forked from Minki/linux
99109822f5
Previously, it would update a live inode. This was fixed, but it did not ever check that the inode attributes in the dcache are correct. This checks all inode attributes and rejects any that are not correct, which causes a lookup and thus a new getattr. Perhaps inode_operations->permission should replace or augment some of this. There is no actual caching, and this does a rather excessive amount of network operations back to the filesystem server. Signed-off-by: Martin Brandenburg <martin@omnibond.com> Signed-off-by: Mike Marshall <hubcap@omnibond.com>
145 lines
3.5 KiB
C
145 lines
3.5 KiB
C
/*
|
|
* (C) 2001 Clemson University and The University of Chicago
|
|
*
|
|
* See COPYING in top-level directory.
|
|
*/
|
|
|
|
/*
|
|
* Implementation of dentry (directory cache) functions.
|
|
*/
|
|
|
|
#include "protocol.h"
|
|
#include "orangefs-kernel.h"
|
|
|
|
/* Returns 1 if dentry can still be trusted, else 0. */
|
|
static int orangefs_revalidate_lookup(struct dentry *dentry)
|
|
{
|
|
struct dentry *parent_dentry = dget_parent(dentry);
|
|
struct inode *parent_inode = parent_dentry->d_inode;
|
|
struct orangefs_inode_s *parent = ORANGEFS_I(parent_inode);
|
|
struct inode *inode = dentry->d_inode;
|
|
struct orangefs_kernel_op_s *new_op;
|
|
int ret = 0;
|
|
int err = 0;
|
|
|
|
gossip_debug(GOSSIP_DCACHE_DEBUG, "%s: attempting lookup.\n", __func__);
|
|
|
|
new_op = op_alloc(ORANGEFS_VFS_OP_LOOKUP);
|
|
if (!new_op)
|
|
goto out_put_parent;
|
|
|
|
new_op->upcall.req.lookup.sym_follow = ORANGEFS_LOOKUP_LINK_NO_FOLLOW;
|
|
new_op->upcall.req.lookup.parent_refn = parent->refn;
|
|
strncpy(new_op->upcall.req.lookup.d_name,
|
|
dentry->d_name.name,
|
|
ORANGEFS_NAME_LEN);
|
|
|
|
gossip_debug(GOSSIP_DCACHE_DEBUG,
|
|
"%s:%s:%d interrupt flag [%d]\n",
|
|
__FILE__,
|
|
__func__,
|
|
__LINE__,
|
|
get_interruptible_flag(parent_inode));
|
|
|
|
err = service_operation(new_op, "orangefs_lookup",
|
|
get_interruptible_flag(parent_inode));
|
|
|
|
/* Positive dentry: reject if error or not the same inode. */
|
|
if (inode) {
|
|
if (err) {
|
|
gossip_debug(GOSSIP_DCACHE_DEBUG,
|
|
"%s:%s:%d lookup failure.\n",
|
|
__FILE__, __func__, __LINE__);
|
|
goto out_drop;
|
|
}
|
|
if (!match_handle(new_op->downcall.resp.lookup.refn.khandle,
|
|
inode)) {
|
|
gossip_debug(GOSSIP_DCACHE_DEBUG,
|
|
"%s:%s:%d no match.\n",
|
|
__FILE__, __func__, __LINE__);
|
|
goto out_drop;
|
|
}
|
|
|
|
/* Negative dentry: reject if success or error other than ENOENT. */
|
|
} else {
|
|
gossip_debug(GOSSIP_DCACHE_DEBUG, "%s: negative dentry.\n",
|
|
__func__);
|
|
if (!err || err != -ENOENT) {
|
|
if (new_op->downcall.status != 0)
|
|
gossip_debug(GOSSIP_DCACHE_DEBUG,
|
|
"%s:%s:%d lookup failure.\n",
|
|
__FILE__, __func__, __LINE__);
|
|
goto out_drop;
|
|
}
|
|
}
|
|
|
|
ret = 1;
|
|
out_release_op:
|
|
op_release(new_op);
|
|
out_put_parent:
|
|
dput(parent_dentry);
|
|
return ret;
|
|
out_drop:
|
|
gossip_debug(GOSSIP_DCACHE_DEBUG, "%s:%s:%d revalidate failed\n",
|
|
__FILE__, __func__, __LINE__);
|
|
d_drop(dentry);
|
|
goto out_release_op;
|
|
}
|
|
|
|
/*
|
|
* Verify that dentry is valid.
|
|
*
|
|
* Should return 1 if dentry can still be trusted, else 0.
|
|
*/
|
|
static int orangefs_d_revalidate(struct dentry *dentry, unsigned int flags)
|
|
{
|
|
int ret;
|
|
|
|
if (flags & LOOKUP_RCU)
|
|
return -ECHILD;
|
|
|
|
gossip_debug(GOSSIP_DCACHE_DEBUG, "%s: called on dentry %p.\n",
|
|
__func__, dentry);
|
|
|
|
/* skip root handle lookups. */
|
|
if (dentry->d_inode && is_root_handle(dentry->d_inode))
|
|
return 1;
|
|
|
|
/*
|
|
* If this passes, the positive dentry still exists or the negative
|
|
* dentry still does not exist.
|
|
*/
|
|
if (!orangefs_revalidate_lookup(dentry)) {
|
|
d_drop(dentry);
|
|
return 0;
|
|
}
|
|
|
|
/* We do not need to continue with negative dentries. */
|
|
if (!dentry->d_inode)
|
|
goto out;
|
|
|
|
/* Now we must perform a getattr to validate the inode contents. */
|
|
ret = orangefs_inode_getattr(dentry->d_inode,
|
|
ORANGEFS_ATTR_SYS_ALL_NOHINT, 1);
|
|
if (ret < 0) {
|
|
gossip_debug(GOSSIP_DCACHE_DEBUG, "%s:%s:%d getattr failure.\n",
|
|
__FILE__, __func__, __LINE__);
|
|
d_drop(dentry);
|
|
return 0;
|
|
}
|
|
if (ret == 0) {
|
|
d_drop(dentry);
|
|
return 0;
|
|
}
|
|
|
|
out:
|
|
gossip_debug(GOSSIP_DCACHE_DEBUG,
|
|
"%s: negative dentry or positive dentry and inode valid.\n",
|
|
__func__);
|
|
return 1;
|
|
}
|
|
|
|
const struct dentry_operations orangefs_dentry_operations = {
|
|
.d_revalidate = orangefs_d_revalidate,
|
|
};
|