[PATCH trivial] include/linux/dcache.h: Cleanup code and comments
From: chengang
Date: Sat Jan 09 2016 - 07:34:06 EST
From: Chen Gang <chengang@xxxxxxxxxxxxxxxx>
Notice about 80 columns.
Notice about the the comments format.
Remove useless lines and variables.
Signed-off-by: Chen Gang <gang.chen.5i5j@xxxxxxxxx>
---
include/linux/dcache.h | 204 +++++++++++++++++++++++++------------------------
1 file changed, 104 insertions(+), 100 deletions(-)
diff --git a/include/linux/dcache.h b/include/linux/dcache.h
index 7781ce11..b468ec7 100644
--- a/include/linux/dcache.h
+++ b/include/linux/dcache.h
@@ -38,7 +38,7 @@ struct vfsmount;
* "quick string" -- eases parameter passing, but more importantly
* saves "metadata" about the string (ie length and the hash).
*
- * hash comes first so it snuggles against d_parent in the
+ * Hash comes first so it snuggles against d_parent in the
* dentry.
*/
struct qstr {
@@ -59,17 +59,19 @@ struct qstr {
struct dentry_stat_t {
long nr_dentry;
long nr_unused;
- long age_limit; /* age in seconds */
- long want_pages; /* pages requested by system */
+ long age_limit; /* Age in seconds */
+ long want_pages; /* Pages requested by system */
long dummy[2];
};
extern struct dentry_stat_t dentry_stat;
-/* Name hashing routines. Initial hash value */
-/* Hash courtesy of the R5 hash in reiserfs modulo sign bits */
+/*
+ * Name hashing routines. Initial hash value.
+ * Hash courtesy of the R5 hash in reiserfs modulo sign bits
+ */
#define init_name_hash() 0
-/* partial hash update function. Assume roughly 4 bits per character */
+/* Partial hash update function. Assume roughly 4 bits per character */
static inline unsigned long
partial_name_hash(unsigned long c, unsigned long prevhash)
{
@@ -107,30 +109,29 @@ extern unsigned int full_name_hash(const unsigned char *, unsigned int);
struct dentry {
/* RCU lookup touched fields */
- unsigned int d_flags; /* protected by d_lock */
- seqcount_t d_seq; /* per dentry seqlock */
- struct hlist_bl_node d_hash; /* lookup hash list */
- struct dentry *d_parent; /* parent directory */
+ unsigned int d_flags; /* Protected by d_lock */
+ seqcount_t d_seq; /* Per dentry seqlock */
+ struct hlist_bl_node d_hash; /* Lookup hash list */
+ struct dentry *d_parent; /* Parent directory */
struct qstr d_name;
struct inode *d_inode; /* Where the name belongs to - NULL is
- * negative */
- unsigned char d_iname[DNAME_INLINE_LEN]; /* small names */
+ * negative
+ */
+ unsigned char d_iname[DNAME_INLINE_LEN]; /* Small names */
/* Ref lookup also touches following */
- struct lockref d_lockref; /* per-dentry lock and refcount */
+ struct lockref d_lockref; /* Per-dentry lock and refcount */
const struct dentry_operations *d_op;
struct super_block *d_sb; /* The root of the dentry tree */
- unsigned long d_time; /* used by d_revalidate */
- void *d_fsdata; /* fs-specific data */
+ unsigned long d_time; /* Used by d_revalidate */
+ void *d_fsdata; /* Fs-specific data */
struct list_head d_lru; /* LRU list */
- struct list_head d_child; /* child of parent list */
- struct list_head d_subdirs; /* our children */
- /*
- * d_alias and d_rcu can share memory
- */
+ struct list_head d_child; /* Child of parent list */
+ struct list_head d_subdirs; /* Our children */
+ /* d_alias and d_rcu can share memory */
union {
- struct hlist_node d_alias; /* inode alias list */
+ struct hlist_node d_alias; /* Inode alias list */
struct rcu_head d_rcu;
} d_u;
};
@@ -143,7 +144,7 @@ struct dentry {
*/
enum dentry_d_lock_class
{
- DENTRY_D_LOCK_NORMAL, /* implicitly used by plain spin_lock() APIs. */
+ DENTRY_D_LOCK_NORMAL, /* Implicitly used by plain spin_lock() APIs. */
DENTRY_D_LOCK_NESTED
};
@@ -167,7 +168,7 @@ struct dentry_operations {
* Locking rules for dentry_operations callbacks are to be found in
* Documentation/filesystems/Locking. Keep it updated!
*
- * FUrther descriptions are found in Documentation/filesystems/vfs.txt.
+ * Further descriptions are found in Documentation/filesystems/vfs.txt.
* Keep it updated too!
