diff options
| -rw-r--r-- | fs/nfs/blocklayout/blocklayout.c | 78 |
1 files changed, 54 insertions, 24 deletions
diff --git a/fs/nfs/blocklayout/blocklayout.c b/fs/nfs/blocklayout/blocklayout.c index a263810803c..23427362185 100644 --- a/fs/nfs/blocklayout/blocklayout.c +++ b/fs/nfs/blocklayout/blocklayout.c @@ -490,6 +490,55 @@ cleanup: return ret; } +/* Find or create a zeroing page marked being writeback. + * Return ERR_PTR on error, NULL to indicate skip this page and page itself + * to indicate write out. + */ +static struct page * +bl_find_get_zeroing_page(struct inode *inode, pgoff_t index, + struct pnfs_block_extent *cow_read) +{ + struct page *page; + int locked = 0; + page = find_get_page(inode->i_mapping, index); + if (page) + goto check_page; + + page = find_or_create_page(inode->i_mapping, index, GFP_NOFS); + if (unlikely(!page)) { + dprintk("%s oom\n", __func__); + return ERR_PTR(-ENOMEM); + } + locked = 1; + +check_page: + /* PageDirty: Other will write this out + * PageWriteback: Other is writing this out + * PageUptodate: It was read before + */ + if (PageDirty(page) || PageWriteback(page)) { + print_page(page); + if (locked) + unlock_page(page); + page_cache_release(page); + return NULL; + } + + if (!locked) { + lock_page(page); + locked = 1; + goto check_page; + } + if (!PageUptodate(page)) { + /* New page, readin or zero it */ + init_page_for_write(page, cow_read); + } + set_page_writeback(page); + unlock_page(page); + + return page; +} + static enum pnfs_try_status bl_write_pagelist(struct nfs_write_data *wdata, int sync) { @@ -549,32 +598,13 @@ fill_invalid_ext: dprintk("%s zero %dth page: index %lu isect %llu\n", __func__, npg_zero, index, (unsigned long long)isect); - page = - find_or_create_page(wdata->inode->i_mapping, index, - GFP_NOFS); - if (!page) { - dprintk("%s oom\n", __func__); - wdata->pnfs_error = -ENOMEM; + page = bl_find_get_zeroing_page(wdata->inode, index, + cow_read); + if (unlikely(IS_ERR(page))) { + wdata->pnfs_error = PTR_ERR(page); goto out; - } - - /* PageDirty: Other will write this out - * PageWriteback: Other is writing this out - * PageUptodate: It was read before - * sector_initialized: already written out - */ - if (PageDirty(page) || PageWriteback(page)) { - print_page(page); - unlock_page(page); - page_cache_release(page); + } else if (page == NULL) goto next_page; - } - if (!PageUptodate(page)) { - /* New page, readin or zero it */ - init_page_for_write(page, cow_read); - } - set_page_writeback(page); - unlock_page(page); ret = bl_mark_sectors_init(be->be_inval, isect, PAGE_CACHE_SECTORS); |