; 8321da177e4SLinus Torvalds static DEFINE_SPINLOCK(simple_transaction_lock); 8331da177e4SLinus Torvalds 8341da177e4SLinus Torvalds if (size > SIMPLE_TRANSACTION_LIMIT - 1) 8351da177e4SLinus Torvalds return ERR_PTR(-EFBIG); 8361da177e4SLinus Torvalds 8371da177e4SLinus Torvalds ar = (struct simple_transaction_argresp *)get_zeroed_page(GFP_KERNEL); 8381da177e4SLinus Torvalds if (!ar) 8391da177e4SLinus Torvalds return ERR_PTR(-ENOMEM); 8401da177e4SLinus Torvalds 8411da177e4SLinus Torvalds spin_lock(&simple_transaction_lock); 8421da177e4SLinus Torvalds 8431da177e4SLinus Torvalds /* only one write allowed per open */ 8441da177e4SLinus Torvalds if (file->private_data) { 8451da177e4SLinus Torvalds spin_unlock(&simple_transaction_lock); 8461da177e4SLinus Torvalds free_page((unsigned long)ar); 8471da177e4SLinus Torvalds return ERR_PTR(-EBUSY); 8481da177e4SLinus Torvalds } 8491da177e4SLinus Torvalds 8501da177e4SLinus Torvalds file->private_data = ar; 8511da177e4SLinus Torvalds 8521da177e4SLinus Torvalds spin_unlock(&simple_transaction_lock); 8531da177e4SLinus Torvalds 8541da177e4SLinus Torvalds if (copy_from_user(ar->data, buf, size)) 8551da177e4SLinus Torvalds return ERR_PTR(-EFAULT); 8561da177e4SLinus Torvalds 8571da177e4SLinus Torvalds return ar->data; 8581da177e4SLinus Torvalds } 85912f38872SAl Viro EXPORT_SYMBOL(simple_transaction_get); 8601da177e4SLinus Torvalds 8611da177e4SLinus Torvalds ssize_t simple_transaction_read(struct file *file, char __user *buf, size_t size, loff_t *pos) 8621da177e4SLinus Torvalds { 8631da177e4SLinus Torvalds struct simple_transaction_argresp *ar = file->private_data; 8641da177e4SLinus Torvalds 8651da177e4SLinus Torvalds if (!ar) 8661da177e4SLinus Torvalds return 0; 8671da177e4SLinus Torvalds return simple_read_from_buffer(buf, size, pos, ar->data, ar->size); 8681da177e4SLinus Torvalds } 86912f38872SAl Viro EXPORT_SYMBOL(simple_transaction_read); 8701da177e4SLinus Torvalds 8711da177e4SLinus Torvalds int simple_transaction_release(struct inode *inode, struct file *file) 8721da177e4SLinus Torvalds { 8731da177e4SLinus Torvalds free_page((unsigned long)file->private_data); 8741da177e4SLinus Torvalds return 0; 8751da177e4SLinus Torvalds } 87612f38872SAl Viro EXPORT_SYMBOL(simple_transaction_release); 8771da177e4SLinus Torvalds 878acaefc25SArnd Bergmann /* Simple attribute files */ 879acaefc25SArnd Bergmann 880acaefc25SArnd Bergmann struct simple_attr { 8818b88b099SChristoph Hellwig int (*get)(void *, u64 *); 8828b88b099SChristoph Hellwig int (*set)(void *, u64); 883acaefc25SArnd Bergmann char get_buf[24]; /* enough to store a u64 and "\n\0" */ 884acaefc25SArnd Bergmann char set_buf[24]; 885acaefc25SArnd Bergmann void *data; 886acaefc25SArnd Bergmann const char *fmt; /* format for read operation */ 8877cf34c76SIngo Molnar struct mutex mutex; /* protects access to these buffers */ 888acaefc25SArnd Bergmann }; 889acaefc25SArnd Bergmann 890acaefc25SArnd Bergmann /* simple_attr_open is called by an actual attribute open file operation 891acaefc25SArnd Bergmann * to set the attribute specific access operations. */ 892acaefc25SArnd Bergmann int simple_attr_open(struct inode *inode, struct file *file, 8938b88b099SChristoph Hellwig int (*get)(void *, u64 *), int (*set)(void *, u64), 894acaefc25SArnd Bergmann const char *fmt) 895acaefc25SArnd Bergmann { 896acaefc25SArnd Bergmann struct simple_attr *attr; 897acaefc25SArnd Bergmann 898a65cab7dSEric Biggers attr = kzalloc(sizeof(*attr), GFP_KERNEL); 899acaefc25SArnd Bergmann if (!attr) 900acaefc25SArnd Bergmann return -ENOMEM; 901acaefc25SArnd Bergmann 902acaefc25SArnd Bergmann attr->get = get; 903acaefc25SArnd Bergmann attr->set = set; 9048e18e294STheodore Ts'o attr->data = inode->i_private; 905acaefc25SArnd Bergmann attr->fmt = fmt; 9067cf34c76SIngo Molnar mutex_init(&attr->mutex); 907acaefc25SArnd Bergmann 908acaefc25SArnd Bergmann file->private_data = attr; 909acaefc25SArnd Bergmann 910acaefc25SArnd Bergmann return nonseekable_open(inode, file); 911acaefc25SArnd Bergmann } 91212f38872SAl Viro EXPORT_SYMBOL_GPL(simple_attr_open); 913acaefc25SArnd Bergmann 91474bedc4dSChristoph Hellwig int simple_attr_release(struct inode *inode, struct file *file) 915acaefc25SArnd Bergmann { 916acaefc25SArnd Bergmann kfree(file->private_data); 917acaefc25SArnd Bergmann return 0; 918acaefc25SArnd Bergmann } 91912f38872SAl Viro EXPORT_SYMBOL_GPL(simple_attr_release); /* GPL-only? This? Really? */ 920acaefc25SArnd Bergmann 921acaefc25SArnd Bergmann /* read from the buffer that is filled with the get function */ 922acaefc25SArnd Bergmann ssize_t simple_attr_read(struct file *file, char __user *buf, 923acaefc25SArnd Bergmann size_t len, loff_t *ppos) 924acaefc25SArnd Bergmann { 925acaefc25SArnd Bergmann struct simple_attr *attr; 926acaefc25SArnd Bergmann