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> 27c9af28fdSTheodore Ts'o #include <linux/backing-dev.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 114b0857d30SJan Kara if (!page) 115b0857d30SJan Kara continue; 116b0857d30SJan Kara 117d2d0727bSEric Biggers if (fscrypt_is_bounce_page(page)) { 118d2d0727bSEric Biggers bounce_page = page; 119d2d0727bSEric Biggers page = fscrypt_pagecache_page(bounce_page); 1202058f83aSMichael Halcrow } 1212058f83aSMichael Halcrow 1224e4cbee9SChristoph Hellwig if (bio->bi_status) { 123b0857d30SJan Kara SetPageError(page); 1245114a97aSMichal Hocko mapping_set_error(page->mapping, -EIO); 125b0857d30SJan Kara } 126b0857d30SJan Kara bh = head = page_buffers(page); 127b0857d30SJan Kara /* 128f1e67e35SThomas Gleixner * We check all buffers in the page under b_uptodate_lock 129b0857d30SJan Kara * to avoid races with other end io clearing async_write flags 130b0857d30SJan Kara */ 131f1e67e35SThomas Gleixner spin_lock_irqsave(&head->b_uptodate_lock, flags); 132b0857d30SJan Kara do { 133b0857d30SJan Kara if (bh_offset(bh) < bio_start || 134b0857d30SJan Kara bh_offset(bh) + bh->b_size > bio_end) { 135b0857d30SJan Kara if (buffer_async_write(bh)) 136b0857d30SJan Kara under_io++; 137b0857d30SJan Kara continue; 138b0857d30SJan Kara } 139b0857d30SJan Kara clear_buffer_async_write(bh); 1404e4cbee9SChristoph Hellwig if (bio->bi_status) 141b0857d30SJan Kara buffer_io_error(bh); 142b0857d30SJan Kara } while ((bh = bh->b_this_page) != head); 143f1e67e35SThomas Gleixner spin_unlock_irqrestore(&head->b_uptodate_lock, flags); 1442058f83aSMichael Halcrow if (!under_io) { 145d2d0727bSEric Biggers fscrypt_free_bounce_page(bounce_page); 146b0857d30SJan Kara end_page_writeback(page); 147b0857d30SJan Kara } 148b0857d30SJan Kara } 1492058f83aSMichael Halcrow } 150b0857d30SJan Kara 15197a851edSJan Kara static void ext4_release_io_end(ext4_io_end_t *io_end) 152bd2d0210STheodore Ts'o { 153b0857d30SJan Kara struct bio *bio, *next_bio; 154b0857d30SJan Kara 15597a851edSJan Kara BUG_ON(!list_empty(&io_end->list)); 15697a851edSJan Kara BUG_ON(io_end->flag & EXT4_IO_END_UNWRITTEN); 1576b523df4SJan Kara WARN_ON(io_end->handle); 158bd2d0210STheodore Ts'o 159b0857d30SJan Kara for (bio = io_end->bio; bio; bio = next_bio) { 160b0857d30SJan Kara next_bio = bio->bi_private; 161b0857d30SJan Kara ext4_finish_bio(bio); 162b0857d30SJan Kara bio_put(bio); 163b0857d30SJan Kara } 164c8cc8816SRitesh Harjani ext4_free_io_end_vec(io_end); 16597a851edSJan Kara kmem_cache_free(io_end_cachep, io_end); 16697a851edSJan Kara } 16797a851edSJan Kara 168a115f749SJan Kara /* 169a115f749SJan Kara * Check a range of space and convert unwritten extents to written. Note that 170a115f749SJan Kara * we are protected from truncate touching same part of extent tree by the 171a115f749SJan Kara * fact that truncate code waits for all DIO to finish (thus exclusion from 172a115f749SJan Kara * direct IO is achieved) and also waits for PageWriteback bits. Thus we 173a115f749SJan Kara * cannot get to ext4_ext_truncate() before all IOs overlapping that range are 174a115f749SJan Kara * completed (happens from ext4_free_ioend()). 