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Diffstat (limited to 'fs/lockd/svcsubs.c')
-rw-r--r--fs/lockd/svcsubs.c141
1 files changed, 99 insertions, 42 deletions
diff --git a/fs/lockd/svcsubs.c b/fs/lockd/svcsubs.c
index 344e6c187cde..ffab76278bb2 100644
--- a/fs/lockd/svcsubs.c
+++ b/fs/lockd/svcsubs.c
@@ -17,7 +17,6 @@
#include <linux/sunrpc/addr.h>
#include <linux/module.h>
#include <linux/mount.h>
-#include <uapi/linux/nfs2.h>
#include "lockd.h"
#include "share.h"
@@ -67,7 +66,7 @@ static inline unsigned int file_hash(struct nfs_fh *f)
{
unsigned int tmp=0;
int i;
- for (i=0; i<NFS2_FHSIZE;i++)
+ for (i = 0; i < LOCKD_FH_HASH_SIZE; i++)
tmp += f->data[i];
return tmp & (FILE_NRHASH - 1);
}
@@ -83,23 +82,49 @@ int lock_to_openmode(struct file_lock *lock)
*
* We have to make sure we have the right credential to open
* the file.
+ *
+ * @mode is O_RDONLY, O_WRONLY, or O_RDWR. O_RDWR means success
+ * is achieved with EITHER O_RDONLY or O_WRONLY; it does not
+ * require both.
*/
static __be32 nlm_do_fopen(struct svc_rqst *rqstp,
struct nlm_file *file, int mode)
{
- struct file **fp = &file->f_file[mode];
- __be32 nlmerr = nlm_granted;
+ const struct nlmsvc_binding *ops;
+ __be32 nlmerr = nlm__int__failed;
+ __be32 deferred = 0;
int error;
+ int m;
+
+ rcu_read_lock();
+ ops = rcu_dereference(nlmsvc_ops);
+ if (!ops || !try_module_get(ops->owner)) {
+ rcu_read_unlock();
+ return nlm__int__failed;
+ }
+ rcu_read_unlock();
+
+ for (m = O_RDONLY; m <= O_WRONLY; m++) {
+ struct file **fp = &file->f_file[m];
- if (*fp)
- return nlmerr;
+ if (mode != O_RDWR && mode != m)
+ continue;
+ if (*fp) {
+ module_put(ops->owner);
+ return nlm_granted;
+ }
+
+ error = ops->fopen(rqstp, &file->f_handle, fp, m);
+ if (!error) {
+ module_put(ops->owner);
+ return nlm_granted;
+ }
- error = nlmsvc_ops->fopen(rqstp, &file->f_handle, fp, mode);
- if (error) {
dprintk("lockd: open failed (errno %d)\n", error);
switch (error) {
case -EWOULDBLOCK:
nlmerr = nlm__int__drop_reply;
+ deferred = nlmerr;
break;
case -ESTALE:
nlmerr = nlm__int__stale_fh;
@@ -110,7 +135,8 @@ static __be32 nlm_do_fopen(struct svc_rqst *rqstp,
}
}
- return nlmerr;
+ module_put(ops->owner);
+ return deferred ? deferred : nlmerr;
}
/*
@@ -119,17 +145,15 @@ static __be32 nlm_do_fopen(struct svc_rqst *rqstp,
*/
__be32
nlm_lookup_file(struct svc_rqst *rqstp, struct nlm_file **result,
- struct nlm_lock *lock)
+ struct lockd_lock *lock, int mode)
{
struct nlm_file *file;
unsigned int hash;
__be32 nfserr;
- int mode;
nlm_debug_print_fh("nlm_lookup_file", &lock->fh);
hash = file_hash(&lock->fh);
- mode = lock_to_openmode(&lock->fl);
/* Lock file table */
mutex_lock(&nlm_file_mutex);
@@ -139,6 +163,8 @@ nlm_lookup_file(struct svc_rqst *rqstp, struct nlm_file **result,
mutex_lock(&file->f_mutex);
nfserr = nlm_do_fopen(rqstp, file, mode);
mutex_unlock(&file->f_mutex);
+ if (nfserr)
+ goto out_unlock;
goto found;
}
nlm_debug_print_fh("creating file for", &lock->fh);
@@ -155,7 +181,7 @@ nlm_lookup_file(struct svc_rqst *rqstp, struct nlm_file **result,
nfserr = nlm_do_fopen(rqstp, file, mode);
if (nfserr)
- goto out_unlock;
+ goto out_free;
hlist_add_head(&file->f_list, &nlm_files[hash]);
@@ -174,6 +200,33 @@ out_free:
}
/*
+ * Release the struct file references held by a nlm_file.
