Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | #ifndef __LINUX_DCACHE_H |
| 2 | #define __LINUX_DCACHE_H |
| 3 | |
Arun Sharma | 60063497 | 2011-07-26 16:09:06 -0700 | [diff] [blame] | 4 | #include <linux/atomic.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 5 | #include <linux/list.h> |
Franck Bui-Huu | 8252474 | 2008-05-12 21:21:05 +0200 | [diff] [blame] | 6 | #include <linux/rculist.h> |
Nick Piggin | ceb5bdc | 2011-01-07 17:50:05 +1100 | [diff] [blame] | 7 | #include <linux/rculist_bl.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 8 | #include <linux/spinlock.h> |
Nick Piggin | 31e6b01 | 2011-01-07 17:49:52 +1100 | [diff] [blame] | 9 | #include <linux/seqlock.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 10 | #include <linux/cache.h> |
| 11 | #include <linux/rcupdate.h> |
Waiman Long | 9847423 | 2013-08-28 18:24:59 -0700 | [diff] [blame] | 12 | #include <linux/lockref.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 13 | |
| 14 | struct nameidata; |
Jan Blunck | cf28b48 | 2008-02-14 19:38:44 -0800 | [diff] [blame] | 15 | struct path; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 16 | struct vfsmount; |
| 17 | |
| 18 | /* |
| 19 | * linux/include/linux/dcache.h |
| 20 | * |
| 21 | * Dirent cache data structures |
| 22 | * |
| 23 | * (C) Copyright 1997 Thomas Schoebel-Theuer, |
| 24 | * with heavy changes by Linus Torvalds |
| 25 | */ |
| 26 | |
| 27 | #define IS_ROOT(x) ((x) == (x)->d_parent) |
| 28 | |
Linus Torvalds | 26fe575 | 2012-05-10 13:14:12 -0700 | [diff] [blame] | 29 | /* The hash is always the low bits of hash_len */ |
| 30 | #ifdef __LITTLE_ENDIAN |
| 31 | #define HASH_LEN_DECLARE u32 hash; u32 len; |
| 32 | #else |
| 33 | #define HASH_LEN_DECLARE u32 len; u32 hash; |
| 34 | #endif |
| 35 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 36 | /* |
| 37 | * "quick string" -- eases parameter passing, but more importantly |
| 38 | * saves "metadata" about the string (ie length and the hash). |
| 39 | * |
| 40 | * hash comes first so it snuggles against d_parent in the |
| 41 | * dentry. |
| 42 | */ |
| 43 | struct qstr { |
Linus Torvalds | 26fe575 | 2012-05-10 13:14:12 -0700 | [diff] [blame] | 44 | union { |
| 45 | struct { |
| 46 | HASH_LEN_DECLARE; |
| 47 | }; |
| 48 | u64 hash_len; |
| 49 | }; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 50 | const unsigned char *name; |
| 51 | }; |
| 52 | |
Linus Torvalds | 26fe575 | 2012-05-10 13:14:12 -0700 | [diff] [blame] | 53 | #define QSTR_INIT(n,l) { { { .len = l } }, .name = n } |
| 54 | #define hashlen_hash(hashlen) ((u32) (hashlen)) |
| 55 | #define hashlen_len(hashlen) ((u32)((hashlen) >> 32)) |
| 56 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 57 | struct dentry_stat_t { |
Glauber Costa | 3942c07 | 2013-08-28 10:17:53 +1000 | [diff] [blame] | 58 | long nr_dentry; |
| 59 | long nr_unused; |
| 60 | long age_limit; /* age in seconds */ |
| 61 | long want_pages; /* pages requested by system */ |
| 62 | long dummy[2]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 63 | }; |
| 64 | extern struct dentry_stat_t dentry_stat; |
| 65 | |
| 66 | /* Name hashing routines. Initial hash value */ |
| 67 | /* Hash courtesy of the R5 hash in reiserfs modulo sign bits */ |
