Commit 0145acc2 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

vfs: uninline full_name_hash() 



.. and also use it in lookup_one_len() rather than open-coding it.

There aren't any performance-critical users, so inlining it is silly.
But it wouldn't matter if it wasn't for the fact that the word-at-a-time
dentry name patches want to conditionally replace the function, and
uninlining it sets the stage for that.

So again, this is a preparatory patch that doesn't change any semantics,
and only prepares for a much cleaner and testable word-at-a-time dentry
name accessor patch.

Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 8966be90

fs/namei.c

+9 −4
Original line number Diff line number Diff line
@@ -1374,6 +1374,14 @@ static inline int can_lookup(struct inode *inode) 
	return 1;

}



unsigned int full_name_hash(const unsigned char *name, unsigned int len)

{

	unsigned long hash = init_name_hash();

	while (len--)

		hash = partial_name_hash(*name++, hash);

	return end_name_hash(hash);

}



/*

 * Name resolution.

 * This is the basic name resolution function, turning a pathname into
@@ -1775,24 +1783,21 @@ static struct dentry *lookup_hash(struct nameidata *nd) 
struct dentry *lookup_one_len(const char *name, struct dentry *base, int len)

{

	struct qstr this;

	unsigned long hash;

	unsigned int c;



	WARN_ON_ONCE(!mutex_is_locked(&base->d_inode->i_mutex));



	this.name = name;

	this.len = len;

	this.hash = full_name_hash(name, len);

	if (!len)

		return ERR_PTR(-EACCES);



	hash = init_name_hash();

	while (len--) {

		c = *(const unsigned char *)name++;

		if (c == '/' || c == '\0')

			return ERR_PTR(-EACCES);

		hash = partial_name_hash(c, hash);

	}

	this.hash = end_name_hash(hash);

	/*

	 * See if the low-level filesystem might want

	 * to use its own hash..

include/linux/dcache.h

+1 −8
Original line number Diff line number Diff line
@@ -89,14 +89,7 @@ static inline unsigned long end_name_hash(unsigned long hash) 
}



/* Compute the hash for a name string. */

static inline unsigned int

full_name_hash(const unsigned char *name, unsigned int len)

{

	unsigned long hash = init_name_hash();

	while (len--)

		hash = partial_name_hash(*name++, hash);

	return end_name_hash(hash);

}

extern unsigned int full_name_hash(const unsigned char *, unsigned int);



/*

 * Try to keep struct dentry aligned on 64 byte cachelines (this will

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