175a115f749SJan Kara */ 176821ff38dSRitesh Harjani static int ext4_end_io_end(ext4_io_end_t *io_end) 177bd2d0210STheodore Ts'o { 178821ff38dSRitesh Harjani struct inode *inode = io_end->inode; 179821ff38dSRitesh Harjani handle_t *handle = io_end->handle; 180bd2d0210STheodore Ts'o int ret = 0; 181bd2d0210STheodore Ts'o 182821ff38dSRitesh Harjani ext4_debug("ext4_end_io_nolock: io_end 0x%p from inode %lu,list->next 0x%p," 183bd2d0210STheodore Ts'o "list->prev 0x%p\n", 184821ff38dSRitesh Harjani io_end, inode->i_ino, io_end->list.next, io_end->list.prev); 185bd2d0210STheodore Ts'o 186821ff38dSRitesh Harjani io_end->handle = NULL; /* Following call will use up the handle */ 187a00713eaSRitesh Harjani ret = ext4_convert_unwritten_io_end_vec(handle, io_end); 1880db1ff22STheodore Ts'o if (ret < 0 && !ext4_forced_shutdown(EXT4_SB(inode->i_sb))) { 189b82e384cSTheodore Ts'o ext4_msg(inode->i_sb, KERN_EMERG, 190b82e384cSTheodore Ts'o "failed to convert unwritten extents to written " 191b82e384cSTheodore Ts'o "extents -- potential data loss! " 192c8cc8816SRitesh Harjani "(inode %lu, error %d)", inode->i_ino, ret); 193bd2d0210STheodore Ts'o } 194821ff38dSRitesh Harjani ext4_clear_io_unwritten_flag(io_end); 195821ff38dSRitesh Harjani ext4_release_io_end(io_end); 196bd2d0210STheodore Ts'o return ret; 197bd2d0210STheodore Ts'o } 198bd2d0210STheodore Ts'o 1992e8fa54eSJan Kara static void dump_completed_IO(struct inode *inode, struct list_head *head) 20028a535f9SDmitry Monakhov { 20128a535f9SDmitry Monakhov #ifdef EXT4FS_DEBUG 20228a535f9SDmitry Monakhov struct list_head *cur, *before, *after; 203821ff38dSRitesh Harjani ext4_io_end_t *io_end, *io_end0, *io_end1; 20428a535f9SDmitry Monakhov 2052e8fa54eSJan Kara if (list_empty(head)) 20628a535f9SDmitry Monakhov return; 20728a535f9SDmitry Monakhov 2082e8fa54eSJan Kara ext4_debug("Dump inode %lu completed io list\n", inode->i_ino); 209821ff38dSRitesh Harjani list_for_each_entry(io_end, head, list) { 210821ff38dSRitesh Harjani cur = &io_end->list; 21128a535f9SDmitry Monakhov before = cur->prev; 212821ff38dSRitesh Harjani io_end0 = container_of(before, ext4_io_end_t, list); 21328a535f9SDmitry Monakhov after = cur->next; 214821ff38dSRitesh Harjani io_end1 = container_of(after, ext4_io_end_t, list); 21528a535f9SDmitry Monakhov 21628a535f9SDmitry Monakhov ext4_debug("io 0x%p from inode %lu,prev 0x%p,next 0x%p\n", 217821ff38dSRitesh Harjani io_end, inode->i_ino, io_end0, io_end1); 21828a535f9SDmitry Monakhov } 21928a535f9SDmitry Monakhov #endif 22028a535f9SDmitry Monakhov } 22128a535f9SDmitry Monakhov 