size_t size; 927acaefc25SArnd Bergmann ssize_t ret; 928acaefc25SArnd Bergmann 929acaefc25SArnd Bergmann attr = file->private_data; 930acaefc25SArnd Bergmann 931acaefc25SArnd Bergmann if (!attr->get) 932acaefc25SArnd Bergmann return -EACCES; 933acaefc25SArnd Bergmann 9349261303aSChristoph Hellwig ret = mutex_lock_interruptible(&attr->mutex); 9359261303aSChristoph Hellwig if (ret) 9369261303aSChristoph Hellwig return ret; 9379261303aSChristoph Hellwig 938a65cab7dSEric Biggers if (*ppos && attr->get_buf[0]) { 939a65cab7dSEric Biggers /* continued read */ 940acaefc25SArnd Bergmann size = strlen(attr->get_buf); 941a65cab7dSEric Biggers } else { 942a65cab7dSEric Biggers /* first read */ 9438b88b099SChristoph Hellwig u64 val; 9448b88b099SChristoph Hellwig ret = attr->get(attr->data, &val); 9458b88b099SChristoph Hellwig if (ret) 9468b88b099SChristoph Hellwig goto out; 9478b88b099SChristoph Hellwig 948acaefc25SArnd Bergmann size = scnprintf(attr->get_buf, sizeof(attr->get_buf), 9498b88b099SChristoph Hellwig attr->fmt, (unsigned long long)val); 9508b88b099SChristoph Hellwig } 951acaefc25SArnd Bergmann 952acaefc25SArnd Bergmann ret = simple_read_from_buffer(buf, len, ppos, attr->get_buf, size); 9538b88b099SChristoph Hellwig out: 9547cf34c76SIngo Molnar mutex_unlock(&attr->mutex); 955acaefc25SArnd Bergmann return ret; 956acaefc25SArnd Bergmann } 95712f38872SAl Viro EXPORT_SYMBOL_GPL(simple_attr_read); 958acaefc25SArnd Bergmann 959acaefc25SArnd Bergmann /* interpret the buffer as a number to call the set function with */ 960acaefc25SArnd Bergmann ssize_t simple_attr_write(struct file *file, const char __user *buf, 961acaefc25SArnd Bergmann size_t len, loff_t *ppos) 962acaefc25SArnd Bergmann { 963acaefc25SArnd Bergmann struct simple_attr *attr; 964488dac0cSYicong Yang unsigned long long val; 965acaefc25SArnd Bergmann size_t size; 966acaefc25SArnd Bergmann ssize_t ret; 967acaefc25SArnd Bergmann 968acaefc25SArnd Bergmann attr = file->private_data; 969acaefc25SArnd Bergmann if (!attr->set) 970acaefc25SArnd Bergmann return -EACCES; 971acaefc25SArnd Bergmann 9729261303aSChristoph Hellwig ret = mutex_lock_interruptible(&attr->mutex); 9739261303aSChristoph Hellwig if (ret) 9749261303aSChristoph Hellwig return ret; 9759261303aSChristoph Hellwig 976acaefc25SArnd Bergmann ret = -EFAULT; 977acaefc25SArnd Bergmann size = min(sizeof(attr->set_buf) - 1, len); 978acaefc25SArnd Bergmann if (copy_from_user(attr->set_buf, buf, size)) 979acaefc25SArnd Bergmann goto out; 980acaefc25SArnd Bergmann 981acaefc25SArnd Bergmann attr->set_buf[size] = '\0'; 982488dac0cSYicong Yang ret = kstrtoull(attr->set_buf, 0, &val); 983488dac0cSYicong Yang if (ret) 984488dac0cSYicong Yang goto out; 98505cc0ceeSWu Fengguang ret = attr->set(attr->data, val); 98605cc0ceeSWu Fengguang if (ret == 0) 98705cc0ceeSWu Fengguang ret = len; /* on success, claim we got the whole input */ 988acaefc25SArnd Bergmann out: 9897cf34c76SIngo Molnar mutex_unlock(&attr->mutex); 990acaefc25SArnd Bergmann return ret; 991acaefc25SArnd Bergmann } 99212f38872SAl Viro EXPORT_SYMBOL_GPL(simple_attr_write); 993acaefc25SArnd Bergmann 9942596110aSChristoph Hellwig /** 9952596110aSChristoph Hellwig * generic_fh_to_dentry - generic helper for the fh_to_dentry export operation 9962596110aSChristoph Hellwig * @sb: filesystem to do the file handle conversion on 9972596110aSChristoph Hellwig * @fid: file handle to convert 9982596110aSChristoph Hellwig * @fh_len: length of the file handle in bytes 9992596110aSChristoph Hellwig * @fh_type: type of file handle 10002596110aSChristoph Hellwig * @get_inode: filesystem callback to retrieve inode 10012596110aSChristoph Hellwig * 10022596110aSChristoph Hellwig * This function decodes @fid as long as it has one of the well-known 10032596110aSChristoph Hellwig * Linux filehandle types and calls @get_inode on it to retrieve the 10042596110aSChristoph Hellwig * inode for the object specified in the file handle. 10052596110aSChristoph Hellwig */ 10062596110aSChristoph Hellwig struct dentry *generic_fh_to_dentry(struct super_block *sb, struct fid *fid, 10072596110aSChristoph Hellwig int fh_len, int fh_type, struct inode *(*get_inode) 10082596110aSChristoph Hellwig (struct super_block *sb, u64 ino, u32 gen)) 10092596110aSChristoph Hellwig { 10102596110aSChristoph Hellwig struct inode *inode = NULL; 10112596110aSChristoph Hellwig 10122596110aSChristoph Hellwig if (fh_len < 2) 10132596110aSChristoph Hellwig return NULL; 10142596110aSChristoph Hellwig 10152596110aSChristoph Hellwig switch (fh_type) { 10162596110aSChristoph Hellwig case FILEID_INO32_GEN: 10172596110aSChristoph Hellwig case FILEID_INO32_GEN_PARENT: 10182596110aSChristoph Hellwig inode = get_inode(sb, fid->i32.ino, fid->i32.gen); 10192596110aSChristoph Hellwig break; 10202596110aSChristoph