| 68 | #define init_name_hash() 0 |
| 69 | |
| 70 | /* partial hash update function. Assume roughly 4 bits per character */ |
| 71 | static inline unsigned long |
| 72 | partial_name_hash(unsigned long c, unsigned long prevhash) |
| 73 | { |
| 74 | return (prevhash + (c << 4) + (c >> 4)) * 11; |
| 75 | } |
| 76 | |
| 77 | /* |
| 78 | * Finally: cut down the number of bits to a int value (and try to avoid |
| 79 | * losing bits) |
| 80 | */ |
| 81 | static inline unsigned long end_name_hash(unsigned long hash) |
| 82 | { |
| 83 | return (unsigned int) hash; |
| 84 | } |
| 85 | |
| 86 | /* Compute the hash for a name string. */ |
Linus Torvalds | 0145acc | 2012-03-02 14:32:59 -0800 | [diff] [blame] | 87 | extern unsigned int full_name_hash(const unsigned char *, unsigned int); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 88 | |
Nick Piggin | c2452f3 | 2008-12-01 09:33:43 +0100 | [diff] [blame] | 89 | /* |
| 90 | * Try to keep struct dentry aligned on 64 byte cachelines (this will |
| 91 | * give reasonable cacheline footprint with larger lines without the |
| 92 | * large memory footprint increase). |
| 93 | */ |
| 94 | #ifdef CONFIG_64BIT |
Nick Piggin | 44a7d7a | 2011-01-07 17:49:56 +1100 | [diff] [blame] | 95 | # define DNAME_INLINE_LEN 32 /* 192 bytes */ |
Nick Piggin | c2452f3 | 2008-12-01 09:33:43 +0100 | [diff] [blame] | 96 | #else |
Nick Piggin | 44a7d7a | 2011-01-07 17:49:56 +1100 | [diff] [blame] | 97 | # ifdef CONFIG_SMP |
| 98 | # define DNAME_INLINE_LEN 36 /* 128 bytes */ |
| 99 | # else |
| 100 | # define DNAME_INLINE_LEN 40 /* 128 bytes */ |
| 101 | # endif |
Nick Piggin | c2452f3 | 2008-12-01 09:33:43 +0100 | [diff] [blame] | 102 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 103 | |
Waiman Long | 9847423 | 2013-08-28 18:24:59 -0700 | [diff] [blame] | 104 | #define d_lock d_lockref.lock |
| 105 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 106 | struct dentry { |
Nick Piggin | 44a7d7a | 2011-01-07 17:49:56 +1100 | [diff] [blame] | 107 | /* RCU lookup touched fields */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 108 | unsigned int d_flags; /* protected by d_lock */ |
Nick Piggin | 31e6b01 | 2011-01-07 17:49:52 +1100 | [diff] [blame] | 109 | seqcount_t d_seq; /* per dentry seqlock */ |
Nick Piggin | ceb5bdc | 2011-01-07 17:50:05 +1100 | [diff] [blame] | 110 | struct hlist_bl_node d_hash; /* lookup hash list */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 111 | struct dentry *d_parent; /* parent directory */ |
| 112 | struct qstr d_name; |
Nick Piggin | 44a7d7a | 2011-01-07 17:49:56 +1100 | [diff] [blame] | 113 | struct inode *d_inode; /* Where the name belongs to - NULL is |
| 114 | * negative */ |
| 115 | unsigned char d_iname[DNAME_INLINE_LEN]; /* small names */ |
| 116 | |
| 117 | /* Ref lookup also touches following */ |
Waiman Long | 9847423 | 2013-08-28 18:24:59 -0700 | [diff] [blame] | 118 | struct lockref d_lockref; /* per-dentry lock and refcount */ |
Nick Piggin | 44a7d7a | 2011-01-07 17:49:56 +1100 | [diff] [blame] | 119 | const struct dentry_operations *d_op; |
| 120 | struct super_block *d_sb; /* The root of the dentry tree */ |
