|  | /* | 
|  | * Copyright (C) 2013 Fusion IO.  All rights reserved. | 
|  | * | 
|  | * This program is free software; you can redistribute it and/or | 
|  | * modify it under the terms of the GNU General Public | 
|  | * License v2 as published by the Free Software Foundation. | 
|  | * | 
|  | * This program is distributed in the hope that it will be useful, | 
|  | * but WITHOUT ANY WARRANTY; without even the implied warranty of | 
|  | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU | 
|  | * General Public License for more details. | 
|  | * | 
|  | * You should have received a copy of the GNU General Public | 
|  | * License along with this program; if not, write to the | 
|  | * Free Software Foundation, Inc., 59 Temple Place - Suite 330, | 
|  | * Boston, MA 021110-1307, USA. | 
|  | */ | 
|  |  | 
|  | #include <linux/pagemap.h> | 
|  | #include <linux/sched.h> | 
|  | #include "btrfs-tests.h" | 
|  | #include "../extent_io.h" | 
|  |  | 
|  | #define PROCESS_UNLOCK		(1 << 0) | 
|  | #define PROCESS_RELEASE		(1 << 1) | 
|  | #define PROCESS_TEST_LOCKED	(1 << 2) | 
|  |  | 
|  | static noinline int process_page_range(struct inode *inode, u64 start, u64 end, | 
|  | unsigned long flags) | 
|  | { | 
|  | int ret; | 
|  | struct page *pages[16]; | 
|  | unsigned long index = start >> PAGE_CACHE_SHIFT; | 
|  | unsigned long end_index = end >> PAGE_CACHE_SHIFT; | 
|  | unsigned long nr_pages = end_index - index + 1; | 
|  | int i; | 
|  | int count = 0; | 
|  | int loops = 0; | 
|  |  | 
|  | while (nr_pages > 0) { | 
|  | ret = find_get_pages_contig(inode->i_mapping, index, | 
|  | min_t(unsigned long, nr_pages, | 
|  | ARRAY_SIZE(pages)), pages); | 
|  | for (i = 0; i < ret; i++) { | 
|  | if (flags & PROCESS_TEST_LOCKED && | 
|  | !PageLocked(pages[i])) | 
|  | count++; | 
|  | if (flags & PROCESS_UNLOCK && PageLocked(pages[i])) | 
|  | unlock_page(pages[i]); | 
|  | page_cache_release(pages[i]); | 
|  | if (flags & PROCESS_RELEASE) | 
|  | page_cache_release(pages[i]); | 
|  | } | 
|  | nr_pages -= ret; | 
|  | index += ret; | 
|  | cond_resched(); | 
|  | loops++; | 
|  | if (loops > 100000) { | 
|  | printk(KERN_ERR "stuck in a loop, start %Lu, end %Lu, nr_pages %lu, ret %d\n", start, end, nr_pages, ret); | 
|  | break; | 
|  | } | 
|  | } | 
|  | return count; | 
|  | } | 
|  |  | 
|  | static int test_find_delalloc(void) | 
|  | { | 
|  | struct inode *inode; | 
|  | struct extent_io_tree tmp; | 
|  | struct page *page; | 
|  | struct page *locked_page = NULL; | 
|  | unsigned long index = 0; | 
|  | u64 total_dirty = 256 * 1024 * 1024; | 
|  | u64 max_bytes = 128 * 1024 * 1024; | 
|  | u64 start, end, test_start; | 
|  | u64 found; | 
|  | int ret = -EINVAL; | 
|  |  | 
|  | inode = btrfs_new_test_inode(); | 
|  | if (!inode) { | 
|  | test_msg("Failed to allocate test inode\n"); | 
|  | return -ENOMEM; | 
|  | } | 
|  |  | 
|  | extent_io_tree_init(&tmp, &inode->i_data); | 
|  |  | 
|  | /* | 
|  | * First go through and create and mark all of our pages dirty, we pin | 
|  | * everything to make sure our pages don't get evicted and screw up our | 