Hellwig } 10212596110aSChristoph Hellwig 10224ea3ada2SChristoph Hellwig return d_obtain_alias(inode); 10232596110aSChristoph Hellwig } 10242596110aSChristoph Hellwig EXPORT_SYMBOL_GPL(generic_fh_to_dentry); 10252596110aSChristoph Hellwig 10262596110aSChristoph Hellwig /** 1027ca186830SYanchuan Nian * generic_fh_to_parent - generic helper for the fh_to_parent export operation 10282596110aSChristoph Hellwig * @sb: filesystem to do the file handle conversion on 10292596110aSChristoph Hellwig * @fid: file handle to convert 10302596110aSChristoph Hellwig * @fh_len: length of the file handle in bytes 10312596110aSChristoph Hellwig * @fh_type: type of file handle 10322596110aSChristoph Hellwig * @get_inode: filesystem callback to retrieve inode 10332596110aSChristoph Hellwig * 10342596110aSChristoph Hellwig * This function decodes @fid as long as it has one of the well-known 10352596110aSChristoph Hellwig * Linux filehandle types and calls @get_inode on it to retrieve the 10362596110aSChristoph Hellwig * inode for the _parent_ object specified in the file handle if it 10372596110aSChristoph Hellwig * is specified in the file handle, or NULL otherwise. 10382596110aSChristoph Hellwig */ 10392596110aSChristoph Hellwig struct dentry *generic_fh_to_parent(struct super_block *sb, struct fid *fid, 10402596110aSChristoph Hellwig int fh_len, int fh_type, struct inode *(*get_inode) 10412596110aSChristoph Hellwig (struct super_block *sb, u64 ino, u32 gen)) 10422596110aSChristoph Hellwig { 10432596110aSChristoph Hellwig struct inode *inode = NULL; 10442596110aSChristoph Hellwig 10452596110aSChristoph Hellwig if (fh_len <= 2) 10462596110aSChristoph Hellwig return NULL; 10472596110aSChristoph Hellwig 10482596110aSChristoph Hellwig switch (fh_type) { 10492596110aSChristoph Hellwig case FILEID_INO32_GEN_PARENT: 10502596110aSChristoph Hellwig inode = get_inode(sb, fid->i32.parent_ino, 10512596110aSChristoph Hellwig (fh_len > 3 ? fid->i32.parent_gen : 0)); 10522596110aSChristoph Hellwig break; 10532596110aSChristoph Hellwig } 10542596110aSChristoph Hellwig 10554ea3ada2SChristoph Hellwig return d_obtain_alias(inode); 10562596110aSChristoph Hellwig } 10572596110aSChristoph Hellwig EXPORT_SYMBOL_GPL(generic_fh_to_parent); 10582596110aSChristoph Hellwig 10591b061d92SChristoph Hellwig /** 1060ac13a829SFabian Frederick * __generic_file_fsync - generic fsync implementation for simple filesystems 1061ac13a829SFabian Frederick * 10621b061d92SChristoph Hellwig * @file: file to synchronize 1063ac13a829SFabian Frederick * @start: start offset in bytes 1064ac13a829SFabian Frederick * @end: end offset in bytes (inclusive) 10651b061d92SChristoph Hellwig * @datasync: only synchronize essential metadata if true 10661b061d92SChristoph Hellwig * 10671b061d92SChristoph Hellwig * This is a generic implementation of the fsync method for simple 10681b061d92SChristoph Hellwig * filesystems which track all non-inode metadata in the buffers list 10691b061d92SChristoph Hellwig * hanging off the address_space structure. 10701b061d92SChristoph Hellwig */ 1071ac13a829SFabian Frederick int __generic_file_fsync(struct file *file, loff_t start, loff_t end, 107202c24a82SJosef Bacik int datasync) 1073d5aacad5SAl Viro { 10747ea80859SChristoph Hellwig struct inode *inode = file->f_mapping->host; 1075d5aacad5SAl Viro int err; 1076d5aacad5SAl Viro int ret; 1077d5aacad5SAl Viro 1078383aa543SJeff Layton err = file_write_and_wait_range(file, start, end); 107902c24a82SJosef Bacik if (err) 108002c24a82SJosef Bacik return err; 108102c24a82SJosef Bacik 10825955102cSAl Viro inode_lock(inode); 1083d5aacad5SAl Viro ret = sync_mapping_buffers(inode->i_mapping); 10840ae45f63STheodore Ts'o if (!(inode->i_state & I_DIRTY_ALL)) 108502c24a82SJosef Bacik goto out; 1086d5aacad5SAl Viro if (datasync && !(inode->i_state & I_DIRTY_DATASYNC)) 108702c24a82SJosef Bacik goto out; 1088d5aacad5SAl Viro 1089c3765016SChristoph Hellwig err = sync_inode_metadata(inode, 1); 1090d5aacad5SAl Viro if (ret == 0) 1091d5aacad5SAl Viro ret = err; 1092ac13a829SFabian Frederick 109302c24a82SJosef Bacik out: 10945955102cSAl Viro inode_unlock(inode); 1095383aa543SJeff Layton /* check and advance again to catch errors after syncing out buffers */ 1096383aa543SJeff Layton err = file_check_and_advance_wb_err(file); 1097383aa543SJeff Layton if (ret == 0) 1098383aa543SJeff Layton ret = err; 1099383aa543SJeff Layton return ret; 1100d5aacad5SAl Viro } 1101ac13a829SFabian Frederick EXPORT_SYMBOL(__generic_file_fsync); 1102ac13a829SFabian Frederick 1103ac13a829SFabian Frederick /** 1104ac13a829SFabian Frederick * generic_file_fsync - generic fsync implementation for simple filesystems 1105ac13a829SFabian Frederick * with flush 1106ac13a829SFabian Frederick * @file: file to synchronize 1107ac13a829SFabian