| 121 | unsigned long d_time; /* used by d_revalidate */ |
| 122 | void *d_fsdata; /* fs-specific data */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 123 | |
| 124 | struct list_head d_lru; /* LRU list */ |
Eric Dumazet | 5160ee6 | 2006-01-08 01:03:32 -0800 | [diff] [blame] | 125 | /* |
| 126 | * d_child and d_rcu can share memory |
| 127 | */ |
| 128 | union { |
| 129 | struct list_head d_child; /* child of parent list */ |
| 130 | struct rcu_head d_rcu; |
| 131 | } d_u; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 132 | struct list_head d_subdirs; /* our children */ |
Al Viro | b3d9b7a | 2012-06-09 13:51:19 -0400 | [diff] [blame] | 133 | struct hlist_node d_alias; /* inode alias list */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 134 | }; |
| 135 | |
Ingo Molnar | a90b9c0 | 2006-07-03 00:25:04 -0700 | [diff] [blame] | 136 | /* |
| 137 | * dentry->d_lock spinlock nesting subclasses: |
| 138 | * |
| 139 | * 0: normal |
| 140 | * 1: nested |
| 141 | */ |
| 142 | enum dentry_d_lock_class |
| 143 | { |
| 144 | DENTRY_D_LOCK_NORMAL, /* implicitly used by plain spin_lock() APIs. */ |
| 145 | DENTRY_D_LOCK_NESTED |
| 146 | }; |
| 147 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 148 | struct dentry_operations { |
Al Viro | 0b728e1 | 2012-06-10 16:03:43 -0400 | [diff] [blame] | 149 | int (*d_revalidate)(struct dentry *, unsigned int); |
Jeff Layton | ecf3d1f | 2013-02-20 11:19:05 -0500 | [diff] [blame] | 150 | int (*d_weak_revalidate)(struct dentry *, unsigned int); |
Linus Torvalds | da53be1 | 2013-05-21 15:22:44 -0700 | [diff] [blame] | 151 | int (*d_hash)(const struct dentry *, struct qstr *); |
| 152 | int (*d_compare)(const struct dentry *, const struct dentry *, |
Nick Piggin | 621e155 | 2011-01-07 17:49:27 +1100 | [diff] [blame] | 153 | unsigned int, const char *, const struct qstr *); |
Nick Piggin | fe15ce4 | 2011-01-07 17:49:23 +1100 | [diff] [blame] | 154 | int (*d_delete)(const struct dentry *); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 155 | void (*d_release)(struct dentry *); |
Sage Weil | f0023bc | 2011-10-28 10:02:42 -0700 | [diff] [blame] | 156 | void (*d_prune)(struct dentry *); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 157 | void (*d_iput)(struct dentry *, struct inode *); |
Eric Dumazet | c23fbb6 | 2007-05-08 00:26:18 -0700 | [diff] [blame] | 158 | char *(*d_dname)(struct dentry *, char *, int); |
David Howells | 9875cf8 | 2011-01-14 18:45:21 +0000 | [diff] [blame] | 159 | struct vfsmount *(*d_automount)(struct path *); |
Al Viro | 1aed3e4 | 2011-03-18 09:09:02 -0400 | [diff] [blame] | 160 | int (*d_manage)(struct dentry *, bool); |
Nick Piggin | 44a7d7a | 2011-01-07 17:49:56 +1100 | [diff] [blame] | 161 | } ____cacheline_aligned; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 162 | |
Nick Piggin | 5eef7fa | 2011-01-07 17:49:22 +1100 | [diff] [blame] | 163 | /* |
| 164 | * Locking rules for dentry_operations callbacks are to be found in |
| 165 | * Documentation/filesystems/Locking. Keep it updated! |
| 166 | * |
Nick Piggin | 621e155 | 2011-01-07 17:49:27 +1100 | [diff] [blame] | 167 | * FUrther descriptions are found in Documentation/filesystems/vfs.txt. |
