fs: change d_compare for rcu-walk

Change d_compare so it may be called from lock-free RCU lookups. This
does put significant restrictions on what may be done from the callback,
however there don't seem to have been any problems with in-tree fses.
If some strange use case pops up that _really_ cannot cope with the
rcu-walk rules, we can just add new rcu-unaware callbacks, which would
cause name lookup to drop out of rcu-walk mode.

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

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
This commit is contained in:
Nick Piggin
2011-01-07 17:49:27 +11:00
parent fb2d5b86af
commit 621e155a35
23 changed files with 242 additions and 157 deletions

View File

@ -92,21 +92,21 @@ int hfs_strcmp(const unsigned char *s1, unsigned int len1,
* Test for equality of two strings in the HFS filename character ordering.
* return 1 on failure and 0 on success
*/
int hfs_compare_dentry(struct dentry *dentry, struct qstr *s1, struct qstr *s2)
int hfs_compare_dentry(const struct dentry *parent, const struct inode *pinode,
const struct dentry *dentry, const struct inode *inode,
unsigned int len, const char *str, const struct qstr *name)
{
const unsigned char *n1, *n2;
int len;
len = s1->len;
if (len >= HFS_NAMELEN) {
if (s2->len < HFS_NAMELEN)
if (name->len < HFS_NAMELEN)
return 1;
len = HFS_NAMELEN;
} else if (len != s2->len)
} else if (len != name->len)
return 1;
n1 = s1->name;
n2 = s2->name;
n1 = str;
n2 = name->name;
while (len--) {
if (caseorder[*n1++] != caseorder[*n2++])
return 1;