Frederick * @start: start offset in bytes 1108ac13a829SFabian Frederick * @end: end offset in bytes (inclusive) 1109ac13a829SFabian Frederick * @datasync: only synchronize essential metadata if true 1110ac13a829SFabian Frederick * 1111ac13a829SFabian Frederick */ 1112ac13a829SFabian Frederick 1113ac13a829SFabian Frederick int generic_file_fsync(struct file *file, loff_t start, loff_t end, 1114ac13a829SFabian Frederick int datasync) 1115ac13a829SFabian Frederick { 1116ac13a829SFabian Frederick struct inode *inode = file->f_mapping->host; 1117ac13a829SFabian Frederick int err; 1118ac13a829SFabian Frederick 1119ac13a829SFabian Frederick err = __generic_file_fsync(file, start, end, datasync); 1120ac13a829SFabian Frederick if (err) 1121ac13a829SFabian Frederick return err; 11229398554fSChristoph Hellwig return blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL); 1123ac13a829SFabian Frederick } 11241b061d92SChristoph Hellwig EXPORT_SYMBOL(generic_file_fsync); 11251b061d92SChristoph Hellwig 112630ca22c7SPatrick J. LoPresti /** 112730ca22c7SPatrick J. LoPresti * generic_check_addressable - Check addressability of file system 112830ca22c7SPatrick J. LoPresti * @blocksize_bits: log of file system block size 112930ca22c7SPatrick J. LoPresti * @num_blocks: number of blocks in file system 113030ca22c7SPatrick J. LoPresti * 113130ca22c7SPatrick J. LoPresti * Determine whether a file system with @num_blocks blocks (and a 113230ca22c7SPatrick J. LoPresti * block size of 2**@blocksize_bits) is addressable by the sector_t 113330ca22c7SPatrick J. LoPresti * and page cache of the system. Return 0 if so and -EFBIG otherwise. 113430ca22c7SPatrick J. LoPresti */ 113530ca22c7SPatrick J. LoPresti int generic_check_addressable(unsigned blocksize_bits, u64 num_blocks) 113630ca22c7SPatrick J. LoPresti { 113730ca22c7SPatrick J. LoPresti u64 last_fs_block = num_blocks - 1; 1138a33f13efSJoel Becker u64 last_fs_page = 113909cbfeafSKirill A. Shutemov last_fs_block >> (PAGE_SHIFT - blocksize_bits); 114030ca22c7SPatrick J. LoPresti 114130ca22c7SPatrick J. LoPresti if (unlikely(num_blocks == 0)) 114230ca22c7SPatrick J. LoPresti return 0; 114330ca22c7SPatrick J. LoPresti 114409cbfeafSKirill A. Shutemov if ((blocksize_bits < 9) || (blocksize_bits > PAGE_SHIFT)) 114530ca22c7SPatrick J. LoPresti return -EINVAL; 114630ca22c7SPatrick J. LoPresti 1147a33f13efSJoel Becker if ((last_fs_block > (sector_t)(~0ULL) >> (blocksize_bits - 9)) || 1148a33f13efSJoel Becker (last_fs_page > (pgoff_t)(~0ULL))) { 114930ca22c7SPatrick J. LoPresti return -EFBIG; 115030ca22c7SPatrick J. LoPresti } 115130ca22c7SPatrick J. LoPresti return 0; 115230ca22c7SPatrick J. LoPresti } 115330ca22c7SPatrick J. LoPresti EXPORT_SYMBOL(generic_check_addressable); 115430ca22c7SPatrick J. LoPresti 11551b061d92SChristoph Hellwig /* 11561b061d92SChristoph Hellwig * No-op implementation of ->fsync for in-memory filesystems. 11571b061d92SChristoph Hellwig */ 115802c24a82SJosef Bacik int noop_fsync(struct file *file, loff_t start, loff_t end, int datasync) 11591b061d92SChristoph Hellwig { 11601b061d92SChristoph Hellwig return 0; 11611b061d92SChristoph Hellwig } 11621b061d92SChristoph Hellwig EXPORT_SYMBOL(noop_fsync); 116387dc800bSAl Viro 1164f44c7763SDan Williams int noop_set_page_dirty(struct page *page) 1165f44c7763SDan Williams { 1166f44c7763SDan Williams /* 1167f44c7763SDan Williams * Unlike __set_page_dirty_no_writeback that handles dirty page 1168f44c7763SDan Williams * tracking in the page object, dax does all dirty tracking in 1169f44c7763SDan Williams * the inode address_space in response to mkwrite faults. In the 1170f44c7763SDan Williams * dax case we only need to worry about potentially dirty CPU 1171f44c7763SDan Williams * caches, not dirty page cache pages to write back. 1172f44c7763SDan Williams * 1173f44c7763SDan Williams * This callback is defined to prevent fallback to 1174f44c7763SDan Williams * __set_page_dirty_buffers() in set_page_dirty(). 1175f44c7763SDan Williams */ 1176f44c7763SDan Williams return 0; 1177f44c7763SDan Williams } 1178f44c7763SDan Williams EXPORT_SYMBOL_GPL(noop_set_page_dirty); 1179f44c7763SDan Williams 1180f44c7763SDan Williams void noop_invalidatepage(struct page *page, unsigned int offset, 1181f44c7763SDan Williams unsigned int length) 1182f44c7763SDan Williams { 1183f44c7763SDan Williams /* 1184f44c7763SDan Williams * There is no page cache to invalidate in the dax case, however 1185f44c7763SDan Williams * we need this callback defined to prevent falling back to 1186f44c7763SDan Williams * block_invalidatepage() in do_invalidatepage(). 