3.16.81-rc1 review patch. If anyone has any objections, please let me know.
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From: Christoph Hellwig hch@lst.de
commit 343df3c79c62b644ce6ff5dff96c9e0be1ecb242 upstream.
Stop abusing struct page functionality and the swap end_io handler, and instead add a modified version of the blk-lib.c bio_batch helpers.
Also move the block I/O code into swap.c as they are directly tied into each other.
Signed-off-by: Christoph Hellwig hch@lst.de Tested-by: Pavel Machek pavel@ucw.cz Tested-by: Ming Lin mlin@kernel.org Acked-by: Pavel Machek pavel@ucw.cz Acked-by: Rafael J. Wysocki rjw@rjwysocki.net Signed-off-by: Jens Axboe axboe@fb.com [bwh: Backported to 3.16 as dependency of commit f6cf0545ec69 "PM / Hibernate: Call flush_icache_range() on pages restored in-place": - Adjust context] Signed-off-by: Ben Hutchings ben@decadent.org.uk --- include/linux/swap.h | 1 - kernel/power/Makefile | 3 +- kernel/power/block_io.c | 103 -------------------------- kernel/power/power.h | 9 --- kernel/power/swap.c | 159 ++++++++++++++++++++++++++++++---------- mm/page_io.c | 2 +- 6 files changed, 122 insertions(+), 155 deletions(-) delete mode 100644 kernel/power/block_io.c
--- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -395,7 +395,6 @@ extern void end_swap_bio_write(struct bi extern int __swap_writepage(struct page *page, struct writeback_control *wbc, void (*end_write_func)(struct bio *, int)); extern int swap_set_page_dirty(struct page *page); -extern void end_swap_bio_read(struct bio *bio, int err);
int add_swap_extent(struct swap_info_struct *sis, unsigned long start_page, unsigned long nr_pages, sector_t start_block); --- a/kernel/power/Makefile +++ b/kernel/power/Makefile @@ -7,8 +7,7 @@ obj-$(CONFIG_VT_CONSOLE_SLEEP) += consol obj-$(CONFIG_FREEZER) += process.o obj-$(CONFIG_SUSPEND) += suspend.o obj-$(CONFIG_PM_TEST_SUSPEND) += suspend_test.o -obj-$(CONFIG_HIBERNATION) += hibernate.o snapshot.o swap.o user.o \ - block_io.o +obj-$(CONFIG_HIBERNATION) += hibernate.o snapshot.o swap.o user.o obj-$(CONFIG_PM_AUTOSLEEP) += autosleep.o obj-$(CONFIG_PM_WAKELOCKS) += wakelock.o
--- a/kernel/power/block_io.c +++ /dev/null @@ -1,103 +0,0 @@ -/* - * This file provides functions for block I/O operations on swap/file. - * - * Copyright (C) 1998,2001-2005 Pavel Machek pavel@ucw.cz - * Copyright (C) 2006 Rafael J. Wysocki rjw@sisk.pl - * - * This file is released under the GPLv2. - */ - -#include <linux/bio.h> -#include <linux/kernel.h> -#include <linux/pagemap.h> -#include <linux/swap.h> - -#include "power.h" - -/** - * submit - submit BIO request. - * @rw: READ or WRITE. - * @off physical offset of page. - * @page: page we're reading or writing. - * @bio_chain: list of pending biod (for async reading) - * - * Straight from the textbook - allocate and initialize the bio. - * If we're reading, make sure the page is marked as dirty. - * Then submit it and, if @bio_chain == NULL, wait. - */ -static int submit(int rw, struct block_device *bdev, sector_t sector, - struct page *page, struct bio **bio_chain) -{ - const int bio_rw = rw | REQ_SYNC; - struct bio *bio; - - bio = bio_alloc(__GFP_WAIT | __GFP_HIGH, 1); - bio->bi_iter.bi_sector = sector; - bio->bi_bdev = bdev; - bio->bi_end_io = end_swap_bio_read; - - if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) { - printk(KERN_ERR "PM: Adding page to bio failed at %llu\n", - (unsigned long long)sector); - bio_put(bio); - return -EFAULT; - } - - lock_page(page); - bio_get(bio); - - if (bio_chain == NULL) { - submit_bio(bio_rw, bio); - wait_on_page_locked(page); - if (rw == READ) - bio_set_pages_dirty(bio); - bio_put(bio); - } else { - if (rw == READ) - get_page(page); /* These pages are freed later */ - bio->bi_private = *bio_chain; - *bio_chain = bio; - submit_bio(bio_rw, bio); - } - return 0; -} - -int hib_bio_read_page(pgoff_t page_off, void *addr, struct bio **bio_chain) -{ - return submit(READ, hib_resume_bdev, page_off * (PAGE_SIZE >> 9), - virt_to_page(addr), bio_chain); -} - -int hib_bio_write_page(pgoff_t page_off, void *addr, struct bio **bio_chain) -{ - return submit(WRITE, hib_resume_bdev, page_off * (PAGE_SIZE >> 9), - virt_to_page(addr), bio_chain); -} - -int hib_wait_on_bio_chain(struct bio **bio_chain) -{ - struct bio *bio; - struct bio *next_bio; - int ret = 0; - - if (bio_chain == NULL) - return 0; - - bio = *bio_chain; - if (bio == NULL) - return 0; - while (bio) { - struct page *page; - - next_bio = bio->bi_private; - page = bio->bi_io_vec[0].bv_page; - wait_on_page_locked(page); - if (!PageUptodate(page) || PageError(page)) - ret = -EIO; - put_page(page); - bio_put(bio); - bio = next_bio; - } - *bio_chain = NULL; - return ret; -} --- a/kernel/power/power.h +++ b/kernel/power/power.h @@ -163,15 +163,6 @@ extern void swsusp_close(fmode_t); extern int swsusp_unmark(void); #endif
-/* kernel/power/block_io.c */ -extern struct block_device *hib_resume_bdev; - -extern int hib_bio_read_page(pgoff_t page_off, void *addr, - struct bio **bio_chain); -extern int hib_bio_write_page(pgoff_t page_off, void *addr, - struct bio **bio_chain); -extern int hib_wait_on_bio_chain(struct bio **bio_chain); - struct timeval; /* kernel/power/swsusp.c */ extern void swsusp_show_speed(struct timeval *, struct timeval *, --- a/kernel/power/swap.c +++ b/kernel/power/swap.c @@ -211,7 +211,84 @@ int swsusp_swap_in_use(void) */
static unsigned short root_swap = 0xffff; -struct block_device *hib_resume_bdev; +static struct block_device *hib_resume_bdev; + +struct hib_bio_batch { + atomic_t count; + wait_queue_head_t wait; + int error; +}; + +static void hib_init_batch(struct hib_bio_batch *hb) +{ + atomic_set(&hb->count, 0); + init_waitqueue_head(&hb->wait); + hb->error = 0; +} + +static void hib_end_io(struct bio *bio, int error) +{ + struct hib_bio_batch *hb = bio->bi_private; + const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); + struct page *page = bio->bi_io_vec[0].bv_page; + + if (!uptodate || error) { + printk(KERN_ALERT "Read-error on swap-device (%u:%u:%Lu)\n", + imajor(bio->bi_bdev->bd_inode), + iminor(bio->bi_bdev->bd_inode), + (unsigned long long)bio->bi_iter.bi_sector); + + if (!error) + error = -EIO; + } + + if (bio_data_dir(bio) == WRITE) + put_page(page); + + if (error && !hb->error) + hb->error = error; + if (atomic_dec_and_test(&hb->count)) + wake_up(&hb->wait); + + bio_put(bio); +} + +static int hib_submit_io(int rw, pgoff_t page_off, void *addr, + struct hib_bio_batch *hb) +{ + struct page *page = virt_to_page(addr); + struct bio *bio; + int error = 0; + + bio = bio_alloc(__GFP_WAIT | __GFP_HIGH, 1); + bio->bi_iter.bi_sector = page_off * (PAGE_SIZE >> 9); + bio->bi_bdev = hib_resume_bdev; + + if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) { + printk(KERN_ERR "PM: Adding page to bio failed at %llu\n", + (unsigned long long)bio->bi_iter.bi_sector); + bio_put(bio); + return -EFAULT; + } + + if (hb) { + bio->bi_end_io = hib_end_io; + bio->bi_private = hb; + atomic_inc(&hb->count); + submit_bio(rw, bio); + } else { + error = submit_bio_wait(rw, bio); + bio_put(bio); + } + + return error; +} + +static int hib_wait_io(struct hib_bio_batch *hb) +{ + wait_event(hb->wait, atomic_read(&hb->count) == 0); + return hb->error; +}
/* * Saving part @@ -221,7 +298,7 @@ static int mark_swapfiles(struct swap_ma { int error;
- hib_bio_read_page(swsusp_resume_block, swsusp_header, NULL); + hib_submit_io(READ_SYNC, swsusp_resume_block, swsusp_header, NULL); if (!memcmp("SWAP-SPACE",swsusp_header->sig, 10) || !memcmp("SWAPSPACE2",swsusp_header->sig, 10)) { memcpy(swsusp_header->orig_sig,swsusp_header->sig, 10); @@ -230,7 +307,7 @@ static int mark_swapfiles(struct swap_ma swsusp_header->flags = flags; if (flags & SF_CRC32_MODE) swsusp_header->crc32 = handle->crc32; - error = hib_bio_write_page(swsusp_resume_block, + error = hib_submit_io(WRITE_SYNC, swsusp_resume_block, swsusp_header, NULL); } else { printk(KERN_ERR "PM: Swap header not found!\n"); @@ -270,10 +347,10 @@ static int swsusp_swap_check(void) * write_page - Write one page to given swap location. * @buf: Address we're writing. * @offset: Offset of the swap page we're writing to. - * @bio_chain: Link the next write BIO here + * @hb: bio completion batch */
-static int write_page(void *buf, sector_t offset, struct bio **bio_chain) +static int write_page(void *buf, sector_t offset, struct hib_bio_batch *hb) { void *src; int ret; @@ -281,13 +358,13 @@ static int write_page(void *buf, sector_ if (!offset) return -ENOSPC;
- if (bio_chain) { + if (hb) { src = (void *)__get_free_page(__GFP_WAIT | __GFP_NOWARN | __GFP_NORETRY); if (src) { copy_page(src, buf); } else { - ret = hib_wait_on_bio_chain(bio_chain); /* Free pages */ + ret = hib_wait_io(hb); /* Free pages */ if (ret) return ret; src = (void *)__get_free_page(__GFP_WAIT | @@ -297,14 +374,14 @@ static int write_page(void *buf, sector_ copy_page(src, buf); } else { WARN_ON_ONCE(1); - bio_chain = NULL; /* Go synchronous */ + hb = NULL; /* Go synchronous */ src = buf; } } } else { src = buf; } - return hib_bio_write_page(offset, src, bio_chain); + return hib_submit_io(WRITE_SYNC, offset, src, hb); }
static void release_swap_writer(struct swap_map_handle *handle) @@ -347,7 +424,7 @@ err_close: }
static int swap_write_page(struct swap_map_handle *handle, void *buf, - struct bio **bio_chain) + struct hib_bio_batch *hb) { int error = 0; sector_t offset; @@ -355,7 +432,7 @@ static int swap_write_page(struct swap_m if (!handle->cur) return -EINVAL; offset = alloc_swapdev_block(root_swap); - error = write_page(buf, offset, bio_chain); + error = write_page(buf, offset, hb); if (error) return error; handle->cur->entries[handle->k++] = offset; @@ -364,15 +441,15 @@ static int swap_write_page(struct swap_m if (!offset) return -ENOSPC; handle->cur->next_swap = offset; - error = write_page(handle->cur, handle->cur_swap, bio_chain); + error = write_page(handle->cur, handle->cur_swap, hb); if (error) goto out; clear_page(handle->cur); handle->cur_swap = offset; handle->k = 0;
