1b2441318SGreg Kroah-Hartman // SPDX-License-Identifier: GPL-2.0 2bd2d0210STheodore Ts'o /* 3bd2d0210STheodore Ts'o * linux/fs/ext4/page-io.c 4bd2d0210STheodore Ts'o * 5bd2d0210STheodore Ts'o * This contains the new page_io functions for ext4 6bd2d0210STheodore Ts'o * 7bd2d0210STheodore Ts'o * Written by Theodore Ts'o, 2010. 8bd2d0210STheodore Ts'o */ 9bd2d0210STheodore Ts'o 10bd2d0210STheodore Ts'o #include <linux/fs.h> 11bd2d0210STheodore Ts'o #include <linux/time.h> 12bd2d0210STheodore Ts'o #include <linux/highuid.h> 13bd2d0210STheodore Ts'o #include <linux/pagemap.h> 14bd2d0210STheodore Ts'o #include <linux/quotaops.h> 15bd2d0210STheodore Ts'o #include <linux/string.h> 16bd2d0210STheodore Ts'o #include <linux/buffer_head.h> 17bd2d0210STheodore Ts'o #include <linux/writeback.h> 18bd2d0210STheodore Ts'o #include <linux/pagevec.h> 19bd2d0210STheodore Ts'o #include <linux/mpage.h> 20bd2d0210STheodore Ts'o #include <linux/namei.h> 21bd2d0210STheodore Ts'o #include <linux/uio.h> 22bd2d0210STheodore Ts'o #include <linux/bio.h> 23bd2d0210STheodore Ts'o #include <linux/workqueue.h> 24bd2d0210STheodore Ts'o #include <linux/kernel.h> 25bd2d0210STheodore Ts'o #include <linux/slab.h> 261ae48a63SJan Kara #include <linux/mm.h> 274034247aSNeilBrown #include <linux/sched/mm.h> 28bd2d0210STheodore Ts'o 29bd2d0210STheodore Ts'o #include "ext4_jbd2.h" 30bd2d0210STheodore Ts'o #include "xattr.h" 31bd2d0210STheodore Ts'o #include "acl.h" 32bd2d0210STheodore Ts'o 330058f965SJan Kara static struct kmem_cache *io_end_cachep; 34c8cc8816SRitesh Harjani static struct kmem_cache *io_end_vec_cachep; 35bd2d0210STheodore Ts'o 365dabfc78STheodore Ts'o int __init ext4_init_pageio(void) 37bd2d0210STheodore Ts'o { 38bd2d0210STheodore Ts'o io_end_cachep = KMEM_CACHE(ext4_io_end, SLAB_RECLAIM_ACCOUNT); 390058f965SJan Kara if (io_end_cachep == NULL) 40bd2d0210STheodore Ts'o return -ENOMEM; 41c8cc8816SRitesh Harjani 42c8cc8816SRitesh Harjani io_end_vec_cachep = KMEM_CACHE(ext4_io_end_vec, 0); 43c8cc8816SRitesh Harjani if (io_end_vec_cachep == NULL) { 44c8cc8816SRitesh Harjani kmem_cache_destroy(io_end_cachep); 45c8cc8816SRitesh Harjani return -ENOMEM; 46c8cc8816SRitesh Harjani } 47bd2d0210STheodore Ts'o return 0; 48bd2d0210STheodore Ts'o } 49bd2d0210STheodore Ts'o 505dabfc78STheodore Ts'o void ext4_exit_pageio(void) 51bd2d0210STheodore Ts'o { 52bd2d0210STheodore Ts'o kmem_cache_destroy(io_end_cachep); 53c8cc8816SRitesh Harjani kmem_cache_destroy(io_end_vec_cachep); 54c8cc8816SRitesh Harjani } 55c8cc8816SRitesh Harjani 56c8cc8816SRitesh Harjani struct ext4_io_end_vec *ext4_alloc_io_end_vec(ext4_io_end_t *io_end) 57c8cc8816SRitesh Harjani { 58c8cc8816SRitesh Harjani struct ext4_io_end_vec *io_end_vec; 59c8cc8816SRitesh Harjani 60c8cc8816SRitesh Harjani io_end_vec = kmem_cache_zalloc(io_end_vec_cachep, GFP_NOFS); 61c8cc8816SRitesh Harjani if (!io_end_vec) 62c8cc8816SRitesh Harjani return ERR_PTR(-ENOMEM); 63c8cc8816SRitesh Harjani INIT_LIST_HEAD(&io_end_vec->list); 64c8cc8816SRitesh Harjani list_add_tail(&io_end_vec->list, &io_end->list_vec); 65c8cc8816SRitesh Harjani return io_end_vec; 66c8cc8816SRitesh Harjani } 67c8cc8816SRitesh Harjani 68c8cc8816SRitesh Harjani static void ext4_free_io_end_vec(ext4_io_end_t *io_end) 69c8cc8816SRitesh Harjani { 70c8cc8816SRitesh Harjani struct ext4_io_end_vec *io_end_vec, *tmp; 71c8cc8816SRitesh Harjani 72c8cc8816SRitesh Harjani if (list_empty(&io_end->list_vec)) 73c8cc8816SRitesh Harjani return; 74c8cc8816SRitesh Harjani