1187f44c7763SDan Williams */ 1188f44c7763SDan Williams } 1189f44c7763SDan Williams EXPORT_SYMBOL_GPL(noop_invalidatepage); 1190f44c7763SDan Williams 1191f44c7763SDan Williams ssize_t noop_direct_IO(struct kiocb *iocb, struct iov_iter *iter) 1192f44c7763SDan Williams { 1193f44c7763SDan Williams /* 1194f44c7763SDan Williams * iomap based filesystems support direct I/O without need for 1195f44c7763SDan Williams * this callback. However, it still needs to be set in 1196f44c7763SDan Williams * inode->a_ops so that open/fcntl know that direct I/O is 1197f44c7763SDan Williams * generally supported. 1198f44c7763SDan Williams */ 1199f44c7763SDan Williams return -EINVAL; 1200f44c7763SDan Williams } 1201f44c7763SDan Williams EXPORT_SYMBOL_GPL(noop_direct_IO); 1202f44c7763SDan Williams 1203fceef393SAl Viro /* Because kfree isn't assignment-compatible with void(void*) ;-/ */ 1204fceef393SAl Viro void kfree_link(void *p) 120587dc800bSAl Viro { 1206fceef393SAl Viro kfree(p); 120787dc800bSAl Viro } 1208fceef393SAl Viro EXPORT_SYMBOL(kfree_link); 12096987843fSAl Viro 12106987843fSAl Viro /* 12116987843fSAl Viro * nop .set_page_dirty method so that people can use .page_mkwrite on 12126987843fSAl Viro * anon inodes. 12136987843fSAl Viro */ 12146987843fSAl Viro static int anon_set_page_dirty(struct page *page) 12156987843fSAl Viro { 12166987843fSAl Viro return 0; 12176987843fSAl Viro }; 12186987843fSAl Viro 12196987843fSAl Viro /* 12206987843fSAl Viro * A single inode exists for all anon_inode files. Contrary to pipes, 12216987843fSAl Viro * anon_inode inodes have no associated per-instance data, so we need 12226987843fSAl Viro * only allocate one of them. 12236987843fSAl Viro */ 12246987843fSAl Viro struct inode *alloc_anon_inode(struct super_block *s) 12256987843fSAl Viro { 12266987843fSAl Viro static const struct address_space_operations anon_aops = { 12276987843fSAl Viro .set_page_dirty = anon_set_page_dirty, 12286987843fSAl Viro }; 12296987843fSAl Viro struct inode *inode = new_inode_pseudo(s); 12306987843fSAl Viro 12316987843fSAl Viro if (!inode) 12326987843fSAl Viro return ERR_PTR(-ENOMEM); 12336987843fSAl Viro 12346987843fSAl Viro inode->i_ino = get_next_ino(); 12356987843fSAl Viro inode->i_mapping->a_ops = &anon_aops; 12366987843fSAl Viro 12376987843fSAl Viro /* 12386987843fSAl Viro * Mark the inode dirty from the very beginning, 12396987843fSAl Viro * that way it will never be moved to the dirty 12406987843fSAl Viro * list because mark_inode_dirty() will think 12416987843fSAl Viro * that it already _is_ on the dirty list. 12426987843fSAl Viro */ 12436987843fSAl Viro inode->i_state = I_DIRTY; 12446987843fSAl Viro inode->i_mode = S_IRUSR | S_IWUSR; 12456987843fSAl Viro inode->i_uid = current_fsuid(); 12466987843fSAl Viro inode->i_gid = current_fsgid(); 12476987843fSAl Viro inode->i_flags |= S_PRIVATE; 1248078cd827SDeepa Dinamani inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode); 12496987843fSAl Viro return inode; 12506987843fSAl Viro } 12516987843fSAl Viro EXPORT_SYMBOL(alloc_anon_inode); 12521c994a09SJeff Layton 12531c994a09SJeff Layton /** 12541c994a09SJeff Layton * simple_nosetlease - generic helper for prohibiting leases 12551c994a09SJeff Layton * @filp: file pointer 12561c994a09SJeff Layton * @arg: type of lease to obtain 12571c994a09SJeff Layton * @flp: new lease supplied for insertion 1258e6f5c789SJeff Layton * @priv: private data for lm_setup operation 12591c994a09SJeff Layton * 12601c994a09SJeff Layton * Generic helper for filesystems that do not wish to allow leases to be set. 12611c994a09SJeff Layton * All arguments are ignored and it just returns -EINVAL. 12621c994a09SJeff Layton */ 12631c994a09SJeff Layton int 1264e6f5c789SJeff Layton simple_nosetlease(struct file *filp, long arg, struct file_lock **flp, 1265e6f5c789SJeff Layton void **priv) 12661c994a09SJeff Layton { 12671c994a09SJeff Layton return -EINVAL; 12681c994a09SJeff Layton } 12691c994a09SJeff Layton EXPORT_SYMBOL(simple_nosetlease); 127061ba64fcSAl Viro 12716ee9706aSEric Biggers /** 12726ee9706aSEric Biggers * simple_get_link - generic helper to get the target of "fast" symlinks 12736ee9706aSEric Biggers * @dentry: not used here 12746ee9706aSEric Biggers * @inode: the symlink inode 12756ee9706aSEric Biggers * @done: not used here 12766ee9706aSEric Biggers * 12776ee9706aSEric Biggers * Generic helper for filesystems to use for symlink inodes where a pointer to 12786ee9706aSEric Biggers * the symlink target is stored in ->i_link. NOTE: this isn't normally called, 12796ee9706aSEric Biggers * since as an optimization the path lookup code uses any non-NULL ->i_link 12806ee9706aSEric Biggers * directly, without calling ->get_link(). But ->get_link() still must be set, 12816ee9706aSEric Biggers * to mark the inode_operations as being for a symlink. 