*/
@@ -177,73 +178,84 @@ struct dentry_operations {
#define DCACHE_OP_REVALIDATE 0x00000004
#define DCACHE_OP_DELETE 0x00000008
#define DCACHE_OP_PRUNE 0x00000010
-
+/*
+ * This dentry is possibly not currently connected to the dcache tree, in which
+ * case its parent will either be itself, or will have this flag as well. nfsd
+ * will not use a dentry with this bit set, but will first endeavour to clear
+ * the bit either by discovering that it is connected, or by performing lookup
+ * operations. Any filesystem which supports nfsd_operations MUST have a lookup
+ * function which, if it finds a directory inode with a DCACHE_DISCONNECTED
+ * dentry, will d_move that dentry into place and return that dentry rather than
+ * the passed one typically using d_splice_alias.
+ */
#define DCACHE_DISCONNECTED 0x00000020
- /* This dentry is possibly not currently connected to the dcache tree, in
- * which case its parent will either be itself, or will have this flag as
- * well. nfsd will not use a dentry with this bit set, but will first
- * endeavour to clear the bit either by discovering that it is connected,
- * or by performing lookup operations. Any filesystem which supports
- * nfsd_operations MUST have a lookup function which, if it finds a
- * directory inode with a DCACHE_DISCONNECTED dentry, will d_move that
- * dentry into place and return that dentry rather than the passed one,
- * typically using d_splice_alias. */
-
-#define DCACHE_REFERENCED 0x00000040 /* Recently used, don't discard. */
-#define DCACHE_RCUACCESS 0x00000080 /* Entry has ever been RCU-visible */
-
+/* Recently used, don't discard. */
+#define DCACHE_REFERENCED 0x00000040
+/* Entry has ever been RCU-visible */
+#define DCACHE_RCUACCESS 0x00000080
#define DCACHE_CANT_MOUNT 0x00000100
#define DCACHE_GENOCIDE 0x00000200
#define DCACHE_SHRINK_LIST 0x00000400
-
#define DCACHE_OP_WEAK_REVALIDATE 0x00000800
-
+/*
+ * This dentry has been "silly renamed" and has to be deleted on the
+ * last dput()
+ */
#define DCACHE_NFSFS_RENAMED 0x00001000
- /* this dentry has been "silly renamed" and has to be deleted on the last
- * dput() */
-#define DCACHE_COOKIE 0x00002000 /* For use by dcookie subsystem */
+/* For use by dcookie subsystem */
+#define DCACHE_COOKIE 0x00002000
+/* Parent inode is watched by some fsnotify listener */
#define DCACHE_FSNOTIFY_PARENT_WATCHED 0x00004000
- /* Parent inode is watched by some fsnotify listener */
-
#define DCACHE_DENTRY_KILLED 0x00008000
-
-#define DCACHE_MOUNTED 0x00010000 /* is a mountpoint */
-#define DCACHE_NEED_AUTOMOUNT 0x00020000 /* handle automount on this dir */
-#define DCACHE_MANAGE_TRANSIT 0x00040000 /* manage transit from this dirent */
+/* Is a mountpoint */
+#define DCACHE_MOUNTED 0x00010000
+/* Handle automount on this dir */
+#define DCACHE_NEED_AUTOMOUNT 0x00020000
+/* Manage transit from this dirent */
+#define DCACHE_MANAGE_TRANSIT 0x00040000
#define DCACHE_MANAGED_DENTRY \
(DCACHE_MOUNTED|DCACHE_NEED_AUTOMOUNT|DCACHE_MANAGE_TRANSIT)
#define DCACHE_LRU_LIST 0x00080000
#define DCACHE_ENTRY_TYPE 0x00700000
-#define DCACHE_MISS_TYPE 0x00000000 /* Negative dentry (maybe fallthru to nowhere) */
-#define DCACHE_WHITEOUT_TYPE 0x00100000 /* Whiteout dentry (stop pathwalk) */
-#define DCACHE_DIRECTORY_TYPE 0x00200000 /* Normal directory */
-#define DCACHE_AUTODIR_TYPE 0x00300000 /* Lookupless directory (presumed automount) */
-#define DCACHE_REGULAR_TYPE 0x00400000 /* Regular file type (or fallthru to such) */
-#define DCACHE_SPECIAL_TYPE 0x00500000 /* Other file type (or fallthru to such) */
-#define DCACHE_SYMLINK_TYPE 0x00600000 /* Symlink (or fallthru to such) */
+/* Negative dentry (maybe fallthru to nowhere) */
+#define DCACHE_MISS_TYPE 0x00000000
+/* Whiteout dentry (stop pathwalk) */
+#define DCACHE_WHITEOUT_TYPE 0x00100000
+/* Normal directory */
+#define DCACHE_DIRECTORY_TYPE 0x00200000
+/* Lookupless directory (presumed automount) */
+#define DCACHE_AUTODIR_TYPE 0x00300000
+/* Regular file type (or fallthru to such) */
+#define DCACHE_REGULAR_TYPE 0x00400000
+/* Other file type (or fallthru to such) */
+#define DCACHE_SPECIAL_TYPE 0x00500000
+/* Symlink (or fallthru to such) */
+#define DCACHE_SYMLINK_TYPE 0x00600000
#define DCACHE_MAY_FREE 0x00800000
-#define DCACHE_FALLTHRU 0x01000000 /* Fall through to lower layer */
-#define DCACHE_OP_SELECT_INODE 0x02000000 /* Unioned entry: dcache op selects inode */
+/* Fall through to lower layer */
+#define DCACHE_FALLTHRU 0x01000000
+/* Unioned entry: dcache op selects inode */
+#define DCACHE_OP_SELECT_INODE 0x02000000
extern seqlock_t rename_lock;
-/*
- * These are the low-level FS interfaces to the dcache..