22228a535f9SDmitry Monakhov /* Add the io_end to per-inode completed end_io list. */ 22397a851edSJan Kara static void ext4_add_complete_io(ext4_io_end_t *io_end) 22428a535f9SDmitry Monakhov { 22528a535f9SDmitry Monakhov struct ext4_inode_info *ei = EXT4_I(io_end->inode); 22678371a45SJan Kara struct ext4_sb_info *sbi = EXT4_SB(io_end->inode->i_sb); 22728a535f9SDmitry Monakhov struct workqueue_struct *wq; 22828a535f9SDmitry Monakhov unsigned long flags; 22928a535f9SDmitry Monakhov 2307b7a8665SChristoph Hellwig /* Only reserved conversions from writeback should enter here */ 2317b7a8665SChristoph Hellwig WARN_ON(!(io_end->flag & EXT4_IO_END_UNWRITTEN)); 23278371a45SJan Kara WARN_ON(!io_end->handle && sbi->s_journal); 23328a535f9SDmitry Monakhov spin_lock_irqsave(&ei->i_completed_io_lock, flags); 23478371a45SJan Kara wq = sbi->rsv_conversion_wq; 2352e8fa54eSJan Kara if (list_empty(&ei->i_rsv_conversion_list)) 2362e8fa54eSJan Kara queue_work(wq, &ei->i_rsv_conversion_work); 2372e8fa54eSJan Kara list_add_tail(&io_end->list, &ei->i_rsv_conversion_list); 23828a535f9SDmitry Monakhov spin_unlock_irqrestore(&ei->i_completed_io_lock, flags); 23928a535f9SDmitry Monakhov } 24028a535f9SDmitry Monakhov 2412e8fa54eSJan Kara static int ext4_do_flush_completed_IO(struct inode *inode, 2422e8fa54eSJan Kara struct list_head *head) 24328a535f9SDmitry Monakhov { 244821ff38dSRitesh Harjani ext4_io_end_t *io_end; 245002bd7faSJan Kara struct list_head unwritten; 24628a535f9SDmitry Monakhov unsigned long flags; 24728a535f9SDmitry Monakhov struct ext4_inode_info *ei = EXT4_I(inode); 24828a535f9SDmitry Monakhov int err, ret = 0; 24928a535f9SDmitry Monakhov 25028a535f9SDmitry Monakhov spin_lock_irqsave(&ei->i_completed_io_lock, flags); 2512e8fa54eSJan Kara dump_completed_IO(inode, head); 2522e8fa54eSJan Kara list_replace_init(head, &unwritten); 25328a535f9SDmitry Monakhov spin_unlock_irqrestore(&ei->i_completed_io_lock, flags); 25428a535f9SDmitry Monakhov 25528a535f9SDmitry Monakhov while (!list_empty(&unwritten)) { 256821ff38dSRitesh Harjani io_end = list_entry(unwritten.next, ext4_io_end_t, list); 257821ff38dSRitesh Harjani BUG_ON(!(io_end->flag & EXT4_IO_END_UNWRITTEN)); 258821ff38dSRitesh Harjani list_del_init(&io_end->list); 25928a535f9SDmitry Monakhov 260821ff38dSRitesh Harjani err = ext4_end_io_end(io_end); 26128a535f9SDmitry Monakhov if (unlikely(!ret && err)) 26228a535f9SDmitry Monakhov ret = err; 26328a535f9SDmitry Monakhov } 26428a535f9SDmitry Monakhov return ret; 26528a535f9SDmitry Monakhov } 26628a535f9SDmitry Monakhov 267bd2d0210STheodore Ts'o /* 2682e8fa54eSJan Kara * work on completed IO, to convert unwritten extents to extents 269bd2d0210STheodore Ts'o */ 2702e8fa54eSJan Kara void ext4_end_io_rsv_work(struct work_struct *work) 271bd2d0210STheodore Ts'o { 27284c17543SJan Kara struct ext4_inode_info *ei = container_of(work, struct