12826ee9706aSEric Biggers * 12836ee9706aSEric Biggers * Return: the symlink target 12846ee9706aSEric Biggers */ 12856b255391SAl Viro const char *simple_get_link(struct dentry *dentry, struct inode *inode, 1286fceef393SAl Viro struct delayed_call *done) 128761ba64fcSAl Viro { 12886b255391SAl Viro return inode->i_link; 128961ba64fcSAl Viro } 12906b255391SAl Viro EXPORT_SYMBOL(simple_get_link); 129161ba64fcSAl Viro 129261ba64fcSAl Viro const struct inode_operations simple_symlink_inode_operations = { 12936b255391SAl Viro .get_link = simple_get_link, 129461ba64fcSAl Viro }; 129561ba64fcSAl Viro EXPORT_SYMBOL(simple_symlink_inode_operations); 1296fbabfd0fSEric W. Biederman 1297fbabfd0fSEric W. Biederman /* 1298fbabfd0fSEric W. Biederman * Operations for a permanently empty directory. 1299fbabfd0fSEric W. Biederman */ 1300fbabfd0fSEric W. Biederman static struct dentry *empty_dir_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) 1301fbabfd0fSEric W. Biederman { 1302fbabfd0fSEric W. Biederman return ERR_PTR(-ENOENT); 1303fbabfd0fSEric W. Biederman } 1304fbabfd0fSEric W. Biederman 1305*549c7297SChristian Brauner static int empty_dir_getattr(struct user_namespace *mnt_userns, 1306*549c7297SChristian Brauner const struct path *path, struct kstat *stat, 1307a528d35eSDavid Howells u32 request_mask, unsigned int query_flags) 1308fbabfd0fSEric W. Biederman { 1309a528d35eSDavid Howells struct inode *inode = d_inode(path->dentry); 13100d56a451SChristian Brauner generic_fillattr(&init_user_ns, inode, stat); 1311fbabfd0fSEric W. Biederman return 0; 1312fbabfd0fSEric W. Biederman } 1313fbabfd0fSEric W. Biederman 1314*549c7297SChristian Brauner static int empty_dir_setattr(struct user_namespace *mnt_userns, 1315*549c7297SChristian Brauner struct dentry *dentry, struct iattr *attr) 1316fbabfd0fSEric W. Biederman { 1317fbabfd0fSEric W. Biederman return -EPERM; 1318fbabfd0fSEric W. Biederman } 1319fbabfd0fSEric W. Biederman 1320fbabfd0fSEric W. Biederman static ssize_t empty_dir_listxattr(struct dentry *dentry, char *list, size_t size) 1321fbabfd0fSEric W. Biederman { 1322fbabfd0fSEric W. Biederman return -EOPNOTSUPP; 1323fbabfd0fSEric W. Biederman } 1324fbabfd0fSEric W. Biederman 1325fbabfd0fSEric W. Biederman static const struct inode_operations empty_dir_inode_operations = { 1326fbabfd0fSEric W. Biederman .lookup = empty_dir_lookup, 1327*549c7297SChristian Brauner .permission = generic_permission, 1328fbabfd0fSEric W. Biederman .setattr = empty_dir_setattr, 1329fbabfd0fSEric W. Biederman .getattr = empty_dir_getattr, 1330fbabfd0fSEric W. Biederman .listxattr = empty_dir_listxattr, 1331fbabfd0fSEric W. Biederman }; 1332fbabfd0fSEric W. Biederman 1333fbabfd0fSEric W. Biederman static loff_t empty_dir_llseek(struct file *file, loff_t offset, int whence) 1334fbabfd0fSEric W. Biederman { 1335fbabfd0fSEric W. Biederman /* An empty directory has two entries . and .. at offsets 0 and 1 */ 1336fbabfd0fSEric W. Biederman return generic_file_llseek_size(file, offset, whence, 2, 2); 1337fbabfd0fSEric W. Biederman } 1338fbabfd0fSEric W. Biederman 1339fbabfd0fSEric W. Biederman static int empty_dir_readdir(struct file *file, struct dir_context *ctx) 1340fbabfd0fSEric W. Biederman { 1341fbabfd0fSEric W. Biederman dir_emit_dots(file, ctx); 1342fbabfd0fSEric W. Biederman return 0; 1343fbabfd0fSEric W. Biederman } 1344fbabfd0fSEric W. Biederman 1345fbabfd0fSEric W. Biederman static const struct file_operations empty_dir_operations = { 1346fbabfd0fSEric W. Biederman .llseek = empty_dir_llseek, 1347fbabfd0fSEric W. Biederman .read = generic_read_dir, 1348c51da20cSAl Viro .iterate_shared = empty_dir_readdir, 1349fbabfd0fSEric W. Biederman .fsync = noop_fsync, 1350fbabfd0fSEric W. Biederman }; 1351fbabfd0fSEric W. Biederman 1352fbabfd0fSEric W. Biederman 1353fbabfd0fSEric W. Biederman void make_empty_dir_inode(struct inode *inode) 1354fbabfd0fSEric W. Biederman { 1355fbabfd0fSEric W. Biederman set_nlink(inode, 2); 1356fbabfd0fSEric W. Biederman inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO; 1357fbabfd0fSEric W. Biederman inode->i_uid = GLOBAL_ROOT_UID; 1358fbabfd0fSEric W. Biederman inode->i_gid = GLOBAL_ROOT_GID; 1359fbabfd0fSEric W. Biederman inode->i_rdev = 0; 13604b75de86SEric W. Biederman inode->i_size = 0; 1361fbabfd0fSEric W. Biederman inode->i_blkbits = PAGE_SHIFT; 1362fbabfd0fSEric W. Biederman inode->i_blocks = 0; 1363fbabfd0fSEric W. Biederman 1364fbabfd0fSEric W. Biederman inode->i_op = &empty_dir_inode_operations; 1365f5c24438SAndreas Gruenbacher inode->i_opflags &= ~IOP_XATTR; 1366fbabfd0fSEric W. Biederman inode->i_fop = &empty_dir_operations; 1367fbabfd0fSEric W. Biederman } 1368fbabfd0fSEric W. Biederman 1369fbabfd0fSEric W. Biederman bool is_empty_dir_inode(struct inode *inode) 1370fbabfd0fSEric W. Biederman { 1371fbabfd0fSEric W. Biederman return (inode->i_fop == &empty_dir_operations) && 1372fbabfd0fSEric W. Biederman (inode->i_op == &empty_dir_inode_operations); 1373fbabfd0fSEric W. Biederman } 1374c843843eSDaniel Rosenberg 1375c843843eSDaniel Rosenberg #ifdef CONFIG_UNICODE 1376c843843eSDaniel Rosenberg /* 1377c843843eSDaniel Rosenberg * Determine if the name of a dentry should be casefolded. 