| 168 | * Keep it updated too! |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 169 | */ |
| 170 | |
| 171 | /* d_flags entries */ |
Linus Torvalds | 830c0f0 | 2011-08-06 22:41:50 -0700 | [diff] [blame] | 172 | #define DCACHE_OP_HASH 0x0001 |
| 173 | #define DCACHE_OP_COMPARE 0x0002 |
| 174 | #define DCACHE_OP_REVALIDATE 0x0004 |
| 175 | #define DCACHE_OP_DELETE 0x0008 |
Sage Weil | f0023bc | 2011-10-28 10:02:42 -0700 | [diff] [blame] | 176 | #define DCACHE_OP_PRUNE 0x0010 |
Nick Piggin | 5f57cbc | 2011-01-07 17:49:54 +1100 | [diff] [blame] | 177 | |
Sage Weil | f0023bc | 2011-10-28 10:02:42 -0700 | [diff] [blame] | 178 | #define DCACHE_DISCONNECTED 0x0020 |
Nick Piggin | 5f57cbc | 2011-01-07 17:49:54 +1100 | [diff] [blame] | 179 | /* This dentry is possibly not currently connected to the dcache tree, in |
| 180 | * which case its parent will either be itself, or will have this flag as |
| 181 | * well. nfsd will not use a dentry with this bit set, but will first |
| 182 | * endeavour to clear the bit either by discovering that it is connected, |
| 183 | * or by performing lookup operations. Any filesystem which supports |
| 184 | * nfsd_operations MUST have a lookup function which, if it finds a |
| 185 | * directory inode with a DCACHE_DISCONNECTED dentry, will d_move that |
| 186 | * dentry into place and return that dentry rather than the passed one, |
| 187 | * typically using d_splice_alias. */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 188 | |
Sage Weil | f0023bc | 2011-10-28 10:02:42 -0700 | [diff] [blame] | 189 | #define DCACHE_REFERENCED 0x0040 /* Recently used, don't discard. */ |
| 190 | #define DCACHE_RCUACCESS 0x0080 /* Entry has ever been RCU-visible */ |
Eric Paris | c28f7e5 | 2009-05-21 17:01:29 -0400 | [diff] [blame] | 191 | |
Al Viro | d83c49f | 2010-04-30 17:17:09 -0400 | [diff] [blame] | 192 | #define DCACHE_CANT_MOUNT 0x0100 |
Nick Piggin | 949854d | 2011-01-07 17:49:37 +1100 | [diff] [blame] | 193 | #define DCACHE_GENOCIDE 0x0200 |
Miklos Szeredi | eaf5f90 | 2012-01-10 18:22:25 +0100 | [diff] [blame] | 194 | #define DCACHE_SHRINK_LIST 0x0400 |
Nick Piggin | 5f57cbc | 2011-01-07 17:49:54 +1100 | [diff] [blame] | 195 | |
Jeff Layton | ecf3d1f | 2013-02-20 11:19:05 -0500 | [diff] [blame] | 196 | #define DCACHE_OP_WEAK_REVALIDATE 0x0800 |
| 197 | |
Linus Torvalds | 830c0f0 | 2011-08-06 22:41:50 -0700 | [diff] [blame] | 198 | #define DCACHE_NFSFS_RENAMED 0x1000 |
| 199 | /* this dentry has been "silly renamed" and has to be deleted on the last |
| 200 | * dput() */ |
| 201 | #define DCACHE_COOKIE 0x2000 /* For use by dcookie subsystem */ |
| 202 | #define DCACHE_FSNOTIFY_PARENT_WATCHED 0x4000 |
| 203 | /* Parent inode is watched by some fsnotify listener */ |
Nick Piggin | fb045ad | 2011-01-07 17:49:55 +1100 | [diff] [blame] | 204 | |
David Howells | 9875cf8 | 2011-01-14 18:45:21 +0000 | [diff] [blame] | 205 | #define DCACHE_MOUNTED 0x10000 /* is a mountpoint */ |
| 206 | #define DCACHE_NEED_AUTOMOUNT 0x20000 /* handle automount on this dir */ |
David Howells | cc53ce5 | 2011-01-14 18:45:26 +0000 | [diff] [blame] | 207 | #define DCACHE_MANAGE_TRANSIT 0x40000 /* manage transit from this dirent */ |
David Howells | 9875cf8 | 2011-01-14 18:45:21 +0000 | [diff] [blame] | 208 | #define DCACHE_MANAGED_DENTRY \ |