list_for_each_entry_safe(io_end_vec, tmp, &io_end->list_vec, list) { 75c8cc8816SRitesh Harjani list_del(&io_end_vec->list); 76c8cc8816SRitesh Harjani kmem_cache_free(io_end_vec_cachep, io_end_vec); 77c8cc8816SRitesh Harjani } 78c8cc8816SRitesh Harjani } 79c8cc8816SRitesh Harjani 80c8cc8816SRitesh Harjani struct ext4_io_end_vec *ext4_last_io_end_vec(ext4_io_end_t *io_end) 81c8cc8816SRitesh Harjani { 82c8cc8816SRitesh Harjani BUG_ON(list_empty(&io_end->list_vec)); 83c8cc8816SRitesh Harjani return list_last_entry(&io_end->list_vec, struct ext4_io_end_vec, list); 84bd2d0210STheodore Ts'o } 85bd2d0210STheodore Ts'o 861ada47d9STheodore Ts'o /* 87b0857d30SJan Kara * Print an buffer I/O error compatible with the fs/buffer.c. This 88b0857d30SJan Kara * provides compatibility with dmesg scrapers that look for a specific 89b0857d30SJan Kara * buffer I/O error message. We really need a unified error reporting 90b0857d30SJan Kara * structure to userspace ala Digital Unix's uerf system, but it's 91b0857d30SJan Kara * probably not going to happen in my lifetime, due to LKML politics... 92b0857d30SJan Kara */ 93b0857d30SJan Kara static void buffer_io_error(struct buffer_head *bh) 94b0857d30SJan Kara { 95a1c6f057SDmitry Monakhov printk_ratelimited(KERN_ERR "Buffer I/O error on device %pg, logical block %llu\n", 96a1c6f057SDmitry Monakhov bh->b_bdev, 97b0857d30SJan Kara (unsigned long long)bh->b_blocknr); 98b0857d30SJan Kara } 99b0857d30SJan Kara 100b0857d30SJan Kara static void ext4_finish_bio(struct bio *bio) 101b0857d30SJan Kara { 1022c30c71bSKent Overstreet struct bio_vec *bvec; 1036dc4f100SMing Lei struct bvec_iter_all iter_all; 104b0857d30SJan Kara 1052b070cfeSChristoph Hellwig bio_for_each_segment_all(bvec, bio, iter_all) { 106b0857d30SJan Kara struct page *page = bvec->bv_page; 107d2d0727bSEric Biggers struct page *bounce_page = NULL; 108b0857d30SJan Kara struct buffer_head *bh, *head; 109b0857d30SJan Kara unsigned bio_start = bvec->bv_offset; 110b0857d30SJan Kara unsigned bio_end = bio_start + bvec->bv_len; 111b0857d30SJan Kara unsigned under_io = 0; 112b0857d30SJan Kara unsigned long flags; 113b0857d30SJan Kara 114d2d0727bSEric Biggers if (fscrypt_is_bounce_page(page)) { 115d2d0727bSEric Biggers bounce_page = page; 116d2d0727bSEric Biggers page = fscrypt_pagecache_page(bounce_page); 1172058f83aSMichael Halcrow } 1182058f83aSMichael Halcrow 1194e4cbee9SChristoph Hellwig if (bio->bi_status) { 120b0857d30SJan Kara SetPageError(page); 1215114a97aSMichal Hocko mapping_set_error(page->mapping, -EIO); 122b0857d30SJan Kara } 123b0857d30SJan Kara bh = head = page_buffers(page); 124b0857d30SJan Kara /* 125f1e67e35SThomas Gleixner * We check all buffers in the page under b_uptodate_lock 126b0857d30SJan Kara * to avoid races with other end io clearing async_write flags 127b0857d30SJan Kara */ 128f1e67e35SThomas Gleixner spin_lock_irqsave(&head->b_uptodate_lock, flags); 129b0857d30SJan Kara do { 130b0857d30SJan Kara if (bh_offset(bh) < bio_start || 131b0857d30SJan Kara bh_offset(bh) + bh->b_size > bio_end) { 132b0857d30SJan Kara if (buffer_async_write(bh)) 133b0857d30SJan Kara under_io++; 134b0857d30SJan Kara continue; 135b0857d30SJan Kara } 136b0857d30SJan Kara clear_buffer_async_write(bh); 1374e4cbee9SChristoph Hellwig if (bio->bi_status) 138b0857d30SJan Kara buffer_io_error(bh); 139b0857d30SJan Kara } while ((bh = bh->b_this_page) != head); 140f1e67e35SThomas Gleixner spin_unlock_irqrestore(&head->b_uptodate_lock, flags); 1412058f83aSMichael Halcrow if (!under_io) { 