|  | * test. | 
|  | */ | 
|  | for (index = 0; index < (total_dirty >> PAGE_CACHE_SHIFT); index++) { | 
|  | page = find_or_create_page(inode->i_mapping, index, GFP_NOFS); | 
|  | if (!page) { | 
|  | test_msg("Failed to allocate test page\n"); | 
|  | ret = -ENOMEM; | 
|  | goto out; | 
|  | } | 
|  | SetPageDirty(page); | 
|  | if (index) { | 
|  | unlock_page(page); | 
|  | } else { | 
|  | page_cache_get(page); | 
|  | locked_page = page; | 
|  | } | 
|  | } | 
|  |  | 
|  | /* Test this scenario | 
|  | * |--- delalloc ---| | 
|  | * |---  search  ---| | 
|  | */ | 
|  | set_extent_delalloc(&tmp, 0, 4095, NULL, GFP_NOFS); | 
|  | start = 0; | 
|  | end = 0; | 
|  | found = find_lock_delalloc_range(inode, &tmp, locked_page, &start, | 
|  | &end, max_bytes); | 
|  | if (!found) { | 
|  | test_msg("Should have found at least one delalloc\n"); | 
|  | goto out_bits; | 
|  | } | 
|  | if (start != 0 || end != 4095) { | 
|  | test_msg("Expected start 0 end 4095, got start %Lu end %Lu\n", | 
|  | start, end); | 
|  | goto out_bits; | 
|  | } | 
|  | unlock_extent(&tmp, start, end); | 
|  | unlock_page(locked_page); | 
|  | page_cache_release(locked_page); | 
|  |  | 
|  | /* | 
|  | * Test this scenario | 
|  | * | 
|  | * |--- delalloc ---| | 
|  | *           |--- search ---| | 
|  | */ | 
|  | test_start = 64 * 1024 * 1024; | 
|  | locked_page = find_lock_page(inode->i_mapping, | 
|  | test_start >> PAGE_CACHE_SHIFT); | 
|  | if (!locked_page) { | 
|  | test_msg("Couldn't find the locked page\n"); | 
|  | goto out_bits; | 
|  | } | 
|  | set_extent_delalloc(&tmp, 4096, max_bytes - 1, NULL, GFP_NOFS); | 
|  | start = test_start; | 
|  | end = 0; | 
|  | found = find_lock_delalloc_range(inode, &tmp, locked_page, &start, | 
|  | &end, max_bytes); | 
|  | if (!found) { | 
|  | test_msg("Couldn't find delalloc in our range\n"); | 
|  | goto out_bits; | 
|  | } | 
|  | if (start != test_start || end != max_bytes - 1) { | 
|  | test_msg("Expected start %Lu end %Lu, got start %Lu, end " | 
|  | "%Lu\n", test_start, max_bytes - 1, start, end); | 
|  | goto out_bits; | 
|  | } | 
|  | if (process_page_range(inode, start, end, | 
|  | PROCESS_TEST_LOCKED | PROCESS_UNLOCK)) { | 
|  | test_msg("There were unlocked pages in the range\n"); | 
|  | goto out_bits; | 
|  | } | 
|  | unlock_extent(&tmp, start, end); | 
|  | /* locked_page was unlocked above */ | 
|  | page_cache_release(locked_page); | 
|  |  | 
|  | /* | 
|  | * Test this scenario | 
|  | * |--- delalloc ---| | 
|  | *                    |--- search ---| | 
|  | */ | 
|  | test_start = max_bytes + 4096; | 
|  | locked_page = find_lock_page(inode->i_mapping, test_start >> | 
|  | PAGE_CACHE_SHIFT); | 
|  | if (!locked_page) { | 
|  | test_msg("Could'nt find the locked page\n"); | 
|  | goto out_bits; | 
|  | } | 
|  | start = test_start; | 
|  | end = 0; | 
|  | found = find_lock_delalloc_range(inode, &tmp, locked_page, &start, | 
|  | &end, max_bytes); | 
|  | if (found) { | 
|  | test_msg("Found range when we shouldn't have\n"); | 
|  | goto out_bits; | 
|  | } | 