+ */
+static void nlm_release_files(struct nlm_file *file)
+{
+ const struct nlmsvc_binding *ops;
+ bool have_ops;
+
+ rcu_read_lock();
+ ops = rcu_dereference(nlmsvc_ops);
+ have_ops = ops && try_module_get(ops->owner);
+ rcu_read_unlock();
+
+ if (have_ops) {
+ if (file->f_file[O_RDONLY])
+ ops->fclose(file->f_file[O_RDONLY]);
+ if (file->f_file[O_WRONLY])
+ ops->fclose(file->f_file[O_WRONLY]);
+ module_put(ops->owner);
+ } else {
+ if (file->f_file[O_RDONLY])
+ fput(file->f_file[O_RDONLY]);
+ if (file->f_file[O_WRONLY])
+ fput(file->f_file[O_WRONLY]);
+ }
+}
+
+/*
* Delete a file after having released all locks, blocks and shares
*/
static inline void
@@ -182,10 +235,7 @@ nlm_delete_file(struct nlm_file *file)
nlm_debug_print_file("closing file", file);
if (!hlist_unhashed(&file->f_list)) {
hlist_del(&file->f_list);
- if (file->f_file[O_RDONLY])
- nlmsvc_ops->fclose(file->f_file[O_RDONLY]);
- if (file->f_file[O_WRONLY])
- nlmsvc_ops->fclose(file->f_file[O_WRONLY]);
+ nlm_release_files(file);
kfree(file);
} else {
printk(KERN_WARNING "lockd: attempt to release unknown file!\n");
@@ -300,12 +350,10 @@ nlm_file_inuse(struct nlm_file *file)
return 0;
}
-static void nlm_close_files(struct nlm_file *file)
+static void nlm_file_release(struct nlm_file *file)
{
- if (file->f_file[O_RDONLY])
- nlmsvc_ops->fclose(file->f_file[O_RDONLY]);
- if (file->f_file[O_WRONLY])
- nlmsvc_ops->fclose(file->f_file[O_WRONLY]);
+ if (!nlm_file_inuse(file))
+ nlm_delete_file(file);
}
/*
@@ -315,32 +363,41 @@ static int
nlm_traverse_files(void *data, nlm_host_match_fn_t match,
int (*is_failover_file)(void *data, struct nlm_file *file))
{
- struct hlist_node *next;
- struct nlm_file *file;
+ struct nlm_file *file, *next;
int i, ret = 0;
mutex_lock(&nlm_file_mutex);
for (i = 0; i < FILE_NRHASH; i++) {
- hlist_for_each_entry_safe(file, next, &nlm_files[i], f_list) {
- if (is_failover_file && !is_failover_file(data, file))
- continue;
+ file = hlist_entry_safe(nlm_files[i].first,
+ struct nlm_file, f_list);
+ if (file)
file->f_count++;
- mutex_unlock(&nlm_file_mutex);
-
- /* Traverse locks, blocks and shares of this file
- * and update file->f_locks count */
- if (nlm_inspect_file(data, file, match))
- ret = 1;
+ while (file) {
+ /*
+ * Pin the next neighbour before we drop the mutex
+ * for nlm_inspect_file(); a concurrent
+ * nlm_release_file() under the same mutex would
+ * otherwise be free to unlink and kfree it during
+ * the unlock window, leaving us to dereference a
+ * freed slab when we walked to next afterwards.
+ */
+ next = hlist_entry_safe(file->f_list.next,
+ struct nlm_file, f_list);
+ if (next)
+ next->f_count++;
+
+ if (!is_failover_file || is_failover_file(data, file)) {
+ mutex_unlock(&nlm_file_mutex);
+
+ if (nlm_inspect_file(data, file, match))
+ ret = 1;
+
+ mutex_lock(&nlm_file_mutex);
+ }
- mutex_lock(&nlm_file_mutex);
file->f_count--;
- /* No more references to this file. Let go of it. */
- if (list_empty(&file->f_blocks) && !file->f_locks
- && !file->f_shares && !file->f_count) {
- hlist_del(&file->f_list);
- nlm_close_files(file);
- kfree(file);
- }
+ nlm_file_release(file);
+ file = next;
}
}
mutex_unlock(&nlm_file_mutex);
@@ -500,7 +557,7 @@ EXPORT_SYMBOL_GPL(nlmsvc_unlock_all_by_sb);
static int
nlmsvc_match_ip(void *datap, struct nlm_host *host)
{
- return rpc_cmp_addr(nlm_srcaddr(host), datap);
+ return rpc_cmp_addr(nlm_srcaddr(datap), (struct sockaddr *)host);
}
/**
generated by cgit v1.2.3 (git 2.0.4) at 2026-09-25 23:28:13 +0000