142d2d0727bSEric Biggers fscrypt_free_bounce_page(bounce_page); 143b0857d30SJan Kara end_page_writeback(page); 144b0857d30SJan Kara } 145b0857d30SJan Kara } 1462058f83aSMichael Halcrow } 147b0857d30SJan Kara 14897a851edSJan Kara static void ext4_release_io_end(ext4_io_end_t *io_end) 149bd2d0210STheodore Ts'o { 150b0857d30SJan Kara struct bio *bio, *next_bio; 151b0857d30SJan Kara 15297a851edSJan Kara BUG_ON(!list_empty(&io_end->list)); 15397a851edSJan Kara BUG_ON(io_end->flag & EXT4_IO_END_UNWRITTEN); 1546b523df4SJan Kara WARN_ON(io_end->handle); 155bd2d0210STheodore Ts'o 156b0857d30SJan Kara for (bio = io_end->bio; bio; bio = next_bio) { 157b0857d30SJan Kara next_bio = bio->bi_private; 158b0857d30SJan Kara ext4_finish_bio(bio); 159b0857d30SJan Kara bio_put(bio); 160b0857d30SJan Kara } 161c8cc8816SRitesh Harjani ext4_free_io_end_vec(io_end); 16297a851edSJan Kara kmem_cache_free(io_end_cachep, io_end); 16397a851edSJan Kara } 16497a851edSJan Kara 165a115f749SJan Kara /* 166a115f749SJan Kara * Check a range of space and convert unwritten extents to written. Note that 167a115f749SJan Kara * we are protected from truncate touching same part of extent tree by the 168a115f749SJan Kara * fact that truncate code waits for all DIO to finish (thus exclusion from 169a115f749SJan Kara * direct IO is achieved) and also waits for PageWriteback bits. Thus we 170a115f749SJan Kara * cannot get to ext4_ext_truncate() before all IOs overlapping that range are 171a115f749SJan Kara * completed (happens from ext4_free_ioend()). 172a115f749SJan Kara */ 173821ff38dSRitesh Harjani static int ext4_end_io_end(ext4_io_end_t *io_end) 174bd2d0210STheodore Ts'o { 175821ff38dSRitesh Harjani struct inode *inode = io_end->inode; 176821ff38dSRitesh Harjani handle_t *handle = io_end->handle; 177bd2d0210STheodore Ts'o int ret = 0; 178bd2d0210STheodore Ts'o 179821ff38dSRitesh Harjani ext4_debug("ext4_end_io_nolock: io_end 0x%p from inode %lu,list->next 0x%p," 180bd2d0210STheodore Ts'o "list->prev 0x%p\n", 181821ff38dSRitesh Harjani io_end, inode->i_ino, io_end->list.next, io_end->list.prev); 182bd2d0210STheodore Ts'o 183821ff38dSRitesh Harjani io_end->handle = NULL; /* Following call will use up the handle */ 184a00713eaSRitesh Harjani ret = ext4_convert_unwritten_io_end_vec(handle, io_end); 1850db1ff22STheodore Ts'o if (ret < 0 && !ext4_forced_shutdown(EXT4_SB(inode->i_sb))) { 186b82e384cSTheodore Ts'o ext4_msg(inode->i_sb, KERN_EMERG, 187b82e384cSTheodore Ts'o "failed to convert unwritten extents to written " 188b82e384cSTheodore Ts'o "extents -- potential data loss! " 189c8cc8816SRitesh Harjani "(inode %lu, error %d)", inode->i_ino, ret); 190bd2d0210STheodore Ts'o } 191821ff38dSRitesh Harjani ext4_clear_io_unwritten_flag(io_end); 192821ff38dSRitesh Harjani ext4_release_io_end(io_end); 193bd2d0210STheodore Ts'o return ret; 194bd2d0210STheodore Ts'o } 195bd2d0210STheodore Ts'o 1962e8fa54eSJan Kara static void dump_completed_IO(struct inode *inode, struct list_head *head) 19728a535f9SDmitry Monakhov { 19828a535f9SDmitry Monakhov #ifdef EXT4FS_DEBUG 19928a535f9SDmitry Monakhov struct list_head *cur, *before, *after; 200821ff38dSRitesh Harjani ext4_io_end_t *io_end, *io_end0, *io_end1; 20128a535f9SDmitry Monakhov 2022e8fa54eSJan Kara if (list_empty(head)) 20328a535f9SDmitry Monakhov return; 20428a535f9SDmitry Monakhov 2052e8fa54eSJan Kara ext4_debug("Dump inode %lu completed io list\n", inode->i_ino); 206821ff38dSRitesh Harjani list_for_each_entry(io_end, head, list) { 