NFS: Clean up the write request locking. (acee478a) · Commits · e / devices / android_kernel_fairphone_FP3

fs/nfs/pagelist.c

+8 −5

Original line number	Original line	Diff line number	Diff line
	@@ -111,12 +111,13 @@ void nfs_unlock_request(struct nfs_page *req)
	* nfs_set_page_tag_locked - Tag a request as locked		* nfs_set_page_tag_locked - Tag a request as locked
	* @req:		* @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);		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;		return 0;
			if (req->wb_page != NULL)
	radix_tree_tag_set(&nfsi->nfs_page_tree, req->wb_index, NFS_PAGE_TAG_LOCKED);		radix_tree_tag_set(&nfsi->nfs_page_tree, req->wb_index, NFS_PAGE_TAG_LOCKED);
	return 1;		return 1;
	}		}
	@@ -132,8 +133,9 @@ void nfs_clear_page_tag_locked(struct nfs_page *req)
	if (req->wb_page != NULL) {		if (req->wb_page != NULL) {
	spin_lock(&inode->i_lock);		spin_lock(&inode->i_lock);
	radix_tree_tag_clear(&nfsi->nfs_page_tree, req->wb_index, NFS_PAGE_TAG_LOCKED);		radix_tree_tag_clear(&nfsi->nfs_page_tree, req->wb_index, NFS_PAGE_TAG_LOCKED);
			nfs_unlock_request(req);
	spin_unlock(&inode->i_lock);		spin_unlock(&inode->i_lock);
	}		} else
	nfs_unlock_request(req);		nfs_unlock_request(req);
	}		}

	@@ -421,6 +423,7 @@ int nfs_scan_list(struct nfs_inode *nfsi,
	goto out;		goto out;
	idx_start = req->wb_index + 1;		idx_start = req->wb_index + 1;
	if (nfs_set_page_tag_locked(req)) {		if (nfs_set_page_tag_locked(req)) {
			kref_get(&req->wb_kref);
	nfs_list_remove_request(req);		nfs_list_remove_request(req);
	radix_tree_tag_clear(&nfsi->nfs_page_tree,		radix_tree_tag_clear(&nfsi->nfs_page_tree,
	req->wb_index, tag);		req->wb_index, tag);

fs/nfs/write.c

+7 −9

Original line number	Original line	Diff line number	Diff line
	@@ -196,7 +196,7 @@ static int nfs_writepage_setup(struct nfs_open_context ctx, struct page page,
	}		}
	/* Update file length */		/* Update file length */
	nfs_grow_file(page, offset, count);		nfs_grow_file(page, offset, count);
	nfs_unlock_request(req);		nfs_clear_page_tag_locked(req);
	return 0;		return 0;
	}		}

	@@ -252,7 +252,6 @@ static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio,
	struct page *page)		struct page *page)
	{		{
	struct inode *inode = page->mapping->host;		struct inode *inode = page->mapping->host;
	struct nfs_inode *nfsi = NFS_I(inode);
	struct nfs_page *req;		struct nfs_page *req;
	int ret;		int ret;

	@@ -263,10 +262,10 @@ static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio,
	spin_unlock(&inode->i_lock);		spin_unlock(&inode->i_lock);
	return 0;		return 0;
	}		}
	if (nfs_lock_request_dontget(req))		if (nfs_set_page_tag_locked(req))
	break;		break;
	/* Note: If we hold the page lock, as is the case in nfs_writepage,		/* 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		* succeed provided that someone hasn't already marked the
	* request as dirty (in which case we don't care).		* request as dirty (in which case we don't care).
	*/		*/
	@@ -280,7 +279,7 @@ static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio,
	if (test_bit(PG_NEED_COMMIT, &req->wb_flags)) {		if (test_bit(PG_NEED_COMMIT, &req->wb_flags)) {
	/* This request is marked for commit */		/* This request is marked for commit */
	spin_unlock(&inode->i_lock);		spin_unlock(&inode->i_lock);
	nfs_unlock_request(req);		nfs_clear_page_tag_locked(req);
	nfs_pageio_complete(pgio);		nfs_pageio_complete(pgio);
	return 0;		return 0;
	}		}
	@@ -288,8 +287,6 @@ static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio,
	spin_unlock(&inode->i_lock);		spin_unlock(&inode->i_lock);
	BUG();		BUG();
	}		}
	radix_tree_tag_set(&nfsi->nfs_page_tree, req->wb_index,
	NFS_PAGE_TAG_LOCKED);
	spin_unlock(&inode->i_lock);		spin_unlock(&inode->i_lock);
	nfs_pageio_add_request(pgio, req);		nfs_pageio_add_request(pgio, req);
	return 0;		return 0;
	@@ -381,6 +378,7 @@ static int nfs_inode_add_request(struct inode inode, struct nfs_page req)
	set_page_private(req->wb_page, (unsigned long)req);		set_page_private(req->wb_page, (unsigned long)req);
	nfsi->npages++;		nfsi->npages++;
	kref_get(&req->wb_kref);		kref_get(&req->wb_kref);
			radix_tree_tag_set(&nfsi->nfs_page_tree, req->wb_index, NFS_PAGE_TAG_LOCKED);
	return 0;		return 0;
	}		}

	@@ -596,7 +594,7 @@ static struct nfs_page * nfs_update_request(struct nfs_open_context* ctx,
	spin_lock(&inode->i_lock);		spin_lock(&inode->i_lock);
	req = nfs_page_find_request_locked(page);		req = nfs_page_find_request_locked(page);
	if (req) {		if (req) {
	if (!nfs_lock_request_dontget(req)) {		if (!nfs_set_page_tag_locked(req)) {
	int error;		int error;

	spin_unlock(&inode->i_lock);		spin_unlock(&inode->i_lock);
	@@ -646,7 +644,7 @@ static struct nfs_page * nfs_update_request(struct nfs_open_context* ctx,
	\|\| req->wb_page != page		\|\| req->wb_page != page
	\|\| !nfs_dirty_request(req)		\|\| !nfs_dirty_request(req)
	\|\| offset > rqend \|\| end < req->wb_offset) {		\|\| offset > rqend \|\| end < req->wb_offset) {
	nfs_unlock_request(req);		nfs_clear_page_tag_locked(req);
	return ERR_PTR(-EBUSY);		return ERR_PTR(-EBUSY);
	}		}

include/linux/nfs_page.h

+1 −12

Original line number	Original line	Diff line number	Diff line
	@@ -83,6 +83,7 @@ extern void nfs_pageio_complete(struct nfs_pageio_descriptor *desc);
	extern void nfs_pageio_cond_complete(struct nfs_pageio_descriptor *, pgoff_t);		extern void nfs_pageio_cond_complete(struct nfs_pageio_descriptor *, pgoff_t);
	extern int nfs_wait_on_request(struct nfs_page *);		extern int nfs_wait_on_request(struct nfs_page *);
	extern void nfs_unlock_request(struct nfs_page *req);		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);		extern void nfs_clear_page_tag_locked(struct nfs_page *req);


	@@ -95,18 +96,6 @@ nfs_lock_request_dontget(struct nfs_page *req)
	return !test_and_set_bit(PG_BUSY, &req->wb_flags);		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		* nfs_list_add_request - Insert a request into a list
	* @req: request		* @req: request