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[PATCH] knfsd: lockd: make nlm_traverse_* more flexible

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This patch makes nlm_traverse{locks,blocks,shares} and friends use a function
pointer rather than a "action" enum.

This function pointer is given two nlm_hosts (one given by the caller, the
other taken from the lock/block/share currently visited), and is free to do
with them as it wants.  If it returns a non-zero value, the lockd/block/share
is released.

Signed-off-by: Olaf Kirch <okir@suse.de>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Olaf Kirch
2006-10-04 02:15:59 -07:00
committed by Linus Torvalds
parent 07ba806351
commit f2af793db0
5 changed files with 103 additions and 75 deletions
Download Patch File Download Diff File Expand all files Collapse all files
fs/lockd/svcsubs.c
+78 -29
View File
@@ -165,7 +165,8 @@ nlm_delete_file(struct nlm_file *file)
* action.
*/
static int
nlm_traverse_locks(struct nlm_host *host, struct nlm_file *file, int action)
nlm_traverse_locks(struct nlm_host *host, struct nlm_file *file,
nlm_host_match_fn_t match)
{
struct inode *inode = nlmsvc_file_inode(file);
struct file_lock *fl;
@@ -179,16 +180,10 @@ again:
/* update current lock count */
file->f_locks++;
lockhost = (struct nlm_host *) fl->fl_owner;
if (action == NLM_ACT_MARK)
lockhost->h_inuse = 1;
else if (action == NLM_ACT_CHECK)
return 1;
else if (action == NLM_ACT_UNLOCK) {
struct file_lock lock = *fl;
if (host && lockhost != host)
continue;
lockhost = (struct nlm_host *) fl->fl_owner;
if (match(lockhost, host)) {
struct file_lock lock = *fl;
lock.fl_type = F_UNLCK;
lock.fl_start = 0;
@@ -206,27 +201,42 @@ again:
}
/*
* Operate on a single file
* Inspect a single file
*/
static inline int
nlm_inspect_file(struct nlm_host *host, struct nlm_file *file, int action)
nlm_inspect_file(struct nlm_host *host, struct nlm_file *file, nlm_host_match_fn_t match)
{
if (action == NLM_ACT_CHECK) {
/* Fast path for mark and sweep garbage collection */
if (file->f_count || list_empty(&file->f_blocks) || file->f_shares)
nlmsvc_traverse_blocks(host, file, match);
nlmsvc_traverse_shares(host, file, match);
return nlm_traverse_locks(host, file, match);
}
/*
* Quick check whether there are still any locks, blocks or
* shares on a given file.
*/
static inline int
nlm_file_inuse(struct nlm_file *file)
{
struct inode *inode = nlmsvc_file_inode(file);
struct file_lock *fl;
if (file->f_count || !list_empty(&file->f_blocks) || file->f_shares)
return 1;
for (fl = inode->i_flock; fl; fl = fl->fl_next) {
if (fl->fl_lmops == &nlmsvc_lock_operations)
return 1;
} else {
nlmsvc_traverse_blocks(host, file, action);
nlmsvc_traverse_shares(host, file, action);
}
return nlm_traverse_locks(host, file, action);
file->f_locks = 0;
return 0;
}
/*
* Loop over all files in the file table.
*/
static int
nlm_traverse_files(struct nlm_host *host, int action)
nlm_traverse_files(struct nlm_host *host, nlm_host_match_fn_t match)
{
struct hlist_node *pos, *next;
struct nlm_file *file;
@@ -240,7 +250,7 @@ nlm_traverse_files(struct nlm_host *host, int action)
/* Traverse locks, blocks and shares of this file
* and update file->f_locks count */
if (nlm_inspect_file(host, file, action))
if (nlm_inspect_file(host, file, match))
ret = 1;
mutex_lock(&nlm_file_mutex);
@@ -277,14 +287,46 @@ nlm_release_file(struct nlm_file *file)
mutex_lock(&nlm_file_mutex);
/* If there are no more locks etc, delete the file */
if(--file->f_count == 0) {
if(!nlm_inspect_file(NULL, file, NLM_ACT_CHECK))
nlm_delete_file(file);
}
if (--file->f_count == 0 && !nlm_file_inuse(file))
nlm_delete_file(file);
mutex_unlock(&nlm_file_mutex);
}
/*
* Helpers function for resource traversal
*
* nlmsvc_mark_host:
* used by the garbage collector; simply sets h_inuse.
* Always returns 0.
*
* nlmsvc_same_host:
* returns 1 iff the two hosts match. Used to release
* all resources bound to a specific host.
*
* nlmsvc_is_client:
* returns 1 iff the host is a client.
* Used by nlmsvc_invalidate_all
*/
static int
nlmsvc_mark_host(struct nlm_host *host, struct nlm_host *dummy)
{
host->h_inuse = 1;
return 0;
}
static int
nlmsvc_same_host(struct nlm_host *host, struct nlm_host *other)
{
return host == other;
}
static int
nlmsvc_is_client(struct nlm_host *host, struct nlm_host *dummy)
{
return host->h_server;
}
/*
* Mark all hosts that still hold resources
*/
@@ -292,8 +334,7 @@ void
nlmsvc_mark_resources(void)
{
dprintk("lockd: nlmsvc_mark_resources\n");
nlm_traverse_files(NULL, NLM_ACT_MARK);
nlm_traverse_files(NULL, nlmsvc_mark_host);
}
/*
@@ -304,7 +345,7 @@ nlmsvc_free_host_resources(struct nlm_host *host)
{
dprintk("lockd: nlmsvc_free_host_resources\n");
if (nlm_traverse_files(host, NLM_ACT_UNLOCK)) {
if (nlm_traverse_files(host, nlmsvc_same_host)) {
printk(KERN_WARNING
"lockd: couldn't remove all locks held by %s\n",
host->h_name);
@@ -319,8 +360,16 @@ void
nlmsvc_invalidate_all(void)
{
struct nlm_host *host;
/* Release all locks held by NFS clients.
* Previously, the code would call
* nlmsvc_free_host_resources for each client in
* turn, which is about as inefficient as it gets.
* Now we just do it once in nlm_traverse_files.
*/
nlm_traverse_files(NULL, nlmsvc_is_client);
while ((host = nlm_find_client()) != NULL) {
nlmsvc_free_host_resources(host);
host->h_expires = 0;
host->h_killed = 1;
nlm_release_host(host);