David Howells | cc53ce5 | 2011-01-14 18:45:26 +0000 | [diff] [blame] | 209 | (DCACHE_MOUNTED|DCACHE_NEED_AUTOMOUNT|DCACHE_MANAGE_TRANSIT) |
David Howells | 9875cf8 | 2011-01-14 18:45:21 +0000 | [diff] [blame] | 210 | |
Linus Torvalds | 8aab6a2 | 2013-09-08 13:26:18 -0700 | [diff] [blame] | 211 | #define DCACHE_LRU_LIST 0x80000 |
Miklos Szeredi | b161dfa6 | 2012-09-17 22:31:38 +0200 | [diff] [blame] | 212 | #define DCACHE_DENTRY_KILLED 0x100000 |
| 213 | |
Al Viro | 74c3cbe | 2007-07-22 08:04:18 -0400 | [diff] [blame] | 214 | extern seqlock_t rename_lock; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 215 | |
Al Viro | f0d3b3d | 2013-09-05 12:11:29 -0400 | [diff] [blame] | 216 | static inline int dname_external(const struct dentry *dentry) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 217 | { |
| 218 | return dentry->d_name.name != dentry->d_iname; |
| 219 | } |
| 220 | |
| 221 | /* |
| 222 | * These are the low-level FS interfaces to the dcache.. |
| 223 | */ |
| 224 | extern void d_instantiate(struct dentry *, struct inode *); |
| 225 | extern struct dentry * d_instantiate_unique(struct dentry *, struct inode *); |
David Howells | 770bfad | 2006-08-22 20:06:07 -0400 | [diff] [blame] | 226 | extern struct dentry * d_materialise_unique(struct dentry *, struct inode *); |
Nick Piggin | 789680d | 2011-01-07 17:49:30 +1100 | [diff] [blame] | 227 | extern void __d_drop(struct dentry *dentry); |
| 228 | extern void d_drop(struct dentry *dentry); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 229 | extern void d_delete(struct dentry *); |
Nick Piggin | fb045ad | 2011-01-07 17:49:55 +1100 | [diff] [blame] | 230 | extern void d_set_d_op(struct dentry *dentry, const struct dentry_operations *op); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 231 | |
| 232 | /* allocate/de-allocate */ |
| 233 | extern struct dentry * d_alloc(struct dentry *, const struct qstr *); |
Nick Piggin | 4b93688 | 2011-01-07 17:50:07 +1100 | [diff] [blame] | 234 | extern struct dentry * d_alloc_pseudo(struct super_block *, const struct qstr *); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 235 | extern struct dentry * d_splice_alias(struct inode *, struct dentry *); |
Christoph Hellwig | e45b590 | 2008-08-07 23:49:07 +0200 | [diff] [blame] | 236 | extern struct dentry * d_add_ci(struct dentry *, struct inode *, struct qstr *); |
Sage Weil | 46f72b3 | 2012-01-10 09:04:37 -0800 | [diff] [blame] | 237 | extern struct dentry *d_find_any_alias(struct inode *inode); |
Christoph Hellwig | 4ea3ada | 2008-08-11 15:48:57 +0200 | [diff] [blame] | 238 | extern struct dentry * d_obtain_alias(struct inode *); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 239 | extern void shrink_dcache_sb(struct super_block *); |
| 240 | extern void shrink_dcache_parent(struct dentry *); |
David Howells | c636ebd | 2006-10-11 01:22:19 -0700 | [diff] [blame] | 241 | extern void shrink_dcache_for_umount(struct super_block *); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 242 | extern int d_invalidate(struct dentry *); |
| 243 | |
| 244 | /* only used at mount-time */ |