- */
+/* These are the low-level FS interfaces to the dcache. */
extern void d_instantiate(struct dentry *, struct inode *);
extern struct dentry * d_instantiate_unique(struct dentry *, struct inode *);
extern int d_instantiate_no_diralias(struct dentry *, struct inode *);
extern void __d_drop(struct dentry *dentry);
extern void d_drop(struct dentry *dentry);
extern void d_delete(struct dentry *);
-extern void d_set_d_op(struct dentry *dentry, const struct dentry_operations *op);
+extern void d_set_d_op(struct dentry *dentry,
+ const struct dentry_operations *op);
-/* allocate/de-allocate */
+/* Allocate/de-allocate */
extern struct dentry * d_alloc(struct dentry *, const struct qstr *);
-extern struct dentry * d_alloc_pseudo(struct super_block *, const struct qstr *);
+extern struct dentry *d_alloc_pseudo(struct super_block *,
+ const struct qstr *);
extern struct dentry * d_splice_alias(struct inode *, struct dentry *);
extern struct dentry * d_add_ci(struct dentry *, struct inode *, struct qstr *);
extern struct dentry *d_find_any_alias(struct inode *inode);
@@ -254,7 +266,7 @@ extern void shrink_dcache_parent(struct dentry *);
extern void shrink_dcache_for_umount(struct super_block *);
extern void d_invalidate(struct dentry *);
-/* only used at mount-time */
+/* Only used at mount-time */
extern struct dentry * d_make_root(struct inode *);
/* <clickety>-<click> the ramfs-type tree */
@@ -265,15 +277,13 @@ extern void d_tmpfile(struct dentry *, struct inode *);
extern struct dentry *d_find_alias(struct inode *);
extern void d_prune_aliases(struct inode *);
-/* test whether we have any submounts in a subdir tree */
+/* Test whether we have any submounts in a subdir tree */
extern int have_submounts(struct dentry *);
-/*
- * This adds the entry to the hash queues.
- */
+/* This adds the entry to the hash queues. */
extern void d_rehash(struct dentry *);
-/**
+/*
* d_add - add dentry to hash queues
* @entry: dentry to add
* @inode: The inode to attach to this dentry
@@ -281,14 +291,13 @@ extern void d_rehash(struct dentry *);
* This adds the entry to the hash queues and initializes @inode.
* The entry was actually filled in earlier during d_alloc().
*/
-
static inline void d_add(struct dentry *entry, struct inode *inode)
{
d_instantiate(entry, inode);
d_rehash(entry);
}
-/**
+/*
* d_add_unique - add dentry to hash queues without aliasing
* @entry: dentry to add
* @inode: The inode to attach to this dentry
@@ -296,23 +305,23 @@ static inline void d_add(struct dentry *entry, struct inode *inode)
* This adds the entry to the hash queues and initializes @inode.
* The entry was actually filled in earlier during d_alloc().
