+++ /dev/null
-From: ffilz@us.ibm.com
-Subject: Revert "NFS: Allow redirtying of a completed unstable write."
-Patch-mainline: REVERT patch from 2.6.27
-References: 442267
-
-mainline commit e468bae97d243fe0e1515abaa1f7d0edf1476ad0
-introduces a BUG() that is apprently fairly easy to trigger.
-As it is just making a minor performance enhancement, it is best to
-revert the patch until the issue is better understood.
-
-Acked-by: NeilBrown <neilb@suse.de>
-Signed-off-by: Neil Brown <neilb@suse.de>
-
----
- fs/nfs/write.c | 65 ++++++++++++++++++++++++++++-----------------------------
- 1 file changed, 33 insertions(+), 32 deletions(-)
-
---- a/fs/nfs/write.c
-+++ b/fs/nfs/write.c
-@@ -284,9 +284,12 @@ static int nfs_page_async_flush(struct n
- return ret;
- spin_lock(&inode->i_lock);
- }
-- if (test_bit(PG_CLEAN, &req->wb_flags)) {
-+ if (test_bit(PG_NEED_COMMIT, &req->wb_flags)) {
-+ /* This request is marked for commit */
- spin_unlock(&inode->i_lock);
-- BUG();
-+ nfs_clear_page_tag_locked(req);
-+ nfs_pageio_complete(pgio);
-+ return 0;
- }
- if (nfs_set_page_writeback(page) != 0) {
- spin_unlock(&inode->i_lock);
-@@ -460,6 +463,19 @@ nfs_mark_request_dirty(struct nfs_page *
- __set_page_dirty_nobuffers(req->wb_page);
- }
-
-+/*
-+ * Check if a request is dirty
-+ */
-+static inline int
-+nfs_dirty_request(struct nfs_page *req)
-+{
-+ struct page *page = req->wb_page;
-+
-+ if (page == NULL || test_bit(PG_NEED_COMMIT, &req->wb_flags))
-+ return 0;
-+ return !PageWriteback(page);
-+}
-+
- #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
- /*
- * Add a request to the inode's commit list.
-@@ -472,7 +488,7 @@ nfs_mark_request_commit(struct nfs_page
-
- spin_lock(&inode->i_lock);
- nfsi->ncommit++;
-- set_bit(PG_CLEAN, &(req)->wb_flags);
-+ set_bit(PG_NEED_COMMIT, &(req)->wb_flags);
- radix_tree_tag_set(&nfsi->nfs_page_tree,
- req->wb_index,
- NFS_PAGE_TAG_COMMIT);
-@@ -483,19 +499,6 @@ nfs_mark_request_commit(struct nfs_page
- __mark_inode_dirty(inode, I_DIRTY_DATASYNC);
- }
-
--static int
--nfs_clear_request_commit(struct nfs_page *req)
--{
-- struct page *page = req->wb_page;
--
-- if (test_and_clear_bit(PG_CLEAN, &(req)->wb_flags)) {
-- dec_zone_page_state(page, NR_UNSTABLE_NFS);
-- dec_bdi_stat(page_file_mapping(page)->backing_dev_info, BDI_RECLAIMABLE);
-- return 1;
-- }
-- return 0;
--}
--
- static inline
- int nfs_write_need_commit(struct nfs_write_data *data)
- {
-@@ -505,7 +508,7 @@ int nfs_write_need_commit(struct nfs_wri
- static inline
- int nfs_reschedule_unstable_write(struct nfs_page *req)
- {
-- if (test_and_clear_bit(PG_NEED_COMMIT, &req->wb_flags)) {
-+ if (test_bit(PG_NEED_COMMIT, &req->wb_flags)) {
- nfs_mark_request_commit(req);
- return 1;
- }
-@@ -521,12 +524,6 @@ nfs_mark_request_commit(struct nfs_page
- {
- }
-
--static inline int
--nfs_clear_request_commit(struct nfs_page *req)
--{
-- return 0;
--}
--
- static inline
- int nfs_write_need_commit(struct nfs_write_data *data)
- {
-@@ -584,8 +581,11 @@ static void nfs_cancel_commit_list(struc
-
- while(!list_empty(head)) {
- req = nfs_list_entry(head->next);
-+ dec_zone_page_state(req->wb_page, NR_UNSTABLE_NFS);
-+ dec_bdi_stat(req->wb_page->mapping->backing_dev_info,
-+ BDI_RECLAIMABLE);
- nfs_list_remove_request(req);
-- nfs_clear_request_commit(req);
-+ clear_bit(PG_NEED_COMMIT, &(req)->wb_flags);
- nfs_inode_remove_request(req);
- nfs_unlock_request(req);
- }
-@@ -657,7 +657,8 @@ static struct nfs_page *nfs_try_to_updat
- * Note: nfs_flush_incompatible() will already
- * have flushed out requests having wrong owners.
- */
-- if (offset > rqend
-+ if (!nfs_dirty_request(req)
-+ || offset > rqend
- || end < req->wb_offset)
- goto out_flushme;
-
-@@ -673,10 +674,6 @@ static struct nfs_page *nfs_try_to_updat
- spin_lock(&inode->i_lock);
- }
-
-- if (nfs_clear_request_commit(req))
-- radix_tree_tag_clear(&NFS_I(inode)->nfs_page_tree,
-- req->wb_index, NFS_PAGE_TAG_COMMIT);
--
- /* Okay, the request matches. Update the region */
- if (offset < req->wb_offset) {
- req->wb_offset = offset;
-@@ -758,7 +755,8 @@ int nfs_flush_incompatible(struct file *
- req = nfs_page_find_request(page);
- if (req == NULL)
- return 0;
-- do_flush = req->wb_page != page || req->wb_context != ctx;
-+ do_flush = req->wb_page != page || req->wb_context != ctx
-+ || !nfs_dirty_request(req);
- nfs_release_request(req);
- if (!do_flush)
- return 0;
-@@ -1363,7 +1361,10 @@ static void nfs_commit_release(void *cal
- while (!list_empty(&data->pages)) {
- req = nfs_list_entry(data->pages.next);
- nfs_list_remove_request(req);
-- nfs_clear_request_commit(req);
-+ clear_bit(PG_NEED_COMMIT, &(req)->wb_flags);
-+ dec_zone_page_state(req->wb_page, NR_UNSTABLE_NFS);
-+ dec_bdi_stat(req->wb_page->mapping->backing_dev_info,
-+ BDI_RECLAIMABLE);
-
- dprintk("NFS: commit (%s/%lld %d@%lld)",
- req->wb_context->path.dentry->d_inode->i_sb->s_id,
-@@ -1539,7 +1540,7 @@ int nfs_wb_page_cancel(struct inode *ino
- req = nfs_page_find_request(page);
- if (req == NULL)
- goto out;
-- if (test_bit(PG_CLEAN, &req->wb_flags)) {
-+ if (test_bit(PG_NEED_COMMIT, &req->wb_flags)) {
- nfs_release_request(req);
- break;
- }
projects / ipfire-2.x.git / blobdiff