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author | Mike Marshall <hubcap@omnibond.com> | 2015-07-17 16:38:12 +0200 |
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committer | Mike Marshall <hubcap@omnibond.com> | 2015-10-03 17:39:54 +0200 |
commit | 5db11c21a929cd9d8c0484006efb1014fc723c93 (patch) | |
tree | 014b77a693c2b33c4558903e325ec0a2e9c0ebf6 /fs/orangefs/dcache.c | |
parent | Orangefs: kernel client part 1 (diff) | |
download | linux-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.c | 142 |
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, +}; |