NFSv4: Ensure that we track the NFSv4 lock state in read/write requests.
This patch fixes bugzilla entry 14501:
https://bugzilla.kernel.org/show_bug.cgi?id=14501
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 099b351..ec7a8f9 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -530,6 +530,68 @@
return err;
}
+static void nfs_init_lock_context(struct nfs_lock_context *l_ctx)
+{
+ atomic_set(&l_ctx->count, 1);
+ l_ctx->lockowner = current->files;
+ l_ctx->pid = current->tgid;
+ INIT_LIST_HEAD(&l_ctx->list);
+}
+
+static struct nfs_lock_context *__nfs_find_lock_context(struct nfs_open_context *ctx)
+{
+ struct nfs_lock_context *pos;
+
+ list_for_each_entry(pos, &ctx->lock_context.list, list) {
+ if (pos->lockowner != current->files)
+ continue;
+ if (pos->pid != current->tgid)
+ continue;
+ atomic_inc(&pos->count);
+ return pos;
+ }
+ return NULL;
+}
+
+struct nfs_lock_context *nfs_get_lock_context(struct nfs_open_context *ctx)
+{
+ struct nfs_lock_context *res, *new = NULL;
+ struct inode *inode = ctx->path.dentry->d_inode;
+
+ spin_lock(&inode->i_lock);
+ res = __nfs_find_lock_context(ctx);
+ if (res == NULL) {
+ spin_unlock(&inode->i_lock);
+ new = kmalloc(sizeof(*new), GFP_KERNEL);
+ if (new == NULL)
+ return NULL;
+ nfs_init_lock_context(new);
+ spin_lock(&inode->i_lock);
+ res = __nfs_find_lock_context(ctx);
+ if (res == NULL) {
+ list_add_tail(&new->list, &ctx->lock_context.list);
+ new->open_context = ctx;
+ res = new;
+ new = NULL;
+ }
+ }
+ spin_unlock(&inode->i_lock);
+ kfree(new);
+ return res;
+}
+
+void nfs_put_lock_context(struct nfs_lock_context *l_ctx)
+{
+ struct nfs_open_context *ctx = l_ctx->open_context;
+ struct inode *inode = ctx->path.dentry->d_inode;
+
+ if (!atomic_dec_and_lock(&l_ctx->count, &inode->i_lock))
+ return;
+ list_del(&l_ctx->list);
+ spin_unlock(&inode->i_lock);
+ kfree(l_ctx);
+}
+
/**
* nfs_close_context - Common close_context() routine NFSv2/v3
* @ctx: pointer to context
@@ -566,11 +628,11 @@
path_get(&ctx->path);
ctx->cred = get_rpccred(cred);
ctx->state = NULL;
- ctx->lockowner = current->files;
ctx->flags = 0;
ctx->error = 0;
ctx->dir_cookie = 0;
- atomic_set(&ctx->count, 1);
+ nfs_init_lock_context(&ctx->lock_context);
+ ctx->lock_context.open_context = ctx;
}
return ctx;
}
@@ -578,7 +640,7 @@
struct nfs_open_context *get_nfs_open_context(struct nfs_open_context *ctx)
{
if (ctx != NULL)
- atomic_inc(&ctx->count);
+ atomic_inc(&ctx->lock_context.count);
return ctx;
}
@@ -586,7 +648,7 @@
{
struct inode *inode = ctx->path.dentry->d_inode;
- if (!atomic_dec_and_lock(&ctx->count, &inode->i_lock))
+ if (!atomic_dec_and_lock(&ctx->lock_context.count, &inode->i_lock))
return;
list_del(&ctx->list);
spin_unlock(&inode->i_lock);