Al Viro | adc0e91 | 2012-01-08 16:49:21 -0500 | [diff] [blame] | 245 | extern struct dentry * d_make_root(struct inode *); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 246 | |
| 247 | /* <clickety>-<click> the ramfs-type tree */ |
| 248 | extern void d_genocide(struct dentry *); |
| 249 | |
Al Viro | 60545d0 | 2013-06-07 01:20:27 -0400 | [diff] [blame] | 250 | extern void d_tmpfile(struct dentry *, struct inode *); |
| 251 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 252 | extern struct dentry *d_find_alias(struct inode *); |
| 253 | extern void d_prune_aliases(struct inode *); |
| 254 | |
| 255 | /* test whether we have any submounts in a subdir tree */ |
| 256 | extern int have_submounts(struct dentry *); |
Miklos Szeredi | 848ac114 | 2013-09-05 11:44:36 +0200 | [diff] [blame] | 257 | extern int check_submounts_and_drop(struct dentry *); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 258 | |
| 259 | /* |
| 260 | * This adds the entry to the hash queues. |
| 261 | */ |
| 262 | extern void d_rehash(struct dentry *); |
| 263 | |
| 264 | /** |
| 265 | * d_add - add dentry to hash queues |
| 266 | * @entry: dentry to add |
| 267 | * @inode: The inode to attach to this dentry |
| 268 | * |
| 269 | * This adds the entry to the hash queues and initializes @inode. |
| 270 | * The entry was actually filled in earlier during d_alloc(). |
| 271 | */ |
| 272 | |
| 273 | static inline void d_add(struct dentry *entry, struct inode *inode) |
| 274 | { |
| 275 | d_instantiate(entry, inode); |
| 276 | d_rehash(entry); |
| 277 | } |
| 278 | |
| 279 | /** |
| 280 | * d_add_unique - add dentry to hash queues without aliasing |
| 281 | * @entry: dentry to add |
| 282 | * @inode: The inode to attach to this dentry |
| 283 | * |
| 284 | * This adds the entry to the hash queues and initializes @inode. |
| 285 | * The entry was actually filled in earlier during d_alloc(). |
| 286 | */ |
| 287 | static inline struct dentry *d_add_unique(struct dentry *entry, struct inode *inode) |
| 288 | { |
| 289 | struct dentry *res; |
| 290 | |
| 291 | res = d_instantiate_unique(entry, inode); |
| 292 | d_rehash(res != NULL ? res : entry); |
| 293 | return res; |
| 294 | } |
| 295 | |
Nick Piggin | fb2d5b8 | 2011-01-07 17:49:26 +1100 | [diff] [blame] | 296 | extern void dentry_update_name_case(struct dentry *, struct qstr *); |
| 297 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 298 | /* used for rename() and baskets */ |
| 299 | extern void d_move(struct dentry *, struct dentry *); |
OGAWA Hirofumi | e2761a1 | 2008-10-16 07:50:28 +0900 | [diff] [blame] | 300 | extern struct dentry *d_ancestor(struct dentry *, struct dentry *); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 301 | |
| 302 | /* appendix may either be NULL or be used for transname suffixes */ |
Al Viro | da2d845 | 2013-01-24 18:29:34 -0500 | [diff] [blame] | 303 | extern struct dentry *d_lookup(const struct dentry *, const struct qstr *); |
Nick Piggin | 31e6b01 | 2011-01-07 17:49:52 +1100 | [diff] [blame] | 304 | extern struct dentry *d_hash_and_lookup(struct dentry *, struct qstr *); |
Al Viro | a713ca2 | 2013-01-24 18:27:00 -0500 | [diff] [blame] | 305 | extern struct dentry *__d_lookup(const struct dentry *, const struct qstr *); |
