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authorMike Marshall <hubcap@omnibond.com>2015-07-17 16:38:12 +0200
committerMike Marshall <hubcap@omnibond.com>2015-10-03 17:39:54 +0200
commit5db11c21a929cd9d8c0484006efb1014fc723c93 (patch)
tree014b77a693c2b33c4558903e325ec0a2e9c0ebf6 /fs/orangefs/dcache.c
parentOrangefs: kernel client part 1 (diff)
downloadlinux-5db11c21a929cd9d8c0484006efb1014fc723c93.tar.xz
linux-5db11c21a929cd9d8c0484006efb1014fc723c93.zip
Orangefs: kernel client part 2
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Diffstat (limited to 'fs/orangefs/dcache.c')
-rw-r--r--fs/orangefs/dcache.c142
1 files changed, 142 insertions, 0 deletions
diff --git a/fs/orangefs/dcache.c b/fs/orangefs/dcache.c
new file mode 100644
index 000000000000..9466b179bf24
--- /dev/null
+++ b/fs/orangefs/dcache.c
@@ -0,0 +1,142 @@
+/*
+ * (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,
+};