142 lines
3.5 KiB
C
142 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 "pvfs2-kernel.h"
|
|
|
|
/* Returns 1 if dentry can still be trusted, else 0. */
|
|
static int pvfs2_revalidate_lookup(struct dentry *dentry)
|
|
{
|
|
struct dentry *parent_dentry = dget_parent(dentry);
|
|
struct inode *parent_inode = parent_dentry->d_inode;
|
|
struct pvfs2_inode_s *parent = PVFS2_I(parent_inode);
|
|
struct inode *inode = dentry->d_inode;
|
|
struct pvfs2_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(PVFS2_VFS_OP_LOOKUP);
|
|
if (!new_op)
|
|
goto out_put_parent;
|
|
|
|
new_op->upcall.req.lookup.sym_follow = PVFS2_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,
|
|
PVFS2_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, "pvfs2_lookup",
|
|
get_interruptible_flag(parent_inode));
|
|
if (err)
|
|
goto out_drop;
|
|
|
|
if (new_op->downcall.status != 0 ||
|
|
!match_handle(new_op->downcall.resp.lookup.refn.khandle, inode)) {
|
|
gossip_debug(GOSSIP_DCACHE_DEBUG,
|
|
"%s:%s:%d "
|
|
"lookup failure |%s| or no match |%s|.\n",
|
|
__FILE__,
|
|
__func__,
|
|
__LINE__,
|
|
new_op->downcall.status ? "true" : "false",
|
|
match_handle(new_op->downcall.resp.lookup.refn.khandle,
|
|
inode) ? "false" : "true");
|
|
gossip_debug(GOSSIP_DCACHE_DEBUG,
|
|
"%s:%s:%d revalidate failed\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:
|
|
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 pvfs2_d_revalidate(struct dentry *dentry, unsigned int flags)
|
|
{
|
|
struct inode *inode;
|
|
int ret = 0;
|
|
|
|
if (flags & LOOKUP_RCU)
|
|
return -ECHILD;
|
|
|
|
gossip_debug(GOSSIP_DCACHE_DEBUG, "%s: called on dentry %p.\n",
|
|
__func__, dentry);
|
|
|
|
/* find inode from dentry */
|
|
if (!dentry->d_inode) {
|
|
gossip_debug(GOSSIP_DCACHE_DEBUG, "%s: negative dentry.\n",
|
|
__func__);
|
|
goto invalid_exit;
|
|
}
|
|
|
|
gossip_debug(GOSSIP_DCACHE_DEBUG, "%s: inode valid.\n", __func__);
|
|
inode = dentry->d_inode;
|
|
|
|
/*
|
|
* first perform a lookup to make sure that the object not only
|
|
* exists, but is still in the expected place in the name space
|
|
*/
|
|
if (!is_root_handle(inode)) {
|
|
if (!pvfs2_revalidate_lookup(dentry))
|
|
goto invalid_exit;
|
|
} else {
|
|
gossip_debug(GOSSIP_DCACHE_DEBUG,
|
|
"%s: root handle, lookup skipped.\n",
|
|
__func__);
|
|
}
|
|
|
|
/* now perform getattr */
|
|
gossip_debug(GOSSIP_DCACHE_DEBUG,
|
|
"%s: doing getattr: inode: %p, handle: %pU\n",
|
|
__func__,
|
|
inode,
|
|
get_khandle_from_ino(inode));
|
|
ret = pvfs2_inode_getattr(inode, PVFS_ATTR_SYS_ALL_NOHINT);
|
|
gossip_debug(GOSSIP_DCACHE_DEBUG,
|
|
"%s: getattr %s (ret = %d), returning %s for dentry i_count=%d\n",
|
|
__func__,
|
|
(ret == 0 ? "succeeded" : "failed"),
|
|
ret,
|
|
(ret == 0 ? "valid" : "INVALID"),
|
|
atomic_read(&inode->i_count));
|
|
if (ret != 0)
|
|
goto invalid_exit;
|
|
|
|
/* dentry is valid! */
|
|
return 1;
|
|
|
|
invalid_exit:
|
|
return 0;
|
|
}
|
|
|
|
const struct dentry_operations pvfs2_dentry_operations = {
|
|
.d_revalidate = pvfs2_d_revalidate,
|
|
};
|