Linus Torvalds | 8966be9 | 2012-03-02 14:23:30 -0800 | [diff] [blame] | 306 | extern struct dentry *__d_lookup_rcu(const struct dentry *parent, |
Linus Torvalds | da53be1 | 2013-05-21 15:22:44 -0700 | [diff] [blame] | 307 | const struct qstr *name, unsigned *seq); |
Nick Piggin | 31e6b01 | 2011-01-07 17:49:52 +1100 | [diff] [blame] | 308 | |
Peng Tao | 24924a2 | 2013-07-18 22:09:08 +0800 | [diff] [blame] | 309 | static inline unsigned d_count(const struct dentry *dentry) |
Al Viro | 84d08fa | 2013-07-05 18:59:33 +0400 | [diff] [blame] | 310 | { |
Waiman Long | 9847423 | 2013-08-28 18:24:59 -0700 | [diff] [blame] | 311 | return dentry->d_lockref.count; |
Al Viro | 84d08fa | 2013-07-05 18:59:33 +0400 | [diff] [blame] | 312 | } |
| 313 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 314 | /* validate "insecure" dentry pointer */ |
| 315 | extern int d_validate(struct dentry *, struct dentry *); |
| 316 | |
Eric Dumazet | c23fbb6 | 2007-05-08 00:26:18 -0700 | [diff] [blame] | 317 | /* |
| 318 | * helper function for dentry_operations.d_dname() members |
| 319 | */ |
| 320 | extern char *dynamic_dname(struct dentry *, char *, int, const char *, ...); |
Al Viro | 118b230 | 2013-08-24 12:08:17 -0400 | [diff] [blame] | 321 | extern char *simple_dname(struct dentry *, char *, int); |
Eric Dumazet | c23fbb6 | 2007-05-08 00:26:18 -0700 | [diff] [blame] | 322 | |
Al Viro | 02125a8 | 2011-12-05 08:43:34 -0500 | [diff] [blame] | 323 | extern char *__d_path(const struct path *, const struct path *, char *, int); |
| 324 | extern char *d_absolute_path(const struct path *, char *, int); |
Jan Engelhardt | 20d4fdc | 2008-06-09 16:40:36 -0700 | [diff] [blame] | 325 | extern char *d_path(const struct path *, char *, int); |
Nick Piggin | ec2447c | 2011-01-07 17:49:29 +1100 | [diff] [blame] | 326 | extern char *dentry_path_raw(struct dentry *, char *, int); |
Ram Pai | 6092d04 | 2008-03-27 13:06:20 +0100 | [diff] [blame] | 327 | extern char *dentry_path(struct dentry *, char *, int); |
Jan Blunck | cf28b48 | 2008-02-14 19:38:44 -0800 | [diff] [blame] | 328 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 329 | /* Allocation counts.. */ |
| 330 | |
| 331 | /** |
Nick Piggin | dc0474b | 2011-01-07 17:49:43 +1100 | [diff] [blame] | 332 | * dget, dget_dlock - get a reference to a dentry |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 333 | * @dentry: dentry to get a reference to |
| 334 | * |
| 335 | * Given a dentry or %NULL pointer increment the reference count |
| 336 | * if appropriate and return the dentry. A dentry will not be |
Nick Piggin | dc0474b | 2011-01-07 17:49:43 +1100 | [diff] [blame] | 337 | * destroyed when it has references. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 338 | */ |
Nick Piggin | b7ab39f | 2011-01-07 17:49:32 +1100 | [diff] [blame] | 339 | static inline struct dentry *dget_dlock(struct dentry *dentry) |
| 340 | { |
Nick Piggin | dc0474b | 2011-01-07 17:49:43 +1100 | [diff] [blame] | 341 | if (dentry) |
Waiman Long | 9847423 | 2013-08-28 18:24:59 -0700 | [diff] [blame] | 342 | dentry->d_lockref.count++; |
Nick Piggin | b7ab39f | 2011-01-07 17:49:32 +1100 | [diff] [blame] | 343 | return dentry; |
| 344 | } |