- if (bio_chain && low_free_pages() <= handle->reqd_free_pages) { - error = hib_wait_on_bio_chain(bio_chain); + if (hb && low_free_pages() <= handle->reqd_free_pages) { + error = hib_wait_io(hb); if (error) goto out; /* @@ -444,23 +521,24 @@ static int save_image(struct swap_map_ha int ret; int nr_pages; int err2; - struct bio *bio; + struct hib_bio_batch hb; struct timeval start; struct timeval stop;
+ hib_init_batch(&hb); + printk(KERN_INFO "PM: Saving image data pages (%u pages)...\n", nr_to_write); m = nr_to_write / 10; if (!m) m = 1; nr_pages = 0; - bio = NULL; do_gettimeofday(&start); while (1) { ret = snapshot_read_next(snapshot); if (ret <= 0) break; - ret = swap_write_page(handle, data_of(*snapshot), &bio); + ret = swap_write_page(handle, data_of(*snapshot), &hb); if (ret) break; if (!(nr_pages % m)) @@ -468,7 +546,7 @@ static int save_image(struct swap_map_ha nr_pages / m * 10); nr_pages++; } - err2 = hib_wait_on_bio_chain(&bio); + err2 = hib_wait_io(&hb); do_gettimeofday(&stop); if (!ret) ret = err2; @@ -579,7 +657,7 @@ static int save_image_lzo(struct swap_ma int ret = 0; int nr_pages; int err2; - struct bio *bio; + struct hib_bio_batch hb; struct timeval start; struct timeval stop; size_t off; @@ -588,6 +666,8 @@ static int save_image_lzo(struct swap_ma struct cmp_data *data = NULL; struct crc_data *crc = NULL;
+ hib_init_batch(&hb); + /* * We'll limit the number of threads for compression to limit memory * footprint. @@ -673,7 +753,6 @@ static int save_image_lzo(struct swap_ma if (!m) m = 1; nr_pages = 0; - bio = NULL; do_gettimeofday(&start); for (;;) { for (thr = 0; thr < nr_threads; thr++) { @@ -747,7 +826,7 @@ static int save_image_lzo(struct swap_ma off += PAGE_SIZE) { memcpy(page, data[thr].cmp + off, PAGE_SIZE);
- ret = swap_write_page(handle, page, &bio); + ret = swap_write_page(handle, page, &hb); if (ret) goto out_finish; } @@ -758,7 +837,7 @@ static int save_image_lzo(struct swap_ma }
out_finish: - err2 = hib_wait_on_bio_chain(&bio); + err2 = hib_wait_io(&hb); do_gettimeofday(&stop); if (!ret) ret = err2; @@ -905,7 +984,7 @@ static int get_swap_reader(struct swap_m return -ENOMEM; }
- error = hib_bio_read_page(offset, tmp->map, NULL); + error = hib_submit_io(READ_SYNC, offset, tmp->map, NULL); if (error) { release_swap_reader(handle); return error; @@ -918,7 +997,7 @@ static int get_swap_reader(struct swap_m }
static int swap_read_page(struct swap_map_handle *handle, void *buf, - struct bio **bio_chain) + struct hib_bio_batch *hb) { sector_t offset; int error; @@ -929,7 +1008,7 @@ static int swap_read_page(struct swap_ma offset = handle->cur->entries[handle->k]; if (!offset) return -EFAULT; - error = hib_bio_read_page(offset, buf, bio_chain); + error = hib_submit_io(READ_SYNC, offset, buf, hb); if (error) return error; if (++handle->k >= MAP_PAGE_ENTRIES) { @@ -967,27 +1046,28 @@ static int load_image(struct swap_map_ha int ret = 0; struct timeval start; struct timeval stop; - struct bio *bio; + struct hib_bio_batch hb; int err2; unsigned nr_pages;