ext4_inode_info, 2732e8fa54eSJan Kara i_rsv_conversion_work); 2742e8fa54eSJan Kara ext4_do_flush_completed_IO(&ei->vfs_inode, &ei->i_rsv_conversion_list); 2752e8fa54eSJan Kara } 2762e8fa54eSJan Kara 277bd2d0210STheodore Ts'o ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags) 278bd2d0210STheodore Ts'o { 279821ff38dSRitesh Harjani ext4_io_end_t *io_end = kmem_cache_zalloc(io_end_cachep, flags); 280821ff38dSRitesh Harjani 281821ff38dSRitesh Harjani if (io_end) { 282821ff38dSRitesh Harjani io_end->inode = inode; 283821ff38dSRitesh Harjani INIT_LIST_HEAD(&io_end->list); 284c8cc8816SRitesh Harjani INIT_LIST_HEAD(&io_end->list_vec); 285821ff38dSRitesh Harjani atomic_set(&io_end->count, 1); 286bd2d0210STheodore Ts'o } 287821ff38dSRitesh Harjani return io_end; 288bd2d0210STheodore Ts'o } 289bd2d0210STheodore Ts'o 29097a851edSJan Kara void ext4_put_io_end_defer(ext4_io_end_t *io_end) 29197a851edSJan Kara { 29297a851edSJan Kara if (atomic_dec_and_test(&io_end->count)) { 293c8cc8816SRitesh Harjani if (!(io_end->flag & EXT4_IO_END_UNWRITTEN) || 294c8cc8816SRitesh Harjani list_empty(&io_end->list_vec)) { 29597a851edSJan Kara ext4_release_io_end(io_end); 29697a851edSJan Kara return; 29797a851edSJan Kara } 29897a851edSJan Kara ext4_add_complete_io(io_end); 29997a851edSJan Kara } 30097a851edSJan Kara } 30197a851edSJan Kara 30297a851edSJan Kara int ext4_put_io_end(ext4_io_end_t *io_end) 30397a851edSJan Kara { 30497a851edSJan Kara int err = 0; 30597a851edSJan Kara 30697a851edSJan Kara if (atomic_dec_and_test(&io_end->count)) { 30797a851edSJan Kara if (io_end->flag & EXT4_IO_END_UNWRITTEN) { 308a00713eaSRitesh Harjani err = ext4_convert_unwritten_io_end_vec(io_end->handle, 309a00713eaSRitesh Harjani io_end); 3106b523df4SJan Kara io_end->handle = NULL; 31197a851edSJan Kara ext4_clear_io_unwritten_flag(io_end); 31297a851edSJan Kara } 31397a851edSJan Kara ext4_release_io_end(io_end); 31497a851edSJan Kara } 31597a851edSJan Kara return err; 31697a851edSJan Kara } 31797a851edSJan Kara 31897a851edSJan Kara ext4_io_end_t *ext4_get_io_end(ext4_io_end_t *io_end) 31997a851edSJan Kara { 32097a851edSJan Kara atomic_inc(&io_end->count); 32197a851edSJan Kara return io_end; 32297a851edSJan Kara } 32397a851edSJan Kara 324822dbba3SJan Kara /* BIO completion function for page writeback */ 3254246a0b6SChristoph Hellwig static void ext4_end_bio(struct bio *bio) 326bd2d0210STheodore Ts'o { 327bd2d0210STheodore Ts'o ext4_io_end_t *io_end = bio->bi_private; 3284f024f37SKent Overstreet sector_t bi_sector = bio->bi_iter.bi_sector; 32972d622b4STheodore Ts'o char b[BDEVNAME_SIZE]; 330bd2d0210STheodore Ts'o 33172d622b4STheodore Ts'o if (WARN_ONCE(!io_end, "io_end is NULL: %s: sector %Lu len %u err %d\n", 33274d46992SChristoph Hellwig bio_devname(bio, b), 33372d622b4STheodore Ts'o (long long) bio->bi_iter.bi_sector, 33472d622b4STheodore Ts'o (unsigned) bio_sectors(bio), 3354e4cbee9SChristoph Hellwig bio->bi_status)) { 33672d622b4STheodore Ts'o ext4_finish_bio(bio); 33772d622b4STheodore Ts'o bio_put(bio); 33872d622b4STheodore Ts'o return; 33972d622b4STheodore Ts'o } 340bd2d0210STheodore Ts'o bio->bi_end_io = NULL; 3410058f965SJan Kara 3424e4cbee9SChristoph Hellwig if (bio->bi_status) { 343b0857d30SJan Kara struct inode *inode = io_end->inode; 344b0857d30SJan Kara 3459503c67cSMatthew Wilcox ext4_warning(inode->i_sb, "I/O error %d writing to inode %lu " 346c8cc8816SRitesh Harjani "starting block %llu)", 3474e4cbee9SChristoph Hellwig bio->bi_status, inode->i_ino, 348f7ad6d2eSTheodore Ts'o (unsigned long long) 349d50bdd5aSCurt Wohlgemuth bi_sector >> (inode->i_blkbits - 9)); 3504e4cbee9SChristoph Hellwig mapping_set_error(inode->i_mapping, 3514e4cbee9SChristoph Hellwig blk_status_to_errno(bio->bi_status)); 352f7ad6d2eSTheodore Ts'o } 353822dbba3SJan Kara 354822dbba3SJan Kara if (io_end->flag & EXT4_IO_END_UNWRITTEN) { 355822dbba3SJan Kara /* 356822dbba3SJan Kara * Link bio into list hanging from io_end. We have to do it 357822dbba3SJan Kara * atomically as bio completions can be racing against each 358822dbba3SJan Kara * other. 359822dbba3SJan Kara */ 360822dbba3SJan Kara bio->bi_private = xchg(&io_end->bio, bio); 36197a851edSJan Kara ext4_put_io_end_defer(io_end); 362822dbba3SJan Kara } else { 363822dbba3SJan Kara /* 364822dbba3SJan Kara * Drop io_end reference early. Inode can get freed once 365822dbba3SJan Kara * we finish the bio. 366822dbba3SJan Kara */ 367822dbba3SJan Kara ext4_put_io_end_defer(io_end); 368822dbba3SJan Kara ext4_finish_bio(bio); 369822dbba3SJan Kara bio_put(bio); 370822dbba3SJan Kara } 371bd2d0210STheodore Ts'o } 372bd2d0210STheodore Ts'o 373bd2d0210STheodore Ts'o void ext4_io_submit(struct ext4_io_submit *io) 374bd2d0210STheodore Ts'o { 375bd2d0210STheodore Ts'o struct bio *bio = io->io_bio; 376bd2d0210STheodore Ts'o 377bd2d0210STheodore Ts'o if (bio) { 37895fe6c1aSMike Christie int io_op_flags = io->io_wbc->sync_mode == WB_SYNC_ALL ? 37970fd7614SChristoph Hellwig REQ_SYNC : 0; 3800127251cSJens Axboe io->io_bio->bi_write_hint = io->io_end->inode->i_write_hint; 38195fe6c1aSMike Christie bio_set_op_attrs(io->io_bio, REQ_OP_WRITE, io_op_flags); 3824e49ea4aSMike Christie submit_bio(io->io_bio); 383bd2d0210STheodore Ts'o } 3847dc57615SPeter Huewe io->io_bio = NULL; 38597a851edSJan Kara } 38697a851edSJan Kara 38797a851edSJan Kara void ext4_io_submit_init(struct ext4_io_submit *io, 38897a851edSJan Kara struct writeback_control *wbc) 38997a851edSJan Kara { 3905a33911fSTejun Heo io->io_wbc = wbc; 39197a851edSJan Kara io->io_bio = NULL; 3927dc57615SPeter Huewe io->io_end = NULL; 393bd2d0210STheodore Ts'o } 394bd2d0210STheodore Ts'o 3955500221eSGao Xiang static void io_submit_init_bio(struct ext4_io_submit *io, 396bd2d0210STheodore Ts'o struct buffer_head *bh) 397bd2d0210STheodore Ts'o { 398bd2d0210STheodore Ts'o struct bio *bio; 399bd2d0210STheodore Ts'o 4005500221eSGao Xiang /* 4015500221eSGao Xiang * bio_alloc will _always_ be able to allocate a bio if 4025500221eSGao Xiang * __GFP_DIRECT_RECLAIM is set, see comments for bio_alloc_bioset(). 