Nick Piggin | 2fd6b7f | 2011-01-07 17:49:34 +1100 | [diff] [blame] | 345 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 346 | static inline struct dentry *dget(struct dentry *dentry) |
| 347 | { |
Waiman Long | 9847423 | 2013-08-28 18:24:59 -0700 | [diff] [blame] | 348 | if (dentry) |
| 349 | lockref_get(&dentry->d_lockref); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 350 | return dentry; |
| 351 | } |
| 352 | |
Nick Piggin | b7ab39f | 2011-01-07 17:49:32 +1100 | [diff] [blame] | 353 | extern struct dentry *dget_parent(struct dentry *dentry); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 354 | |
| 355 | /** |
| 356 | * d_unhashed - is dentry hashed |
| 357 | * @dentry: entry to check |
| 358 | * |
| 359 | * Returns true if the dentry passed is not currently hashed. |
| 360 | */ |
| 361 | |
Al Viro | f0d3b3d | 2013-09-05 12:11:29 -0400 | [diff] [blame] | 362 | static inline int d_unhashed(const struct dentry *dentry) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 363 | { |
Linus Torvalds | dea3667 | 2011-04-24 07:58:46 -0700 | [diff] [blame] | 364 | return hlist_bl_unhashed(&dentry->d_hash); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 365 | } |
| 366 | |
Al Viro | f0d3b3d | 2013-09-05 12:11:29 -0400 | [diff] [blame] | 367 | static inline int d_unlinked(const struct dentry *dentry) |
Alexey Dobriyan | f3da392 | 2009-05-04 03:32:03 +0400 | [diff] [blame] | 368 | { |
| 369 | return d_unhashed(dentry) && !IS_ROOT(dentry); |
| 370 | } |
| 371 | |
Al Viro | f0d3b3d | 2013-09-05 12:11:29 -0400 | [diff] [blame] | 372 | static inline int cant_mount(const struct dentry *dentry) |
Al Viro | d83c49f | 2010-04-30 17:17:09 -0400 | [diff] [blame] | 373 | { |
| 374 | return (dentry->d_flags & DCACHE_CANT_MOUNT); |
| 375 | } |
| 376 | |
| 377 | static inline void dont_mount(struct dentry *dentry) |
| 378 | { |
| 379 | spin_lock(&dentry->d_lock); |
| 380 | dentry->d_flags |= DCACHE_CANT_MOUNT; |
| 381 | spin_unlock(&dentry->d_lock); |
| 382 | } |
| 383 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 384 | extern void dput(struct dentry *); |
| 385 | |
Al Viro | f0d3b3d | 2013-09-05 12:11:29 -0400 | [diff] [blame] | 386 | static inline bool d_managed(const struct dentry *dentry) |
David Howells | cc53ce5 | 2011-01-14 18:45:26 +0000 | [diff] [blame] | 387 | { |
| 388 | return dentry->d_flags & DCACHE_MANAGED_DENTRY; |
| 389 | } |
| 390 | |
Al Viro | f0d3b3d | 2013-09-05 12:11:29 -0400 | [diff] [blame] | 391 | static inline bool d_mountpoint(const struct dentry *dentry) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 392 | { |
Nick Piggin | 5f57cbc | 2011-01-07 17:49:54 +1100 | [diff] [blame] | 393 | return dentry->d_flags & DCACHE_MOUNTED; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 394 | } |
| 395 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 396 | extern int sysctl_vfs_cache_pressure; |
| 397 | |
Glauber Costa | 55f841c | 2013-08-28 10:17:53 +1000 | [diff] [blame] | 398 | static inline unsigned long vfs_pressure_ratio(unsigned long val) |
| 399 | { |
| 400 | return mult_frac(val, sysctl_vfs_cache_pressure, 100); |
| 401 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 402 | #endif /* __LINUX_DCACHE_H */ |