diff --git a/fs/nfs/file.c b/fs/nfs/file.c index 6b4a79f4ad1d30a0ddf036df224ab80594274f38..94e94bd11aae6d0a6c32acf5c16491448edb93f8 100644 --- a/fs/nfs/file.c +++ b/fs/nfs/file.c @@ -495,6 +495,35 @@ static int nfs_release_page(struct page *page, gfp_t gfp) return nfs_fscache_release_page(page, gfp); } +static void nfs_check_dirty_writeback(struct page *page, + bool *dirty, bool *writeback) +{ + struct nfs_inode *nfsi; + struct address_space *mapping = page_file_mapping(page); + + if (!mapping || PageSwapCache(page)) + return; + + /* + * Check if an unstable page is currently being committed and + * if so, have the VM treat it as if the page is under writeback + * so it will not block due to pages that will shortly be freeable. + */ + nfsi = NFS_I(mapping->host); + if (test_bit(NFS_INO_COMMIT, &nfsi->flags)) { + *writeback = true; + return; + } + + /* + * If PagePrivate() is set, then the page is not freeable and as the + * inode is not being committed, it's not going to be cleaned in the + * near future so treat it as dirty + */ + if (PagePrivate(page)) + *dirty = true; +} + /* * Attempt to clear the private state associated with a page when an error * occurs that requires the cached contents of an inode to be written back or @@ -542,6 +571,7 @@ const struct address_space_operations nfs_file_aops = { .direct_IO = nfs_direct_IO, .migratepage = nfs_migrate_page, .launder_page = nfs_launder_page, + .is_dirty_writeback = nfs_check_dirty_writeback, .error_remove_page = generic_error_remove_page, #ifdef CONFIG_NFS_SWAP .swap_activate = nfs_swap_activate,