1378c843843eSDaniel Rosenberg * 1379c843843eSDaniel Rosenberg * Return: if names will need casefolding 1380c843843eSDaniel Rosenberg */ 1381c843843eSDaniel Rosenberg static bool needs_casefold(const struct inode *dir) 1382c843843eSDaniel Rosenberg { 1383c843843eSDaniel Rosenberg return IS_CASEFOLDED(dir) && dir->i_sb->s_encoding; 1384c843843eSDaniel Rosenberg } 1385c843843eSDaniel Rosenberg 1386c843843eSDaniel Rosenberg /** 1387c843843eSDaniel Rosenberg * generic_ci_d_compare - generic d_compare implementation for casefolding filesystems 1388c843843eSDaniel Rosenberg * @dentry: dentry whose name we are checking against 1389c843843eSDaniel Rosenberg * @len: len of name of dentry 1390c843843eSDaniel Rosenberg * @str: str pointer to name of dentry 1391c843843eSDaniel Rosenberg * @name: Name to compare against 1392c843843eSDaniel Rosenberg * 1393c843843eSDaniel Rosenberg * Return: 0 if names match, 1 if mismatch, or -ERRNO 1394c843843eSDaniel Rosenberg */ 1395c843843eSDaniel Rosenberg int generic_ci_d_compare(const struct dentry *dentry, unsigned int len, 1396c843843eSDaniel Rosenberg const char *str, const struct qstr *name) 1397c843843eSDaniel Rosenberg { 1398c843843eSDaniel Rosenberg const struct dentry *parent = READ_ONCE(dentry->d_parent); 1399c843843eSDaniel Rosenberg const struct inode *dir = READ_ONCE(parent->d_inode); 1400c843843eSDaniel Rosenberg const struct super_block *sb = dentry->d_sb; 1401c843843eSDaniel Rosenberg const struct unicode_map *um = sb->s_encoding; 1402c843843eSDaniel Rosenberg struct qstr qstr = QSTR_INIT(str, len); 1403c843843eSDaniel Rosenberg char strbuf[DNAME_INLINE_LEN]; 1404c843843eSDaniel Rosenberg int ret; 1405c843843eSDaniel Rosenberg 1406c843843eSDaniel Rosenberg if (!dir || !needs_casefold(dir)) 1407c843843eSDaniel Rosenberg goto fallback; 1408c843843eSDaniel Rosenberg /* 1409c843843eSDaniel Rosenberg * If the dentry name is stored in-line, then it may be concurrently 1410c843843eSDaniel Rosenberg * modified by a rename. If this happens, the VFS will eventually retry 1411c843843eSDaniel Rosenberg * the lookup, so it doesn't matter what ->d_compare() returns. 1412c843843eSDaniel Rosenberg * However, it's unsafe to call utf8_strncasecmp() with an unstable 1413c843843eSDaniel Rosenberg * string. Therefore, we have to copy the name into a temporary buffer. 1414c843843eSDaniel Rosenberg */ 1415c843843eSDaniel Rosenberg if (len <= DNAME_INLINE_LEN - 1) { 1416c843843eSDaniel Rosenberg memcpy(strbuf, str, len); 1417c843843eSDaniel Rosenberg strbuf[len] = 0; 1418c843843eSDaniel Rosenberg qstr.name = strbuf; 1419c843843eSDaniel Rosenberg /* prevent compiler from optimizing out the temporary buffer */ 1420c843843eSDaniel Rosenberg barrier(); 1421c843843eSDaniel Rosenberg } 1422c843843eSDaniel Rosenberg ret = utf8_strncasecmp(um, name, &qstr); 1423c843843eSDaniel Rosenberg if (ret >= 0) 1424c843843eSDaniel Rosenberg return ret; 1425c843843eSDaniel Rosenberg 1426c843843eSDaniel Rosenberg if (sb_has_strict_encoding(sb)) 1427c843843eSDaniel Rosenberg return -EINVAL; 1428c843843eSDaniel Rosenberg fallback: 1429c843843eSDaniel Rosenberg if (len != name->len) 1430c843843eSDaniel Rosenberg return 1; 1431c843843eSDaniel Rosenberg return !!memcmp(str, name->name, len); 1432c843843eSDaniel Rosenberg } 1433c843843eSDaniel Rosenberg EXPORT_SYMBOL(generic_ci_d_compare); 1434c843843eSDaniel Rosenberg 1435c843843eSDaniel Rosenberg /** 1436c843843eSDaniel Rosenberg * generic_ci_d_hash - generic d_hash implementation for casefolding filesystems 1437c843843eSDaniel Rosenberg * @dentry: dentry of the parent directory 1438c843843eSDaniel Rosenberg * @str: qstr of name whose hash we should fill in 1439c843843eSDaniel Rosenberg * 1440c843843eSDaniel Rosenberg * Return: 0 if hash was successful or unchanged, and -EINVAL on error 1441c843843eSDaniel Rosenberg */ 1442c843843eSDaniel Rosenberg int generic_ci_d_hash(const struct dentry *dentry, struct qstr *str) 1443c843843eSDaniel Rosenberg { 1444c843843eSDaniel Rosenberg const struct inode *dir = READ_ONCE(dentry->d_inode); 1445c843843eSDaniel Rosenberg struct super_block *sb = dentry->d_sb; 1446c843843eSDaniel Rosenberg const struct unicode_map *um = sb->s_encoding; 1447c843843eSDaniel Rosenberg int ret = 0; 1448c843843eSDaniel Rosenberg 1449c843843eSDaniel Rosenberg if (!dir || !needs_casefold(dir)) 1450c843843eSDaniel Rosenberg return 0; 1451c843843eSDaniel Rosenberg 1452c843843eSDaniel Rosenberg ret = utf8_casefold_hash(um, dentry, str); 1453c843843eSDaniel Rosenberg if (ret < 0 && sb_has_strict_encoding(sb)) 