+ hib_init_batch(&hb); + printk(KERN_INFO "PM: Loading image data pages (%u pages)...\n", nr_to_read); m = nr_to_read / 10; if (!m) m = 1; nr_pages = 0; - bio = NULL; do_gettimeofday(&start); for ( ; ; ) { ret = snapshot_write_next(snapshot); if (ret <= 0) break; - ret = swap_read_page(handle, data_of(*snapshot), &bio); + ret = swap_read_page(handle, data_of(*snapshot), &hb); if (ret) break; if (snapshot->sync_read) - ret = hib_wait_on_bio_chain(&bio); + ret = hib_wait_io(&hb); if (ret) break; if (!(nr_pages % m)) @@ -995,7 +1075,7 @@ static int load_image(struct swap_map_ha nr_pages / m * 10); nr_pages++; } - err2 = hib_wait_on_bio_chain(&bio); + err2 = hib_wait_io(&hb); do_gettimeofday(&stop); if (!ret) ret = err2; @@ -1066,7 +1146,7 @@ static int load_image_lzo(struct swap_ma unsigned int m; int ret = 0; int eof = 0; - struct bio *bio; + struct hib_bio_batch hb; struct timeval start; struct timeval stop; unsigned nr_pages; @@ -1079,6 +1159,8 @@ static int load_image_lzo(struct swap_ma struct dec_data *data = NULL; struct crc_data *crc = NULL;
+ hib_init_batch(&hb); + /* * We'll limit the number of threads for decompression to limit memory * footprint. @@ -1189,7 +1271,6 @@ static int load_image_lzo(struct swap_ma if (!m) m = 1; nr_pages = 0; - bio = NULL; do_gettimeofday(&start);
ret = snapshot_write_next(snapshot); @@ -1198,7 +1279,7 @@ static int load_image_lzo(struct swap_ma
for(;;) { for (i = 0; !eof && i < want; i++) { - ret = swap_read_page(handle, page[ring], &bio); + ret = swap_read_page(handle, page[ring], &hb); if (ret) { /* * On real read error, finish. On end of data, @@ -1225,7 +1306,7 @@ static int load_image_lzo(struct swap_ma if (!asked) break;
- ret = hib_wait_on_bio_chain(&bio); + ret = hib_wait_io(&hb); if (ret) goto out_finish; have += asked; @@ -1280,7 +1361,7 @@ static int load_image_lzo(struct swap_ma * Wait for more data while we are decompressing. */ if (have < LZO_CMP_PAGES && asked) { - ret = hib_wait_on_bio_chain(&bio); + ret = hib_wait_io(&hb); if (ret) goto out_finish; have += asked; @@ -1429,7 +1510,7 @@ int swsusp_check(void) if (!IS_ERR(hib_resume_bdev)) { set_blocksize(hib_resume_bdev, PAGE_SIZE); clear_page(swsusp_header); - error = hib_bio_read_page(swsusp_resume_block, + error = hib_submit_io(READ_SYNC, swsusp_resume_block, swsusp_header, NULL); if (error) goto put; @@ -1437,7 +1518,7 @@ int swsusp_check(void) if (!memcmp(HIBERNATE_SIG, swsusp_header->sig, 10)) { memcpy(swsusp_header->sig, swsusp_header->orig_sig, 10); /* Reset swap signature now */ - error = hib_bio_write_page(swsusp_resume_block, + error = hib_submit_io(WRITE_SYNC, swsusp_resume_block, swsusp_header, NULL); } else { error = -EINVAL; @@ -1481,10 +1562,10 @@ int swsusp_unmark(void) { int error;
- hib_bio_read_page(swsusp_resume_block, swsusp_header, NULL); + hib_submit_io(READ_SYNC, swsusp_resume_block, swsusp_header, NULL); if (!memcmp(HIBERNATE_SIG,swsusp_header->sig, 10)) { memcpy(swsusp_header->sig,swsusp_header->orig_sig, 10); - error = hib_bio_write_page(swsusp_resume_block, + error = hib_submit_io(WRITE_SYNC, swsusp_resume_block, swsusp_header, NULL); } else { printk(KERN_ERR "PM: Cannot find swsusp signature!\n"); --- a/mm/page_io.c +++ b/mm/page_io.c @@ -69,7 +69,7 @@ void end_swap_bio_write(struct bio *bio, bio_put(bio); }
-void end_swap_bio_read(struct bio *bio, int err) +static void end_swap_bio_read(struct bio *bio, int err) { const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); struct page *page = bio->bi_io_vec[0].bv_page;