|  | if (end != (u64)-1) { | 
|  | test_msg("Did not return the proper end offset\n"); | 
|  | goto out_bits; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Test this scenario | 
|  | * [------- delalloc -------| | 
|  | * [max_bytes]|-- search--| | 
|  | * | 
|  | * We are re-using our test_start from above since it works out well. | 
|  | */ | 
|  | set_extent_delalloc(&tmp, max_bytes, total_dirty - 1, NULL, GFP_NOFS); | 
|  | start = test_start; | 
|  | end = 0; | 
|  | found = find_lock_delalloc_range(inode, &tmp, locked_page, &start, | 
|  | &end, max_bytes); | 
|  | if (!found) { | 
|  | test_msg("Didn't find our range\n"); | 
|  | goto out_bits; | 
|  | } | 
|  | if (start != test_start || end != total_dirty - 1) { | 
|  | test_msg("Expected start %Lu end %Lu, got start %Lu end %Lu\n", | 
|  | test_start, total_dirty - 1, start, end); | 
|  | goto out_bits; | 
|  | } | 
|  | if (process_page_range(inode, start, end, | 
|  | PROCESS_TEST_LOCKED | PROCESS_UNLOCK)) { | 
|  | test_msg("Pages in range were not all locked\n"); | 
|  | goto out_bits; | 
|  | } | 
|  | unlock_extent(&tmp, start, end); | 
|  |  | 
|  | /* | 
|  | * Now to test where we run into a page that is no longer dirty in the | 
|  | * range we want to find. | 
|  | */ | 
|  | page = find_get_page(inode->i_mapping, (max_bytes + (1 * 1024 * 1024)) | 
|  | >> PAGE_CACHE_SHIFT); | 
|  | if (!page) { | 
|  | test_msg("Couldn't find our page\n"); | 
|  | goto out_bits; | 
|  | } | 
|  | ClearPageDirty(page); | 
|  | page_cache_release(page); | 
|  |  | 
|  | /* We unlocked it in the previous test */ | 
|  | lock_page(locked_page); | 
|  | start = test_start; | 
|  | end = 0; | 
|  | /* | 
|  | * Currently if we fail to find dirty pages in the delalloc range we | 
|  | * will adjust max_bytes down to PAGE_CACHE_SIZE and then re-search.  If | 
|  | * this changes at any point in the future we will need to fix this | 
|  | * tests expected behavior. | 
|  | */ | 
|  | found = find_lock_delalloc_range(inode, &tmp, locked_page, &start, | 
|  | &end, max_bytes); | 
|  | if (!found) { | 
|  | test_msg("Didn't find our range\n"); | 
|  | goto out_bits; | 
|  | } | 
|  | if (start != test_start && end != test_start + PAGE_CACHE_SIZE - 1) { | 
|  | test_msg("Expected start %Lu end %Lu, got start %Lu end %Lu\n", | 
|  | test_start, test_start + PAGE_CACHE_SIZE - 1, start, | 
|  | end); | 
|  | goto out_bits; | 
|  | } | 
|  | if (process_page_range(inode, start, end, PROCESS_TEST_LOCKED | | 
|  | PROCESS_UNLOCK)) { | 
|  | test_msg("Pages in range were not all locked\n"); | 
|  | goto out_bits; | 
|  | } | 
|  | ret = 0; | 
|  | out_bits: | 
|  | clear_extent_bits(&tmp, 0, total_dirty - 1, (unsigned)-1, GFP_NOFS); | 
|  | out: | 
|  | if (locked_page) | 
|  | page_cache_release(locked_page); | 
|  | process_page_range(inode, 0, total_dirty - 1, | 
|  | PROCESS_UNLOCK | PROCESS_RELEASE); | 
|  | iput(inode); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | int btrfs_test_extent_io(void) | 
|  | { | 
|  | test_msg("Running find delalloc tests\n"); | 
|  | return test_find_delalloc(); | 
|  | } |