Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit b1e6a015 authored by Nick Piggin's avatar Nick Piggin
Browse files

fs: change d_hash for rcu-walk 



Change d_hash so it may be called from lock-free RCU lookups. See similar
patch for d_compare for details.

For in-tree filesystems, this is just a mechanical change.

Signed-off-by: default avatarNick Piggin <npiggin@kernel.dk>
parent 621e155a

Documentation/filesystems/Locking

+3 −2
Original line number Diff line number Diff line
@@ -10,7 +10,8 @@ be able to use diff(1). 
--------------------------- dentry_operations --------------------------

prototypes:

	int (*d_revalidate)(struct dentry *, int);

	int (*d_hash) (struct dentry *, struct qstr *);

	int (*d_hash)(const struct dentry *, const struct inode *,

			struct qstr *);

	int (*d_compare)(const struct dentry *, const struct inode *,

			const struct dentry *, const struct inode *,

			unsigned int, const char *, const struct qstr *);
@@ -22,7 +23,7 @@ prototypes: 
locking rules:

		dcache_lock	rename_lock	->d_lock	may block

d_revalidate:	no		no		no		yes

d_hash		no		no		no		yes

d_hash		no		no		no		no

d_compare:	no		yes		no		no 

d_delete:	yes		no		yes		no

d_release:	no		no		no		yes

Documentation/filesystems/porting

+7 −0
Original line number Diff line number Diff line
@@ -333,3 +333,10 @@ unreferenced dentries, and is now only called when the dentry refcount goes to 
	.d_compare() calling convention and locking rules are significantly

changed. Read updated documentation in Documentation/filesystems/vfs.txt (and

look at examples of other filesystems) for guidance.



---

[mandatory]



	.d_hash() calling convention and locking rules are significantly

changed. Read updated documentation in Documentation/filesystems/vfs.txt (and

look at examples of other filesystems) for guidance.

Documentation/filesystems/vfs.txt

+6 −2
Original line number Diff line number Diff line
@@ -847,7 +847,8 @@ defined: 


struct dentry_operations {

	int (*d_revalidate)(struct dentry *, struct nameidata *);

	int (*d_hash)(struct dentry *, struct qstr *);

	int (*d_hash)(const struct dentry *, const struct inode *,

			struct qstr *);

	int (*d_compare)(const struct dentry *, const struct inode *,

			const struct dentry *, const struct inode *,

			unsigned int, const char *, const struct qstr *);
@@ -864,7 +865,10 @@ struct dentry_operations { 


  d_hash: called when the VFS adds a dentry to the hash table. The first

	dentry passed to d_hash is the parent directory that the name is

	to be hashed into.

	to be hashed into. The inode is the dentry's inode.



	Same locking and synchronisation rules as d_compare regarding

	what is safe to dereference etc.



  d_compare: called to compare a dentry name with a given name. The first

	dentry is the parent of the dentry to be compared, the second is

drivers/staging/smbfs/cache.c

+1 −1
Original line number Diff line number Diff line
@@ -134,7 +134,7 @@ smb_fill_cache(struct file *filp, void *dirent, filldir_t filldir, 
	qname->hash = full_name_hash(qname->name, qname->len);



	if (dentry->d_op && dentry->d_op->d_hash)

		if (dentry->d_op->d_hash(dentry, qname) != 0)

		if (dentry->d_op->d_hash(dentry, inode, qname) != 0)

			goto end_advance;



	newdent = d_lookup(dentry, qname);

drivers/staging/smbfs/dir.c

+4 −2
Original line number Diff line number Diff line
@@ -274,7 +274,8 @@ smb_dir_open(struct inode *dir, struct file *file) 
 * Dentry operations routines

 */

static int smb_lookup_validate(struct dentry *, struct nameidata *);

static int smb_hash_dentry(struct dentry *, struct qstr *);

static int smb_hash_dentry(const struct dentry *, const struct inode *,

		struct qstr *);

static int smb_compare_dentry(const struct dentry *,

		const struct inode *,

		const struct dentry *, const struct inode *,
@@ -336,7 +337,8 @@ smb_lookup_validate(struct dentry * dentry, struct nameidata *nd) 
}



static int 

smb_hash_dentry(struct dentry *dir, struct qstr *this)

smb_hash_dentry(const struct dentry *dir, const struct inode *inode,

		struct qstr *this)

{

	unsigned long hash;

	int i;