207821ff38dSRitesh Harjani cur = &io_end->list; 20828a535f9SDmitry Monakhov before = cur->prev; 209821ff38dSRitesh Harjani io_end0 = container_of(before, ext4_io_end_t, list); 21028a535f9SDmitry Monakhov after = cur->next; 211821ff38dSRitesh Harjani io_end1 = container_of(after, ext4_io_end_t, list); 21228a535f9SDmitry Monakhov 21328a535f9SDmitry Monakhov ext4_debug("io 0x%p from inode %lu,prev 0x%p,next 0x%p\n", 214821ff38dSRitesh Harjani io_end, inode->i_ino, io_end0, io_end1); 21528a535f9SDmitry Monakhov } 21628a535f9SDmitry Monakhov #endif 21728a535f9SDmitry Monakhov } 21828a535f9SDmitry Monakhov 21928a535f9SDmitry Monakhov /* Add the io_end to per-inode completed end_io list. */ 22097a851edSJan Kara static void ext4_add_complete_io(ext4_io_end_t *io_end) 22128a535f9SDmitry Monakhov { 22228a535f9SDmitry Monakhov struct ext4_inode_info *ei = EXT4_I(io_end->inode); 22378371a45SJan Kara struct ext4_sb_info *sbi = EXT4_SB(io_end->inode->i_sb); 22428a535f9SDmitry Monakhov struct workqueue_struct *wq; 22528a535f9SDmitry Monakhov unsigned long flags; 22628a535f9SDmitry Monakhov 2277b7a8665SChristoph Hellwig /* Only reserved conversions from writeback should enter here */ 2287b7a8665SChristoph Hellwig WARN_ON(!(io_end->flag & EXT4_IO_END_UNWRITTEN)); 22978371a45SJan Kara WARN_ON(!io_end->handle && sbi->s_journal); 23028a535f9SDmitry Monakhov spin_lock_irqsave(&ei->i_completed_io_lock, flags); 23178371a45SJan Kara wq = sbi->rsv_conversion_wq; 2322e8fa54eSJan Kara if (list_empty(&ei->i_rsv_conversion_list)) 2332e8fa54eSJan Kara queue_work(wq, &ei->i_rsv_conversion_work); 2342e8fa54eSJan Kara list_add_tail(&io_end->list, &ei->i_rsv_conversion_list); 23528a535f9SDmitry Monakhov spin_unlock_irqrestore(&ei->i_completed_io_lock, flags); 23628a535f9SDmitry Monakhov } 23728a535f9SDmitry Monakhov 2382e8fa54eSJan Kara static int ext4_do_flush_completed_IO(struct inode *inode, 2392e8fa54eSJan Kara struct list_head *head) 24028a535f9SDmitry Monakhov { 241821ff38dSRitesh Harjani ext4_io_end_t *io_end; 242002bd7faSJan Kara struct list_head unwritten; 24328a535f9SDmitry Monakhov unsigned long flags; 24428a535f9SDmitry Monakhov struct ext4_inode_info *ei = EXT4_I(inode); 24528a535f9SDmitry Monakhov int err, ret = 0; 24628a535f9SDmitry Monakhov 24728a535f9SDmitry Monakhov spin_lock_irqsave(&ei->i_completed_io_lock, flags); 2482e8fa54eSJan Kara dump_completed_IO(inode, head); 2492e8fa54eSJan Kara list_replace_init(head, &unwritten); 25028a535f9SDmitry Monakhov spin_unlock_irqrestore(&ei->i_completed_io_lock, flags); 25128a535f9SDmitry Monakhov 25228a535f9SDmitry Monakhov while (!list_empty(&unwritten)) { 253821ff38dSRitesh Harjani io_end = list_entry(unwritten.next, ext4_io_end_t, list); 254821ff38dSRitesh Harjani BUG_ON(!(io_end->flag & EXT4_IO_END_UNWRITTEN)); 255821ff38dSRitesh Harjani list_del_init(&io_end->list); 25628a535f9SDmitry Monakhov 257821ff38dSRitesh Harjani err = ext4_end_io_end(io_end); 25828a535f9SDmitry Monakhov if (unlikely(!ret && err)) 25928a535f9SDmitry Monakhov ret = err; 26028a535f9SDmitry Monakhov } 26128a535f9SDmitry Monakhov return ret; 26228a535f9SDmitry Monakhov } 26328a535f9SDmitry Monakhov 264bd2d0210STheodore Ts'o /* 2652e8fa54eSJan Kara * work on completed IO, to convert unwritten extents to extents 266bd2d0210STheodore Ts'o */ 2672e8fa54eSJan Kara void ext4_end_io_rsv_work(struct work_struct *work) 268bd2d0210STheodore Ts'o { 26984c17543SJan Kara struct ext4_inode_info *ei = container_of(work, struct ext4_inode_info, 