4035500221eSGao Xiang */ 404b54ffb73SKent Overstreet bio = bio_alloc(GFP_NOIO, BIO_MAX_PAGES); 405*4f74d15fSEric Biggers fscrypt_set_bio_crypt_ctx_bh(bio, bh, GFP_NOIO); 4064f024f37SKent Overstreet bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9); 40774d46992SChristoph Hellwig bio_set_dev(bio, bh->b_bdev); 408bd2d0210STheodore Ts'o bio->bi_end_io = ext4_end_bio; 40997a851edSJan Kara bio->bi_private = ext4_get_io_end(io->io_end); 410bd2d0210STheodore Ts'o io->io_bio = bio; 411bd2d0210STheodore Ts'o io->io_next_block = bh->b_blocknr; 412fd42df30SDennis Zhou wbc_init_bio(io->io_wbc, bio); 413bd2d0210STheodore Ts'o } 414bd2d0210STheodore Ts'o 4155500221eSGao Xiang static void io_submit_add_bh(struct ext4_io_submit *io, 416bd2d0210STheodore Ts'o struct inode *inode, 4172058f83aSMichael Halcrow struct page *page, 418bd2d0210STheodore Ts'o struct buffer_head *bh) 419bd2d0210STheodore Ts'o { 420bd2d0210STheodore Ts'o int ret; 421bd2d0210STheodore Ts'o 422*4f74d15fSEric Biggers if (io->io_bio && (bh->b_blocknr != io->io_next_block || 423*4f74d15fSEric Biggers !fscrypt_mergeable_bio_bh(io->io_bio, bh))) { 424bd2d0210STheodore Ts'o submit_and_retry: 425bd2d0210STheodore Ts'o ext4_io_submit(io); 426bd2d0210STheodore Ts'o } 427bd2d0210STheodore Ts'o if (io->io_bio == NULL) { 4285500221eSGao Xiang io_submit_init_bio(io, bh); 4290127251cSJens Axboe io->io_bio->bi_write_hint = inode->i_write_hint; 430bd2d0210STheodore Ts'o } 4312058f83aSMichael Halcrow ret = bio_add_page(io->io_bio, page, bh->b_size, bh_offset(bh)); 432a549984bSTheodore Ts'o if (ret != bh->b_size) 433a549984bSTheodore Ts'o goto submit_and_retry; 43434e51a5eSTejun Heo wbc_account_cgroup_owner(io->io_wbc, page, bh->b_size); 43597a851edSJan Kara io->io_next_block++; 436bd2d0210STheodore Ts'o } 437bd2d0210STheodore Ts'o 438bd2d0210STheodore Ts'o int ext4_bio_write_page(struct ext4_io_submit *io, 439bd2d0210STheodore Ts'o struct page *page, 440bd2d0210STheodore Ts'o int len, 4411c8349a1SNamjae Jeon struct writeback_control *wbc, 4421c8349a1SNamjae Jeon bool keep_towrite) 443bd2d0210STheodore Ts'o { 444d2d0727bSEric Biggers struct page *bounce_page = NULL; 445bd2d0210STheodore Ts'o struct inode *inode = page->mapping->host; 44618017479SEric Engestrom unsigned block_start; 447bd2d0210STheodore Ts'o struct buffer_head *bh, *head; 448bd2d0210STheodore Ts'o int ret = 0; 4490058f965SJan Kara int nr_submitted = 0; 450937d7b84STheodore Ts'o int nr_to_submit = 0; 451bd2d0210STheodore Ts'o 452d50bdd5aSCurt Wohlgemuth BUG_ON(!PageLocked(page)); 453bd2d0210STheodore