*/
-static inline struct dentry *d_add_unique(struct dentry *entry, struct inode *inode)
+static inline struct dentry *d_add_unique(struct dentry *entry,
+ struct inode *inode)
{
- struct dentry *res;
+ struct dentry *res = d_instantiate_unique(entry, inode);
- res = d_instantiate_unique(entry, inode);
d_rehash(res != NULL ? res : entry);
return res;
}
extern void dentry_update_name_case(struct dentry *, struct qstr *);
-/* used for rename() and baskets */
+/* Used for rename() and baskets */
extern void d_move(struct dentry *, struct dentry *);
extern void d_exchange(struct dentry *, struct dentry *);
extern struct dentry *d_ancestor(struct dentry *, struct dentry *);
-/* appendix may either be NULL or be used for transname suffixes */
+/* Appendix may either be NULL or be used for transname suffixes */
extern struct dentry *d_lookup(const struct dentry *, const struct qstr *);
extern struct dentry *d_hash_and_lookup(struct dentry *, struct qstr *);
extern struct dentry *__d_lookup(const struct dentry *, const struct qstr *);
@@ -324,9 +333,7 @@ static inline unsigned d_count(const struct dentry *dentry)
return dentry->d_lockref.count;
}
-/*
- * helper function for dentry_operations.d_dname() members
- */
+/* Helper function for dentry_operations.d_dname() members */
extern __printf(4, 5)
char *dynamic_dname(struct dentry *, char *, int, const char *, ...);
extern char *simple_dname(struct dentry *, char *, int);
@@ -339,8 +346,8 @@ extern char *dentry_path(struct dentry *, char *, int);
/* Allocation counts.. */
-/**
- * dget, dget_dlock - get a reference to a dentry
+/*
+ * dget, dget_dlock - get a reference to a dentry
* @dentry: dentry to get a reference to
*
* Given a dentry or %NULL pointer increment the reference count
@@ -363,8 +370,8 @@ static inline struct dentry *dget(struct dentry *dentry)
extern struct dentry *dget_parent(struct dentry *dentry);
-/**
- * d_unhashed - is dentry hashed
+/*
+ * d_unhashed - is dentry hashed
* @dentry: entry to check
*
* Returns true if the dentry passed is not currently hashed.
@@ -404,9 +411,7 @@ static inline bool d_mountpoint(const struct dentry *dentry)
return dentry->d_flags & DCACHE_MOUNTED;
}
-/*
- * Directory cache entry type accessor functions.
- */
+/* Directory cache entry type accessor functions. */
static inline unsigned __d_entry_type(const struct dentry *dentry)
{
unsigned type = READ_ONCE(dentry->d_flags);
@@ -461,7 +466,7 @@ static inline bool d_is_file(const struct dentry *dentry)
static inline bool d_is_negative(const struct dentry *dentry)
{
- // TODO: check d_is_whiteout(dentry) also.
+ /* TODO: check d_is_whiteout(dentry) also. */
return d_is_miss(dentry);
}
@@ -470,8 +475,9 @@ static inline bool d_is_positive(const struct dentry *dentry)
return !d_is_negative(dentry);
}
-/**
- * d_really_is_negative - Determine if a dentry is really negative (ignoring fallthroughs)
+/*
+ * d_really_is_negative - Determine if a dentry is really negative (ignoring
+ * fallthroughs)
* @dentry: The dentry in question
*
* Returns true if the dentry represents either an absent name or a name that
@@ -490,8 +496,9 @@ static inline bool d_really_is_negative(const struct dentry *dentry)
return dentry->d_inode == NULL;
}
-/**
- * d_really_is_positive - Determine if a dentry is really positive (ignoring fallthroughs)
+/*
+ * d_really_is_positive - Determine if a dentry is really positive (ignoring
+ * fallthroughs)
* @dentry: The dentry in question
*
* Returns true if the dentry represents a name that maps to an inode
@@ -508,7 +515,7 @@ static inline bool d_really_is_positive(const struct dentry *dentry)
return dentry->d_inode != NULL;
}
-static inline int simple_positive(struct dentry *dentry)
+static inline bool simple_positive(struct dentry *dentry)
{
return d_really_is_positive(dentry) && !d_unhashed(dentry);
}
@@ -520,7 +527,6 @@ static inline bool d_is_fallthru(const struct dentry *dentry)
return dentry->d_flags & DCACHE_FALLTHRU;
}
-
extern int sysctl_vfs_cache_pressure;
static inline unsigned long vfs_pressure_ratio(unsigned long val)
@@ -528,7 +534,7 @@ static inline unsigned long vfs_pressure_ratio(unsigned long val)
return mult_frac(val, sysctl_vfs_cache_pressure, 100);
}
-/**
+/*
* d_inode - Get the actual inode of this dentry
* @dentry: The dentry to query
*
@@ -540,7 +546,7 @@ static inline struct inode *d_inode(const struct dentry *dentry)
return dentry->d_inode;
}
-/**
+/*
* d_inode_rcu - Get the actual inode of this dentry with ACCESS_ONCE()
* @dentry: The dentry to query
*
@@ -552,7 +558,7 @@ static inline struct inode *d_inode_rcu(const struct dentry *dentry)
return ACCESS_ONCE(dentry->d_inode);
}
-/**
+/*
* d_backing_inode - Get upper or lower inode we should be using
* @upper: The upper layer
*
@@ -564,12 +570,10 @@ static inline struct inode *d_inode_rcu(const struct dentry *dentry)
*/
static inline struct inode *d_backing_inode(const struct dentry *upper)
{
- struct inode *inode = upper->d_inode;
-
- return inode;
+ return upper->d_inode;
}
-/**
+/*
* d_backing_dentry - Get upper or lower dentry we should be using
* @upper: The upper layer
*
--
1.9.3