2702e8fa54eSJan Kara i_rsv_conversion_work); 2712e8fa54eSJan Kara ext4_do_flush_completed_IO(&ei->vfs_inode, &ei->i_rsv_conversion_list); 2722e8fa54eSJan Kara } 2732e8fa54eSJan Kara 274bd2d0210STheodore Ts'o ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags) 275bd2d0210STheodore Ts'o { 276821ff38dSRitesh Harjani ext4_io_end_t *io_end = kmem_cache_zalloc(io_end_cachep, flags); 277821ff38dSRitesh Harjani 278821ff38dSRitesh Harjani if (io_end) { 279821ff38dSRitesh Harjani io_end->inode = inode; 280821ff38dSRitesh Harjani INIT_LIST_HEAD(&io_end->list); 281c8cc8816SRitesh Harjani INIT_LIST_HEAD(&io_end->list_vec); 28231d21d21SXiyu Yang refcount_set(&io_end->count, 1); 283bd2d0210STheodore Ts'o } 284821ff38dSRitesh Harjani return io_end; 285bd2d0210STheodore Ts'o } 286bd2d0210STheodore Ts'o 28797a851edSJan Kara void ext4_put_io_end_defer(ext4_io_end_t *io_end) 28897a851edSJan Kara { 28931d21d21SXiyu Yang if (refcount_dec_and_test(&io_end->count)) { 290c8cc8816SRitesh Harjani if (!(io_end->flag & EXT4_IO_END_UNWRITTEN) || 291c8cc8816SRitesh Harjani list_empty(&io_end->list_vec)) { 29297a851edSJan Kara ext4_release_io_end(io_end); 29397a851edSJan Kara return; 29497a851edSJan Kara } 29597a851edSJan Kara ext4_add_complete_io(io_end); 29697a851edSJan Kara } 29797a851edSJan Kara } 29897a851edSJan Kara 29997a851edSJan Kara int ext4_put_io_end(ext4_io_end_t *io_end) 30097a851edSJan Kara { 30197a851edSJan Kara int err = 0; 30297a851edSJan Kara 30331d21d21SXiyu Yang if (refcount_dec_and_test(&io_end->count)) { 30497a851edSJan Kara if (io_end->flag & EXT4_IO_END_UNWRITTEN) { 305a00713eaSRitesh Harjani err = ext4_convert_unwritten_io_end_vec(io_end->handle, 306a00713eaSRitesh Harjani io_end); 3076b523df4SJan Kara io_end->handle = NULL; 30897a851edSJan Kara ext4_clear_io_unwritten_flag(io_end); 30997a851edSJan Kara } 31097a851edSJan Kara ext4_release_io_end(io_end); 31197a851edSJan Kara } 31297a851edSJan Kara return err; 31397a851edSJan Kara } 31497a851edSJan Kara 31597a851edSJan Kara ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end) 31697a851edSJan Kara { 31731d21d21SXiyu Yang refcount_inc(&io_end->count); 31897a851edSJan Kara return io_end; 31997a851edSJan Kara } 32097a851edSJan Kara 321822dbba3SJan Kara /* BIO completion function for page writeback */ 3224246a0b6SChristoph Hellwig static void ext4_end_bio(struct bio *bio) 323bd2d0210STheodore Ts'o { 324bd2d0210STheodore Ts'o ext4_io_end_t *io_end = bio->bi_private; 3254f024f37SKent Overstreet sector_t bi_sector = bio->bi_iter.bi_sector; 326bd2d0210STheodore Ts'o 327734294e4SChristoph Hellwig if (WARN_ONCE(!io_end, "io_end is NULL: %pg: sector %Lu len %u err %d\n", 328734294e4SChristoph Hellwig bio->bi_bdev, 32972d622b4STheodore Ts'o (long long) bio->bi_iter.bi_sector, 33072d622b4STheodore Ts'o (unsigned) bio_sectors(bio), 3314e4cbee9SChristoph Hellwig bio->bi_status)) { 33272d622b4STheodore Ts'o ext4_finish_bio(bio); 33372d622b4STheodore Ts'o bio_put(bio); 33472d622b4STheodore Ts'o return; 33572d622b4STheodore Ts'o } 336bd2d0210STheodore Ts'o bio->bi_end_io = NULL; 3370058f965SJan Kara 3384e4cbee9SChristoph Hellwig if (bio->bi_status) { 339b0857d30SJan Kara struct inode *inode = io_end->inode; 340b0857d30SJan Kara 3419503c67cSMatthew Wilcox ext4_warning(inode->i_sb, "I/O error %d writing to inode %lu " 342c8cc8816SRitesh Harjani "starting block %llu)", 3434e4cbee9SChristoph Hellwig bio->bi_status, inode->i_ino, 344f7ad6d2eSTheodore Ts'o (unsigned long long) 345d50bdd5aSCurt Wohlgemuth bi_sector >> (inode->i_blkbits - 9)); 3464e4cbee9SChristoph Hellwig mapping_set_error(inode->i_mapping, 3474e4cbee9SChristoph Hellwig blk_status_to_errno(bio->bi_status)); 348f7ad6d2eSTheodore Ts'o } 349822dbba3SJan Kara 350822dbba3SJan Kara if (io_end->flag & EXT4_IO_END_UNWRITTEN) { 351822dbba3SJan Kara /* 352822dbba3SJan Kara * Link bio into list hanging from io_end. We have to do it 353822dbba3SJan Kara * atomically as bio completions can be racing against each 354822dbba3SJan Kara * other. 