Ts'o BUG_ON(PageWriteback(page)); 454bd2d0210STheodore Ts'o 4551c8349a1SNamjae Jeon if (keep_towrite) 4561c8349a1SNamjae Jeon set_page_writeback_keepwrite(page); 4571c8349a1SNamjae Jeon else 458a54aa761STheodore Ts'o set_page_writeback(page); 459a54aa761STheodore Ts'o ClearPageError(page); 460bd2d0210STheodore Ts'o 4610058f965SJan Kara /* 462f8409abdSLinus Torvalds * Comments copied from block_write_full_page: 463eeece469SJan Kara * 464eeece469SJan Kara * The page straddles i_size. It must be zeroed out on each and every 465eeece469SJan Kara * writepage invocation because it may be mmapped. "A file is mapped 466eeece469SJan Kara * in multiples of the page size. For a file that is not a multiple of 467eeece469SJan Kara * the page size, the remaining memory is zeroed when mapped, and 468eeece469SJan Kara * writes to that region are not written out to the file." 469eeece469SJan Kara */ 47009cbfeafSKirill A. Shutemov if (len < PAGE_SIZE) 47109cbfeafSKirill A. Shutemov zero_user_segment(page, len, PAGE_SIZE); 472eeece469SJan Kara /* 4730058f965SJan Kara * In the first loop we prepare and mark buffers to submit. We have to 4740058f965SJan Kara * mark all buffers in the page before submitting so that 4750058f965SJan Kara * end_page_writeback() cannot be called from ext4_bio_end_io() when IO 4760058f965SJan Kara * on the first buffer finishes and we are still working on submitting 4770058f965SJan Kara * the second buffer. 4780058f965SJan Kara */ 4790058f965SJan Kara bh = head = page_buffers(page); 4800058f965SJan Kara do { 4810058f965SJan Kara block_start = bh_offset(bh); 482bd2d0210STheodore Ts'o if (block_start >= len) { 483bd2d0210STheodore Ts'o clear_buffer_dirty(bh); 484bd2d0210STheodore Ts'o set_buffer_uptodate(bh); 485bd2d0210STheodore Ts'o continue; 486bd2d0210STheodore Ts'o } 4878a850c3fSJan Kara if (!buffer_dirty(bh) || buffer_delay(bh) || 4888a850c3fSJan Kara !buffer_mapped(bh) || buffer_unwritten(bh)) { 4898a850c3fSJan Kara /* A hole? We can safely clear the dirty bit */ 4908a850c3fSJan Kara if (!buffer_mapped(bh)) 4918a850c3fSJan Kara clear_buffer_dirty(bh); 4928a850c3fSJan Kara if (io->io_bio) 4938a850c3fSJan Kara ext4_io_submit(io); 4948a850c3fSJan Kara continue; 4958a850c3fSJan Kara } 49616e08b14Szhangyi (F) if (buffer_new(bh)) 4970058f965SJan Kara clear_buffer_new(bh); 4980058f965SJan Kara set_buffer_async_write(bh); 499937d7b84STheodore Ts'o nr_to_submit++; 5000058f965SJan Kara } while ((bh = bh->b_this_page) != head); 5010058f965SJan Kara 5020058f965SJan Kara bh = head = page_buffers(page); 5032058f83aSMichael Halcrow 5046e4b73bcSEric Biggers /* 5056e4b73bcSEric Biggers * If any blocks are being written to an encrypted file, encrypt them 5066e4b73bcSEric Biggers * into a bounce page. For simplicity, just encrypt until the last 5076e4b73bcSEric Biggers * block which might be needed. This may