1454c843843eSDaniel Rosenberg return -EINVAL; 1455c843843eSDaniel Rosenberg return 0; 1456c843843eSDaniel Rosenberg } 1457c843843eSDaniel Rosenberg EXPORT_SYMBOL(generic_ci_d_hash); 1458608af703SDaniel Rosenberg 1459608af703SDaniel Rosenberg static const struct dentry_operations generic_ci_dentry_ops = { 1460608af703SDaniel Rosenberg .d_hash = generic_ci_d_hash, 1461608af703SDaniel Rosenberg .d_compare = generic_ci_d_compare, 1462608af703SDaniel Rosenberg }; 1463c843843eSDaniel Rosenberg #endif 1464608af703SDaniel Rosenberg 1465608af703SDaniel Rosenberg #ifdef CONFIG_FS_ENCRYPTION 1466608af703SDaniel Rosenberg static const struct dentry_operations generic_encrypted_dentry_ops = { 1467608af703SDaniel Rosenberg .d_revalidate = fscrypt_d_revalidate, 1468608af703SDaniel Rosenberg }; 1469608af703SDaniel Rosenberg #endif 1470608af703SDaniel Rosenberg 1471608af703SDaniel Rosenberg #if defined(CONFIG_FS_ENCRYPTION) && defined(CONFIG_UNICODE) 1472608af703SDaniel Rosenberg static const struct dentry_operations generic_encrypted_ci_dentry_ops = { 1473608af703SDaniel Rosenberg .d_hash = generic_ci_d_hash, 1474608af703SDaniel Rosenberg .d_compare = generic_ci_d_compare, 1475608af703SDaniel Rosenberg .d_revalidate = fscrypt_d_revalidate, 1476608af703SDaniel Rosenberg }; 1477608af703SDaniel Rosenberg #endif 1478608af703SDaniel Rosenberg 1479608af703SDaniel Rosenberg /** 1480608af703SDaniel Rosenberg * generic_set_encrypted_ci_d_ops - helper for setting d_ops for given dentry 1481608af703SDaniel Rosenberg * @dentry: dentry to set ops on 1482608af703SDaniel Rosenberg * 1483608af703SDaniel Rosenberg * Casefolded directories need d_hash and d_compare set, so that the dentries 1484608af703SDaniel Rosenberg * contained in them are handled case-insensitively. Note that these operations 1485608af703SDaniel Rosenberg * are needed on the parent directory rather than on the dentries in it, and 1486608af703SDaniel Rosenberg * while the casefolding flag can be toggled on and off on an empty directory, 1487608af703SDaniel Rosenberg * dentry_operations can't be changed later. As a result, if the filesystem has 1488608af703SDaniel Rosenberg * casefolding support enabled at all, we have to give all dentries the 1489608af703SDaniel Rosenberg * casefolding operations even if their inode doesn't have the casefolding flag 1490608af703SDaniel Rosenberg * currently (and thus the casefolding ops would be no-ops for now). 1491608af703SDaniel Rosenberg * 1492608af703SDaniel Rosenberg * Encryption works differently in that the only dentry operation it needs is 1493608af703SDaniel Rosenberg * d_revalidate, which it only needs on dentries that have the no-key name flag. 1494608af703SDaniel Rosenberg * The no-key flag can't be set "later", so we don't have to worry about that. 1495608af703SDaniel Rosenberg * 1496608af703SDaniel Rosenberg * Finally, to maximize compatibility with overlayfs (which isn't compatible 1497608af703SDaniel Rosenberg * with certain dentry operations) and to avoid taking an unnecessary 1498608af703SDaniel Rosenberg * performance hit, we use custom dentry_operations for each possible 1499608af703SDaniel Rosenberg * combination rather than always installing all operations. 1500608af703SDaniel Rosenberg */ 1501608af703SDaniel Rosenberg void generic_set_encrypted_ci_d_ops(struct dentry *dentry) 1502608af703SDaniel Rosenberg { 1503608af703SDaniel Rosenberg #ifdef CONFIG_FS_ENCRYPTION 1504608af703SDaniel Rosenberg bool needs_encrypt_ops = dentry->d_flags & DCACHE_NOKEY_NAME; 1505608af703SDaniel Rosenberg #endif 1506608af703SDaniel Rosenberg #ifdef CONFIG_UNICODE 1507608af703SDaniel Rosenberg bool needs_ci_ops = dentry->d_sb->s_encoding; 1508608af703SDaniel Rosenberg #endif 1509608af703SDaniel Rosenberg #if defined(CONFIG_FS_ENCRYPTION) && defined(CONFIG_UNICODE) 1510608af703SDaniel Rosenberg if (needs_encrypt_ops && needs_ci_ops) { 1511608af703SDaniel Rosenberg d_set_d_op(dentry, &generic_encrypted_ci_dentry_ops); 1512608af703SDaniel Rosenberg return; 1513608af703SDaniel Rosenberg } 1514608af703SDaniel Rosenberg #endif 1515608af703SDaniel Rosenberg #ifdef CONFIG_FS_ENCRYPTION 1516608af703SDaniel Rosenberg if (needs_encrypt_ops) { 1517608af703SDaniel Rosenberg d_set_d_op(dentry, &generic_encrypted_dentry_ops); 1518608af703SDaniel Rosenberg return; 1519608af703SDaniel Rosenberg } 1520608af703SDaniel Rosenberg #endif 1521608af703SDaniel Rosenberg #ifdef CONFIG_UNICODE 1522608af703SDaniel Rosenberg if (needs_ci_ops) { 1523608af703SDaniel Rosenberg d_set_d_op(dentry, &generic_ci_dentry_ops); 1524608af703SDaniel Rosenberg return; 1525608af703SDaniel Rosenberg } 1526608af703SDaniel Rosenberg #endif 1527608af703SDaniel Rosenberg } 1528608af703SDaniel Rosenberg EXPORT_SYMBOL(generic_set_encrypted_ci_d_ops); 1529