355822dbba3SJan Kara */ 356822dbba3SJan Kara bio->bi_private = xchg(&io_end->bio, bio); 35797a851edSJan Kara ext4_put_io_end_defer(io_end); 358822dbba3SJan Kara } else { 359822dbba3SJan Kara /* 360822dbba3SJan Kara * Drop io_end reference early. Inode can get freed once 361822dbba3SJan Kara * we finish the bio. 362822dbba3SJan Kara */ 363822dbba3SJan Kara ext4_put_io_end_defer(io_end); 364822dbba3SJan Kara ext4_finish_bio(bio); 365822dbba3SJan Kara bio_put(bio); 366822dbba3SJan Kara } 367bd2d0210STheodore Ts'o } 368bd2d0210STheodore Ts'o 369bd2d0210STheodore Ts'o void ext4_io_submit(struct ext4_io_submit *io) 370bd2d0210STheodore Ts'o { 371bd2d0210STheodore Ts'o struct bio *bio = io->io_bio; 372bd2d0210STheodore Ts'o 373bd2d0210STheodore Ts'o if (bio) { 3744c4dad11SChristoph Hellwig if (io->io_wbc->sync_mode == WB_SYNC_ALL) 3754c4dad11SChristoph Hellwig io->io_bio->bi_opf |= REQ_SYNC; 3764e49ea4aSMike Christie submit_bio(io->io_bio); 377bd2d0210STheodore Ts'o } 3787dc57615SPeter Huewe io->io_bio = NULL; 37997a851edSJan Kara } 38097a851edSJan Kara 38197a851edSJan Kara void ext4_io_submit_init(struct ext4_io_submit *io, 38297a851edSJan Kara struct writeback_control *wbc) 38397a851edSJan Kara { 3845a33911fSTejun Heo io->io_wbc = wbc; 38597a851edSJan Kara io->io_bio = NULL; 3867dc57615SPeter Huewe io->io_end = NULL; 387bd2d0210STheodore Ts'o } 388bd2d0210STheodore Ts'o 3895500221eSGao Xiang static void io_submit_init_bio(struct ext4_io_submit *io, 390bd2d0210STheodore Ts'o struct buffer_head *bh) 391bd2d0210STheodore Ts'o { 392bd2d0210STheodore Ts'o struct bio *bio; 393bd2d0210STheodore Ts'o 3945500221eSGao Xiang /* 3955500221eSGao Xiang * bio_alloc will _always_ be able to allocate a bio if 3965500221eSGao Xiang * __GFP_DIRECT_RECLAIM is set, see comments for bio_alloc_bioset(). 3975500221eSGao Xiang */ 3984c4dad11SChristoph Hellwig bio = bio_alloc(bh->b_bdev, BIO_MAX_VECS, REQ_OP_WRITE, GFP_NOIO); 3994f74d15fSEric Biggers fscrypt_set_bio_crypt_ctx_bh(bio, bh, GFP_NOIO); 4004f024f37SKent Overstreet bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9); 401bd2d0210STheodore Ts'o bio->bi_end_io = ext4_end_bio; 40297a851edSJan Kara bio->bi_private = ext4_get_io_end(io->io_end); 403bd2d0210STheodore Ts'o io->io_bio = bio; 404bd2d0210STheodore Ts'o io->io_next_block = bh->b_blocknr; 405fd42df30SDennis Zhou wbc_init_bio(io->io_wbc, bio); 406bd2d0210STheodore Ts'o } 407bd2d0210STheodore Ts'o 4085500221eSGao Xiang static void io_submit_add_bh(struct ext4_io_submit *io, 409bd2d0210STheodore Ts'o struct inode *inode, 4102058f83aSMichael Halcrow struct page *page, 411bd2d0210STheodore Ts'o struct buffer_head *bh) 412bd2d0210STheodore Ts'o { 413bd2d0210STheodore Ts'o int ret; 414bd2d0210STheodore Ts'o 4154f74d15fSEric Biggers if (io->io_bio && (bh->b_blocknr != io->io_next_block || 4164f74d15fSEric Biggers !fscrypt_mergeable_bio_bh(io->io_bio, bh))) { 417bd2d0210STheodore Ts'o submit_and_retry: 418bd2d0210STheodore Ts'o ext4_io_submit(io); 419bd2d0210STheodore