NFS: Clean up the write request locking.
Ensure that we set/clear NFS_PAGE_TAG_LOCKED when the nfs_page is hashed.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c
index 345bb9b..3b3dbb9 100644
--- a/fs/nfs/pagelist.c
+++ b/fs/nfs/pagelist.c
@@ -111,13 +111,14 @@
* nfs_set_page_tag_locked - Tag a request as locked
* @req:
*/
-static int nfs_set_page_tag_locked(struct nfs_page *req)
+int nfs_set_page_tag_locked(struct nfs_page *req)
{
struct nfs_inode *nfsi = NFS_I(req->wb_context->path.dentry->d_inode);
- if (!nfs_lock_request(req))
+ if (!nfs_lock_request_dontget(req))
return 0;
- radix_tree_tag_set(&nfsi->nfs_page_tree, req->wb_index, NFS_PAGE_TAG_LOCKED);
+ if (req->wb_page != NULL)
+ radix_tree_tag_set(&nfsi->nfs_page_tree, req->wb_index, NFS_PAGE_TAG_LOCKED);
return 1;
}
@@ -132,9 +133,10 @@
if (req->wb_page != NULL) {
spin_lock(&inode->i_lock);
radix_tree_tag_clear(&nfsi->nfs_page_tree, req->wb_index, NFS_PAGE_TAG_LOCKED);
+ nfs_unlock_request(req);
spin_unlock(&inode->i_lock);
- }
- nfs_unlock_request(req);
+ } else
+ nfs_unlock_request(req);
}
/**
@@ -421,6 +423,7 @@
goto out;
idx_start = req->wb_index + 1;
if (nfs_set_page_tag_locked(req)) {
+ kref_get(&req->wb_kref);
nfs_list_remove_request(req);
radix_tree_tag_clear(&nfsi->nfs_page_tree,
req->wb_index, tag);
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 51cc1bd..092e79c 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -196,7 +196,7 @@
}
/* Update file length */
nfs_grow_file(page, offset, count);
- nfs_unlock_request(req);
+ nfs_clear_page_tag_locked(req);
return 0;
}
@@ -252,7 +252,6 @@
struct page *page)
{
struct inode *inode = page->mapping->host;
- struct nfs_inode *nfsi = NFS_I(inode);
struct nfs_page *req;
int ret;
@@ -263,10 +262,10 @@
spin_unlock(&inode->i_lock);
return 0;
}
- if (nfs_lock_request_dontget(req))
+ if (nfs_set_page_tag_locked(req))
break;
/* Note: If we hold the page lock, as is the case in nfs_writepage,
- * then the call to nfs_lock_request_dontget() will always
+ * then the call to nfs_set_page_tag_locked() will always
* succeed provided that someone hasn't already marked the
* request as dirty (in which case we don't care).
*/
@@ -280,7 +279,7 @@
if (test_bit(PG_NEED_COMMIT, &req->wb_flags)) {
/* This request is marked for commit */
spin_unlock(&inode->i_lock);
- nfs_unlock_request(req);
+ nfs_clear_page_tag_locked(req);
nfs_pageio_complete(pgio);
return 0;
}
@@ -288,8 +287,6 @@
spin_unlock(&inode->i_lock);
BUG();
}
- radix_tree_tag_set(&nfsi->nfs_page_tree, req->wb_index,
- NFS_PAGE_TAG_LOCKED);
spin_unlock(&inode->i_lock);
nfs_pageio_add_request(pgio, req);
return 0;
@@ -381,6 +378,7 @@
set_page_private(req->wb_page, (unsigned long)req);
nfsi->npages++;
kref_get(&req->wb_kref);
+ radix_tree_tag_set(&nfsi->nfs_page_tree, req->wb_index, NFS_PAGE_TAG_LOCKED);
return 0;
}
@@ -596,7 +594,7 @@
spin_lock(&inode->i_lock);
req = nfs_page_find_request_locked(page);
if (req) {
- if (!nfs_lock_request_dontget(req)) {
+ if (!nfs_set_page_tag_locked(req)) {
int error;
spin_unlock(&inode->i_lock);
@@ -646,7 +644,7 @@
|| req->wb_page != page
|| !nfs_dirty_request(req)
|| offset > rqend || end < req->wb_offset) {
- nfs_unlock_request(req);
+ nfs_clear_page_tag_locked(req);
return ERR_PTR(-EBUSY);
}
diff --git a/include/linux/nfs_page.h b/include/linux/nfs_page.h
index 30dbcc1..a1676e1 100644
--- a/include/linux/nfs_page.h
+++ b/include/linux/nfs_page.h
@@ -83,6 +83,7 @@
extern void nfs_pageio_cond_complete(struct nfs_pageio_descriptor *, pgoff_t);
extern int nfs_wait_on_request(struct nfs_page *);
extern void nfs_unlock_request(struct nfs_page *req);
+extern int nfs_set_page_tag_locked(struct nfs_page *req);
extern void nfs_clear_page_tag_locked(struct nfs_page *req);
@@ -95,18 +96,6 @@
return !test_and_set_bit(PG_BUSY, &req->wb_flags);
}
-/*
- * Lock the page of an asynchronous request and take a reference
- */
-static inline int
-nfs_lock_request(struct nfs_page *req)
-{
- if (test_and_set_bit(PG_BUSY, &req->wb_flags))
- return 0;
- kref_get(&req->wb_kref);
- return 1;
-}
-
/**
* nfs_list_add_request - Insert a request into a list
* @req: request