cause some unneeded blocks 5086e4b73bcSEric Biggers * (e.g. holes) to be unnecessarily encrypted, but this is rare and 5096e4b73bcSEric Biggers * can't happen in the common case of blocksize == PAGE_SIZE. 5106e4b73bcSEric Biggers */ 511*4f74d15fSEric Biggers if (fscrypt_inode_uses_fs_layer_crypto(inode) && nr_to_submit) { 512c9af28fdSTheodore Ts'o gfp_t gfp_flags = GFP_NOFS; 5136e4b73bcSEric Biggers unsigned int enc_bytes = round_up(len, i_blocksize(inode)); 514c9af28fdSTheodore Ts'o 515547c556fSEric Biggers /* 516547c556fSEric Biggers * Since bounce page allocation uses a mempool, we can only use 517547c556fSEric Biggers * a waiting mask (i.e. request guaranteed allocation) on the 518547c556fSEric Biggers * first page of the bio. Otherwise it can deadlock. 519547c556fSEric Biggers */ 520547c556fSEric Biggers if (io->io_bio) 521547c556fSEric Biggers gfp_flags = GFP_NOWAIT | __GFP_NOWARN; 522c9af28fdSTheodore Ts'o retry_encrypt: 5236e4b73bcSEric Biggers bounce_page = fscrypt_encrypt_pagecache_blocks(page, enc_bytes, 52453bc1d85SEric Biggers 0, gfp_flags); 525d2d0727bSEric Biggers if (IS_ERR(bounce_page)) { 526d2d0727bSEric Biggers ret = PTR_ERR(bounce_page); 527547c556fSEric Biggers if (ret == -ENOMEM && 528547c556fSEric Biggers (io->io_bio || wbc->sync_mode == WB_SYNC_ALL)) { 529547c556fSEric Biggers gfp_flags = GFP_NOFS; 530547c556fSEric Biggers if (io->io_bio) 531c9af28fdSTheodore Ts'o ext4_io_submit(io); 532547c556fSEric Biggers else 533c9af28fdSTheodore Ts'o gfp_flags |= __GFP_NOFAIL; 534547c556fSEric Biggers congestion_wait(BLK_RW_ASYNC, HZ/50); 535c9af28fdSTheodore Ts'o goto retry_encrypt; 536c9af28fdSTheodore Ts'o } 5375500221eSGao Xiang 5385500221eSGao Xiang printk_ratelimited(KERN_ERR "%s: ret = %d\n", __func__, ret); 5395500221eSGao Xiang redirty_page_for_writepage(wbc, page); 5405500221eSGao Xiang do { 5415500221eSGao Xiang clear_buffer_async_write(bh); 5425500221eSGao Xiang bh = bh->b_this_page; 5435500221eSGao Xiang } while (bh != head); 5445500221eSGao Xiang goto unlock; 5452058f83aSMichael Halcrow } 5462058f83aSMichael Halcrow } 5472058f83aSMichael Halcrow 5482058f83aSMichael Halcrow /* Now submit buffers to write */ 5490058f965SJan Kara do { 5500058f965SJan Kara if (!buffer_async_write(bh)) 5510058f965SJan Kara continue; 5525500221eSGao Xiang io_submit_add_bh(io, inode, 5535500221eSGao Xiang bounce_page ? bounce_page : page, bh); 5540058f965SJan Kara nr_submitted++; 5551ae48a63SJan Kara clear_buffer_dirty(bh); 5560058f965SJan Kara } while ((bh = bh->b_this_page) != head); 5570058f965SJan Kara 5585500221eSGao Xiang unlock: 559bd2d0210STheodore Ts'o unlock_page(page); 5600058f965SJan Kara /* Nothing submitted - we have to end page writeback */ 5610058f965SJan Kara if (!nr_submitted) 5620058f965SJan Kara end_page_writeback(page); 563bd2d0210STheodore Ts'o return ret; 564bd2d0210STheodore Ts'o } 565