Ts'o } 420*c75e707fSChristoph Hellwig if (io->io_bio == NULL) 4215500221eSGao Xiang io_submit_init_bio(io, bh); 4222058f83aSMichael Halcrow ret = bio_add_page(io->io_bio, page, bh->b_size, bh_offset(bh)); 423a549984bSTheodore Ts'o if (ret != bh->b_size) 424a549984bSTheodore Ts'o goto submit_and_retry; 42534e51a5eSTejun Heo wbc_account_cgroup_owner(io->io_wbc, page, bh->b_size); 42697a851edSJan Kara io->io_next_block++; 427bd2d0210STheodore Ts'o } 428bd2d0210STheodore Ts'o 429bd2d0210STheodore Ts'o int ext4_bio_write_page(struct ext4_io_submit *io, 430bd2d0210STheodore Ts'o struct page *page, 431bd2d0210STheodore Ts'o int len, 4321c8349a1SNamjae Jeon bool keep_towrite) 433bd2d0210STheodore Ts'o { 434d2d0727bSEric Biggers struct page *bounce_page = NULL; 435bd2d0210STheodore Ts'o struct inode *inode = page->mapping->host; 43618017479SEric Engestrom unsigned block_start; 437bd2d0210STheodore Ts'o struct buffer_head *bh, *head; 438bd2d0210STheodore Ts'o int ret = 0; 4390058f965SJan Kara int nr_submitted = 0; 440937d7b84STheodore Ts'o int nr_to_submit = 0; 441be993933SLei Chen struct writeback_control *wbc = io->io_wbc; 442bd2d0210STheodore Ts'o 443d50bdd5aSCurt Wohlgemuth BUG_ON(!PageLocked(page)); 444bd2d0210STheodore Ts'o BUG_ON(PageWriteback(page)); 445bd2d0210STheodore Ts'o 4461c8349a1SNamjae Jeon if (keep_towrite) 4471c8349a1SNamjae Jeon set_page_writeback_keepwrite(page); 4481c8349a1SNamjae Jeon else 449a54aa761STheodore Ts'o set_page_writeback(page); 450a54aa761STheodore Ts'o ClearPageError(page); 451bd2d0210STheodore Ts'o 4520058f965SJan Kara /* 453f8409abdSLinus Torvalds * Comments copied from block_write_full_page: 454eeece469SJan Kara * 455eeece469SJan Kara * The page straddles i_size. It must be zeroed out on each and every 456eeece469SJan Kara * writepage invocation because it may be mmapped. "A file is mapped 457eeece469SJan Kara * in multiples of the page size. For a file that is not a multiple of 458eeece469SJan Kara * the page size, the remaining memory is zeroed when mapped, and 459eeece469SJan Kara * writes to that region are not written out to the file." 460eeece469SJan Kara */ 46109cbfeafSKirill A. Shutemov if (len < PAGE_SIZE) 46209cbfeafSKirill A. Shutemov zero_user_segment(page, len, PAGE_SIZE); 463eeece469SJan Kara /* 4640058f965SJan Kara * In the first loop we prepare and mark buffers to submit. We have to 4650058f965SJan Kara * mark all buffers in the page before submitting so that 4660058f965SJan Kara * end_page_writeback() cannot be called from ext4_bio_end_io() when IO 4670058f965SJan Kara * on the first buffer finishes and we are still working on submitting 4680058f965SJan Kara * the second buffer. 4690058f965SJan Kara */ 4700058f965SJan Kara bh = head = page_buffers(page); 4710058f965SJan Kara do { 4720058f965SJan Kara block_start = bh_offset(bh); 473bd2d0210STheodore Ts'o if (block_start >= len) { 474bd2d0210STheodore Ts'o clear_buffer_dirty(bh); 475bd2d0210STheodore Ts'o set_buffer_uptodate(bh); 476bd2d0210STheodore Ts'o continue; 477bd2d0210STheodore Ts'o } 4788a850c3fSJan Kara if (!buffer_dirty(bh) || buffer_delay(bh) || 4798a850c3fSJan Kara !buffer_mapped(bh) || buffer_unwritten(bh)) { 4808a850c3fSJan Kara /* A hole? We can safely clear the dirty bit */ 4818a850c3fSJan Kara if (!buffer_mapped(bh)) 4828a850c3fSJan Kara clear_buffer_dirty(bh); 4838a850c3fSJan Kara if (io->io_bio) 4848a850c3fSJan Kara ext4_io_submit(io); 4858a850c3fSJan Kara continue; 4868a850c3fSJan Kara } 48716e08b14Szhangyi (F) if (buffer_new(bh)) 4880058f965SJan Kara clear_buffer_new(bh); 4890058f965SJan Kara set_buffer_async_write(bh); 490937d7b84STheodore Ts'o nr_to_submit++; 4910058f965SJan Kara } while ((bh = bh->b_this_page) != head); 4920058f965SJan Kara 4930058f965SJan Kara bh = head = page_buffers(page); 4942058f83aSMichael Halcrow 4956e4b73bcSEric Biggers /* 4966e4b73bcSEric Biggers * If any blocks are being written to an encrypted file, encrypt them 4976e4b73bcSEric Biggers * into a bounce page. For simplicity, just encrypt until the last 4986e4b73bcSEric Biggers * block which might be needed. This may cause some unneeded blocks 4996e4b73bcSEric Biggers * (e.g. holes) to be unnecessarily encrypted, but this is rare and 5006e4b73bcSEric Biggers * can't happen in the common case of blocksize == PAGE_SIZE. 5016e4b73bcSEric Biggers */ 5024f74d15fSEric Biggers if (fscrypt_inode_uses_fs_layer_crypto(inode) && nr_to_submit) { 503c9af28fdSTheodore Ts'o gfp_t gfp_flags = GFP_NOFS; 5046e4b73bcSEric Biggers unsigned int enc_bytes = round_up(len, i_blocksize(inode)); 505c9af28fdSTheodore Ts'o 506547c556fSEric Biggers /* 507547c556fSEric Biggers * Since bounce page allocation uses a mempool, we can only use 508547c556fSEric Biggers * a waiting mask (i.e. request guaranteed allocation) on the 509547c556fSEric Biggers * first page of the bio. Otherwise it can deadlock. 510547c556fSEric Biggers */ 511547c556fSEric Biggers if (io->io_bio) 512547c556fSEric Biggers gfp_flags = GFP_NOWAIT | __GFP_NOWARN; 513c9af28fdSTheodore Ts'o retry_encrypt: 5146e4b73bcSEric Biggers bounce_page = fscrypt_encrypt_pagecache_blocks(page, enc_bytes, 51553bc1d85SEric Biggers 0, gfp_flags); 516d2d0727bSEric Biggers if (IS_ERR(bounce_page)) { 517d2d0727bSEric Biggers ret = PTR_ERR(bounce_page); 518547c556fSEric Biggers if (ret == -ENOMEM && 519547c556fSEric Biggers (io->io_bio || wbc->sync_mode == WB_SYNC_ALL)) { 5204034247aSNeilBrown gfp_t new_gfp_flags = GFP_NOFS; 521547c556fSEric Biggers if (io->io_bio) 522c9af28fdSTheodore Ts'o ext4_io_submit(io); 523547c556fSEric Biggers else 5244034247aSNeilBrown new_gfp_flags |= __GFP_NOFAIL; 5254034247aSNeilBrown memalloc_retry_wait(gfp_flags); 5264034247aSNeilBrown gfp_flags = new_gfp_flags; 527c9af28fdSTheodore Ts'o goto retry_encrypt; 528c9af28fdSTheodore Ts'o } 5295500221eSGao Xiang 5305500221eSGao Xiang printk_ratelimited(KERN_ERR "%s: ret = %d\n", __func__, ret); 5315500221eSGao Xiang redirty_page_for_writepage(wbc, page); 5325500221eSGao Xiang do { 5335500221eSGao Xiang clear_buffer_async_write(bh); 5345500221eSGao Xiang bh = bh->b_this_page; 5355500221eSGao Xiang } while (bh != head); 5365500221eSGao Xiang goto unlock; 5372058f83aSMichael Halcrow } 5382058f83aSMichael Halcrow } 5392058f83aSMichael Halcrow 5402058f83aSMichael Halcrow /* Now submit buffers to write */ 5410058f965SJan Kara do { 5420058f965SJan Kara if (!buffer_async_write(bh)) 5430058f965SJan Kara continue; 5445500221eSGao Xiang io_submit_add_bh(io, inode, 5455500221eSGao Xiang bounce_page ? bounce_page : page, bh); 5460058f965SJan Kara nr_submitted++; 5471ae48a63SJan Kara clear_buffer_dirty(bh); 5480058f965SJan Kara } while ((bh = bh->b_this_page) != head); 5490058f965SJan Kara 5505500221eSGao Xiang unlock: 551bd2d0210STheodore Ts'o unlock_page(page); 5520058f965SJan Kara /* Nothing submitted - we have to end page writeback */ 5530058f965SJan Kara if (!nr_submitted) 5540058f965SJan Kara end_page_writeback(page); 555bd2d0210STheodore Ts'o return ret; 556bd2d0210STheodore Ts'o } 557