diff options
Diffstat (limited to 'fs/btrfs/bio.c')
| -rw-r--r-- | fs/btrfs/bio.c | 1059 |
1 files changed, 1059 insertions, 0 deletions
diff --git a/fs/btrfs/bio.c b/fs/btrfs/bio.c new file mode 100644 index 000000000000..fa1d321a2fb8 --- /dev/null +++ b/fs/btrfs/bio.c @@ -0,0 +1,1059 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2007 Oracle. All rights reserved. + * Copyright (C) 2022 Christoph Hellwig. + */ + +#include <linux/bio.h> +#include "bio.h" +#include "ctree.h" +#include "volumes.h" +#include "raid56.h" +#include "async-thread.h" +#include "dev-replace.h" +#include "zoned.h" +#include "file-item.h" +#include "raid-stripe-tree.h" + +static struct bio_set btrfs_bioset; +static struct bio_set btrfs_clone_bioset; +static struct bio_set btrfs_repair_bioset; +static mempool_t btrfs_failed_bio_pool; + +struct btrfs_failed_bio { + struct btrfs_bio *bbio; + int num_copies; + atomic_t repair_count; +}; + +/* Is this a data path I/O that needs storage layer checksum and repair? */ +static inline bool is_data_bbio(const struct btrfs_bio *bbio) +{ + return bbio->inode && is_data_inode(bbio->inode); +} + +static bool bbio_has_ordered_extent(const struct btrfs_bio *bbio) +{ + return is_data_bbio(bbio) && btrfs_op(&bbio->bio) == BTRFS_MAP_WRITE; +} + +/* + * Initialize a btrfs_bio structure. This skips the embedded bio itself as it + * is already initialized by the block layer. + */ +void btrfs_bio_init(struct btrfs_bio *bbio, struct btrfs_inode *inode, u64 file_offset, + btrfs_bio_end_io_t end_io, void *private) +{ + /* @inode parameter is mandatory. */ + ASSERT(inode); + + memset(bbio, 0, offsetof(struct btrfs_bio, bio)); + bbio->inode = inode; + bbio->end_io = end_io; + bbio->private = private; + bbio->file_offset = file_offset; + atomic_set(&bbio->pending_ios, 1); + WRITE_ONCE(bbio->status, BLK_STS_OK); +} + +/* + * Allocate a btrfs_bio structure. The btrfs_bio is the main I/O container for + * btrfs, and is used for all I/O submitted through btrfs_submit_bbio(). + * + * Just like the underlying bio_alloc_bioset it will not fail as it is backed by + * a mempool. + */ +struct btrfs_bio *btrfs_bio_alloc(unsigned int nr_vecs, blk_opf_t opf, + struct btrfs_inode *inode, u64 file_offset, + btrfs_bio_end_io_t end_io, void *private) +{ + struct btrfs_bio *bbio; + struct bio *bio; + + bio = bio_alloc_bioset(NULL, nr_vecs, opf, GFP_NOFS, &btrfs_bioset); + bbio = btrfs_bio(bio); + btrfs_bio_init(bbio, inode, file_offset, end_io, private); + return bbio; +} + +static struct btrfs_bio *btrfs_split_bio(struct btrfs_fs_info *fs_info, + struct btrfs_bio *orig_bbio, + u64 map_length) +{ + struct btrfs_bio *bbio; + struct bio *bio; + + bio = bio_split(&orig_bbio->bio, map_length >> SECTOR_SHIFT, GFP_NOFS, + &btrfs_clone_bioset); + if (IS_ERR(bio)) + return ERR_CAST(bio); + + bbio = btrfs_bio(bio); + btrfs_bio_init(bbio, orig_bbio->inode, orig_bbio->file_offset, NULL, orig_bbio); + orig_bbio->file_offset += map_length; + if (bbio_has_ordered_extent(bbio)) { + refcount_inc(&orig_bbio->ordered->refs); + bbio->ordered = orig_bbio->ordered; + bbio->orig_logical = orig_bbio->orig_logical; + orig_bbio->orig_logical += map_length; + } + bbio->csum_search_commit_root = orig_bbio->csum_search_commit_root; + atomic_inc(&orig_bbio->pending_ios); + return bbio; +} + +void btrfs_bio_end_io(struct btrfs_bio *bbio, blk_status_t status) +{ + /* Make sure we're already in task context. */ + ASSERT(in_task()); + + if (bbio->async_csum) + wait_for_completion(&bbio->csum_done); + + bbio->bio.bi_status = status; + if (bbio->bio.bi_pool == &btrfs_clone_bioset) { + struct btrfs_bio *orig_bbio = bbio->private; + + /* Free bio that was never submitted to the underlying device. */ + if (bbio_has_ordered_extent(bbio)) + btrfs_put_ordered_extent(bbio->ordered); + bio_put(&bbio->bio); + + bbio = orig_bbio; + } + + /* + * At this point, bbio always points to the original btrfs_bio. Save + * the first error in it. + */ + if (status != BLK_STS_OK) + cmpxchg(&bbio->status, BLK_STS_OK, status); + + if (atomic_dec_and_test(&bbio->pending_ios)) { + /* Load split bio's error which might be set above. */ + if (status == BLK_STS_OK) + bbio->bio.bi_status = READ_ONCE(bbio->status); + + if (bbio_has_ordered_extent(bbio)) { + struct btrfs_ordered_extent *ordered = bbio->ordered; + + bbio->end_io(bbio); + btrfs_put_ordered_extent(ordered); + } else { + bbio->end_io(bbio); + } + } +} + +static int next_repair_mirror(const struct btrfs_failed_bio *fbio, int cur_mirror) +{ + if (cur_mirror == fbio->num_copies) + return cur_mirror + 1 - fbio->num_copies; + return cur_mirror + 1; +} + +static int prev_repair_mirror(const struct btrfs_failed_bio *fbio, int cur_mirror) +{ + if (cur_mirror == 1) + return fbio->num_copies; + return cur_mirror - 1; +} + +static void btrfs_repair_done(struct btrfs_failed_bio *fbio) +{ + if (atomic_dec_and_test(&fbio->repair_count)) { + btrfs_bio_end_io(fbio->bbio, fbio->bbio->bio.bi_status); + mempool_free(fbio, &btrfs_failed_bio_pool); + } +} + +static void btrfs_end_repair_bio(struct btrfs_bio *repair_bbio, + struct btrfs_device *dev) +{ + struct btrfs_failed_bio *fbio = repair_bbio->private; + struct btrfs_inode *inode = repair_bbio->inode; + struct btrfs_fs_info *fs_info = inode->root->fs_info; + /* + * We can not move forward the saved_iter, as it will be later + * utilized by repair_bbio again. + */ + struct bvec_iter saved_iter = repair_bbio->saved_iter; + const u32 step = min(fs_info->sectorsize, PAGE_SIZE); + const u64 logical = repair_bbio->saved_iter.bi_sector << SECTOR_SHIFT; + const u32 nr_steps = repair_bbio->saved_iter.bi_size / step; + int mirror = repair_bbio->mirror_num; + phys_addr_t paddrs[BTRFS_MAX_BLOCKSIZE / PAGE_SIZE]; + phys_addr_t paddr; + unsigned int slot = 0; + + /* Repair bbio should be eaxctly one block sized. */ + ASSERT(repair_bbio->saved_iter.bi_size == fs_info->sectorsize); + + btrfs_bio_for_each_block(paddr, &repair_bbio->bio, &saved_iter, step) { + ASSERT(slot < nr_steps); + paddrs[slot] = paddr; + slot++; + } + + if (repair_bbio->bio.bi_status || + !btrfs_data_csum_ok(repair_bbio, dev, 0, paddrs)) { + bio_reset(&repair_bbio->bio, NULL, REQ_OP_READ); + repair_bbio->bio.bi_iter = repair_bbio->saved_iter; + + mirror = next_repair_mirror(fbio, mirror); + if (mirror == fbio->bbio->mirror_num) { + btrfs_debug(fs_info, "no mirror left"); + fbio->bbio->bio.bi_status = BLK_STS_IOERR; + goto done; + } + + btrfs_submit_bbio(repair_bbio, mirror); + return; + } + + do { + mirror = prev_repair_mirror(fbio, mirror); + btrfs_repair_io_failure(fs_info, btrfs_ino(inode), + repair_bbio->file_offset, fs_info->sectorsize, + logical, paddrs, step, mirror); + } while (mirror != fbio->bbio->mirror_num); + +done: + btrfs_repair_done(fbio); + bio_put(&repair_bbio->bio); +} + +/* + * Try to kick off a repair read to the next available mirror for a bad sector. + * + * This primarily tries to recover good data to serve the actual read request, + * but also tries to write the good data back to the bad mirror(s) when a + * read succeeded to restore the redundancy. + */ +static struct btrfs_failed_bio *repair_one_sector(struct btrfs_bio *failed_bbio, + u32 bio_offset, + phys_addr_t paddrs[], + struct btrfs_failed_bio *fbio) +{ + struct btrfs_inode *inode = failed_bbio->inode; + struct btrfs_fs_info *fs_info = inode->root->fs_info; + const u32 sectorsize = fs_info->sectorsize; + const u32 step = min(fs_info->sectorsize, PAGE_SIZE); + const u32 nr_steps = sectorsize / step; + /* + * For bs > ps cases, the saved_iter can be partially moved forward. + * In that case we should round it down to the block boundary. + */ + const u64 logical = round_down(failed_bbio->saved_iter.bi_sector << SECTOR_SHIFT, + sectorsize); + struct btrfs_bio *repair_bbio; + struct bio *repair_bio; + int num_copies; + int mirror; + + btrfs_debug(fs_info, "repair read error: read error at %llu", + failed_bbio->file_offset + bio_offset); + + num_copies = btrfs_num_copies(fs_info, logical, sectorsize); + if (num_copies == 1) { + btrfs_debug(fs_info, "no copy to repair from"); + failed_bbio->bio.bi_status = BLK_STS_IOERR; + return fbio; + } + + if (!fbio) { + fbio = mempool_alloc(&btrfs_failed_bio_pool, GFP_NOFS); + fbio->bbio = failed_bbio; + fbio->num_copies = num_copies; + atomic_set(&fbio->repair_count, 1); + } + + atomic_inc(&fbio->repair_count); + + repair_bio = bio_alloc_bioset(NULL, nr_steps, REQ_OP_READ, GFP_NOFS, + &btrfs_repair_bioset); + repair_bio->bi_iter.bi_sector = logical >> SECTOR_SHIFT; + for (int i = 0; i < nr_steps; i++) { + int ret; + + ASSERT(offset_in_page(paddrs[i]) + step <= PAGE_SIZE); + + ret = bio_add_page(repair_bio, phys_to_page(paddrs[i]), step, + offset_in_page(paddrs[i])); + ASSERT(ret == step); + } + + repair_bbio = btrfs_bio(repair_bio); + btrfs_bio_init(repair_bbio, failed_bbio->inode, failed_bbio->file_offset + bio_offset, + NULL, fbio); + + mirror = next_repair_mirror(fbio, failed_bbio->mirror_num); + btrfs_debug(fs_info, "submitting repair read to mirror %d", mirror); + btrfs_submit_bbio(repair_bbio, mirror); + return fbio; +} + +static void btrfs_check_read_bio(struct btrfs_bio *bbio, struct btrfs_device *dev) +{ + struct btrfs_inode *inode = bbio->inode; + struct btrfs_fs_info *fs_info = inode->root->fs_info; + const u32 sectorsize = fs_info->sectorsize; + const u32 step = min(sectorsize, PAGE_SIZE); + const u32 nr_steps = sectorsize / step; + struct bvec_iter *iter = &bbio->saved_iter; + blk_status_t status = bbio->bio.bi_status; + struct btrfs_failed_bio *fbio = NULL; + phys_addr_t paddrs[BTRFS_MAX_BLOCKSIZE / PAGE_SIZE]; + phys_addr_t paddr; + u32 offset = 0; + + /* Read-repair requires the inode field to be set by the submitter. */ + ASSERT(inode); + + /* + * Hand off repair bios to the repair code as there is no upper level + * submitter for them. + */ + if (bbio->bio.bi_pool == &btrfs_repair_bioset) { + btrfs_end_repair_bio(bbio, dev); + return; + } + + /* Clear the I/O error. A failed repair will reset it. */ + bbio->bio.bi_status = BLK_STS_OK; + + btrfs_bio_for_each_block(paddr, &bbio->bio, iter, step) { + paddrs[(offset / step) % nr_steps] = paddr; + offset += step; + + if (IS_ALIGNED(offset, sectorsize)) { + if (status || + !btrfs_data_csum_ok(bbio, dev, offset - sectorsize, paddrs)) + fbio = repair_one_sector(bbio, offset - sectorsize, + paddrs, fbio); + } + } + if (bbio->csum != bbio->csum_inline) + kvfree(bbio->csum); + + if (fbio) + btrfs_repair_done(fbio); + else + btrfs_bio_end_io(bbio, bbio->bio.bi_status); +} + +static void btrfs_log_dev_io_error(const struct bio *bio, struct btrfs_device *dev) +{ + if (!dev || !dev->bdev) + return; + if (bio->bi_status != BLK_STS_IOERR && bio->bi_status != BLK_STS_TARGET) + return; + + if (btrfs_op(bio) == BTRFS_MAP_WRITE) + btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_WRITE_ERRS); + else if (!(bio->bi_opf & REQ_RAHEAD)) + btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_READ_ERRS); + if (bio->bi_opf & REQ_PREFLUSH) + btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_FLUSH_ERRS); +} + +static struct workqueue_struct *btrfs_end_io_wq(const struct btrfs_fs_info *fs_info, + const struct bio *bio) +{ + if (bio->bi_opf & REQ_META) + return fs_info->endio_meta_workers; + return fs_info->endio_workers; +} + +static void simple_end_io_work(struct work_struct *work) +{ + struct btrfs_bio *bbio = container_of(work, struct btrfs_bio, end_io_work); + struct bio *bio = &bbio->bio; + + if (bio_op(bio) == REQ_OP_READ) { + /* Metadata reads are checked and repaired by the submitter. */ + if (is_data_bbio(bbio)) + return btrfs_check_read_bio(bbio, bbio->bio.bi_private); + return btrfs_bio_end_io(bbio, bbio->bio.bi_status); + } + if (bio_is_zone_append(bio) && !bio->bi_status) + btrfs_record_physical_zoned(bbio); + btrfs_bio_end_io(bbio, bbio->bio.bi_status); +} + +static void btrfs_simple_end_io(struct bio *bio) +{ + struct btrfs_bio *bbio = btrfs_bio(bio); + struct btrfs_device *dev = bio->bi_private; + struct btrfs_fs_info *fs_info = bbio->inode->root->fs_info; + + btrfs_bio_counter_dec(fs_info); + + if (bio->bi_status) + btrfs_log_dev_io_error(bio, dev); + + INIT_WORK(&bbio->end_io_work, simple_end_io_work); + queue_work(btrfs_end_io_wq(fs_info, bio), &bbio->end_io_work); +} + +static void btrfs_raid56_end_io(struct bio *bio) +{ + struct btrfs_io_context *bioc = bio->bi_private; + struct btrfs_bio *bbio = btrfs_bio(bio); + + /* RAID56 endio is always handled in workqueue. */ + ASSERT(in_task()); + + btrfs_bio_counter_dec(bioc->fs_info); + bbio->mirror_num = bioc->mirror_num; + if (bio_op(bio) == REQ_OP_READ && is_data_bbio(bbio)) + btrfs_check_read_bio(bbio, NULL); + else + btrfs_bio_end_io(bbio, bbio->bio.bi_status); + + btrfs_put_bioc(bioc); +} + +static void orig_write_end_io_work(struct work_struct *work) +{ + struct btrfs_bio *bbio = container_of(work, struct btrfs_bio, end_io_work); + struct bio *bio = &bbio->bio; + struct btrfs_io_stripe *stripe = bio->bi_private; + struct btrfs_io_context *bioc = stripe->bioc; + + btrfs_bio_counter_dec(bioc->fs_info); + + if (bio->bi_status) { + atomic_inc(&bioc->error); + btrfs_log_dev_io_error(bio, stripe->dev); + } + + /* + * Only send an error to the higher layers if it is beyond the tolerance + * threshold. + */ + if (atomic_read(&bioc->error) > bioc->max_errors) + bio->bi_status = BLK_STS_IOERR; + else + bio->bi_status = BLK_STS_OK; + + if (bio_is_zone_append(bio) && !bio->bi_status) + stripe->physical = bio->bi_iter.bi_sector << SECTOR_SHIFT; + + btrfs_bio_end_io(bbio, bbio->bio.bi_status); + btrfs_put_bioc(bioc); +} + +static void btrfs_orig_write_end_io(struct bio *bio) +{ + struct btrfs_bio *bbio = btrfs_bio(bio); + + INIT_WORK(&bbio->end_io_work, orig_write_end_io_work); + queue_work(btrfs_end_io_wq(bbio->inode->root->fs_info, bio), &bbio->end_io_work); +} + +static void clone_write_end_io_work(struct work_struct *work) +{ + struct btrfs_bio *bbio = container_of(work, struct btrfs_bio, end_io_work); + struct bio *bio = &bbio->bio; + struct btrfs_io_stripe *stripe = bio->bi_private; + + if (bio->bi_status) { + atomic_inc(&stripe->bioc->error); + btrfs_log_dev_io_error(bio, stripe->dev); + } else if (bio_is_zone_append(bio)) { + stripe->physical = bio->bi_iter.bi_sector << SECTOR_SHIFT; + } + + /* Pass on control to the original bio this one was cloned from */ + bio_endio(stripe->bioc->orig_bio); + bio_put(bio); +} + +static void btrfs_clone_write_end_io(struct bio *bio) +{ + struct btrfs_bio *bbio = btrfs_bio(bio); + + INIT_WORK(&bbio->end_io_work, clone_write_end_io_work); + queue_work(btrfs_end_io_wq(bbio->inode->root->fs_info, bio), &bbio->end_io_work); +} + +static void btrfs_submit_dev_bio(struct btrfs_device *dev, struct bio *bio) +{ + if (!dev || !dev->bdev || + test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state) || + (btrfs_op(bio) == BTRFS_MAP_WRITE && + !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state))) { + bio_io_error(bio); + return; + } + + bio_set_dev(bio, dev->bdev); + + /* + * For zone append writing, bi_sector must point the beginning of the + * zone + */ + if (bio_op(bio) == REQ_OP_ZONE_APPEND) { + u64 physical = bio->bi_iter.bi_sector << SECTOR_SHIFT; + u64 zone_start = round_down(physical, dev->fs_info->zone_size); + + ASSERT(btrfs_dev_is_sequential(dev, physical)); + bio->bi_iter.bi_sector = zone_start >> SECTOR_SHIFT; + } + btrfs_debug(dev->fs_info, + "%s: rw %d 0x%x, sector=%llu, dev=%lu (%s id %llu), size=%u", + __func__, bio_op(bio), bio->bi_opf, bio->bi_iter.bi_sector, + (unsigned long)dev->bdev->bd_dev, btrfs_dev_name(dev), + dev->devid, bio->bi_iter.bi_size); + + /* + * Track reads if tracking is enabled; ignore I/O operations before the + * filesystem is fully initialized. + */ + if (dev->fs_devices->collect_fs_stats && bio_op(bio) == REQ_OP_READ && dev->fs_info) + percpu_counter_add(&dev->fs_info->stats_read_blocks, + bio->bi_iter.bi_size >> dev->fs_info->sectorsize_bits); + + if (bio->bi_opf & REQ_BTRFS_CGROUP_PUNT) + blkcg_punt_bio_submit(bio); + else + submit_bio(bio); +} + +static void btrfs_submit_mirrored_bio(struct btrfs_io_context *bioc, int dev_nr) +{ + struct bio *orig_bio = bioc->orig_bio, *bio; + struct btrfs_bio *orig_bbio = btrfs_bio(orig_bio); + + ASSERT(bio_op(orig_bio) != REQ_OP_READ); + + /* Reuse the bio embedded into the btrfs_bio for the last mirror */ + if (dev_nr == bioc->num_stripes - 1) { + bio = orig_bio; + bio->bi_end_io = btrfs_orig_write_end_io; + } else { + /* We need to use endio_work to run end_io in task context. */ + bio = bio_alloc_clone(NULL, orig_bio, GFP_NOFS, &btrfs_bioset); + bio_inc_remaining(orig_bio); + btrfs_bio_init(btrfs_bio(bio), orig_bbio->inode, + orig_bbio->file_offset, NULL, NULL); + bio->bi_end_io = btrfs_clone_write_end_io; + } + + bio->bi_private = &bioc->stripes[dev_nr]; + bio->bi_iter.bi_sector = bioc->stripes[dev_nr].physical >> SECTOR_SHIFT; + bioc->stripes[dev_nr].bioc = bioc; + bioc->size = bio->bi_iter.bi_size; + btrfs_submit_dev_bio(bioc->stripes[dev_nr].dev, bio); +} + +static void btrfs_submit_bio(struct bio *bio, struct btrfs_io_context *bioc, + struct btrfs_io_stripe *smap, int mirror_num) +{ + if (!bioc) { + /* Single mirror read/write fast path. */ + btrfs_bio(bio)->mirror_num = mirror_num; + bio->bi_iter.bi_sector = smap->physical >> SECTOR_SHIFT; + if (bio_op(bio) != REQ_OP_READ) + btrfs_bio(bio)->orig_physical = smap->physical; + bio->bi_private = smap->dev; + bio->bi_end_io = btrfs_simple_end_io; + btrfs_submit_dev_bio(smap->dev, bio); + } else if (bioc->map_type & BTRFS_BLOCK_GROUP_RAID56_MASK) { + /* Parity RAID write or read recovery. */ + bio->bi_private = bioc; + bio->bi_end_io = btrfs_raid56_end_io; + if (bio_op(bio) == REQ_OP_READ) + raid56_parity_recover(bio, bioc, mirror_num); + else + raid56_parity_write(bio, bioc); + } else { + /* Write to multiple mirrors. */ + int total_devs = bioc->num_stripes; + + bioc->orig_bio = bio; + for (int dev_nr = 0; dev_nr < total_devs; dev_nr++) + btrfs_submit_mirrored_bio(bioc, dev_nr); + } +} + +static int btrfs_bio_csum(struct btrfs_bio *bbio) +{ + if (bbio->bio.bi_opf & REQ_META) + return btree_csum_one_bio(bbio); +#ifdef CONFIG_BTRFS_EXPERIMENTAL + return btrfs_csum_one_bio(bbio, true); +#else + return btrfs_csum_one_bio(bbio, false); +#endif +} + +/* + * Async submit bios are used to offload expensive checksumming onto the worker + * threads. + */ +struct async_submit_bio { + struct btrfs_bio *bbio; + struct btrfs_io_context *bioc; + struct btrfs_io_stripe smap; + int mirror_num; + struct btrfs_work work; +}; + +/* + * In order to insert checksums into the metadata in large chunks, we wait + * until bio submission time. All the pages in the bio are checksummed and + * sums are attached onto the ordered extent record. + * + * At IO completion time the csums attached on the ordered extent record are + * inserted into the btree. + */ +static void run_one_async_start(struct btrfs_work *work) +{ + struct async_submit_bio *async = + container_of(work, struct async_submit_bio, work); + int ret; + + ret = btrfs_bio_csum(async->bbio); + if (ret) + async->bbio->bio.bi_status = errno_to_blk_status(ret); +} + +/* + * In order to insert checksums into the metadata in large chunks, we wait + * until bio submission time. All the pages in the bio are checksummed and + * sums are attached onto the ordered extent record. + * + * At IO completion time the csums attached on the ordered extent record are + * inserted into the tree. + * + * If called with @do_free == true, then it will free the work struct. + */ +static void run_one_async_done(struct btrfs_work *work, bool do_free) +{ + struct async_submit_bio *async = + container_of(work, struct async_submit_bio, work); + struct bio *bio = &async->bbio->bio; + + if (do_free) { + kfree(container_of(work, struct async_submit_bio, work)); + return; + } + + /* If an error occurred we just want to clean up the bio and move on. */ + if (bio->bi_status) { + btrfs_bio_end_io(async->bbio, bio->bi_status); + return; + } + + /* + * All of the bios that pass through here are from async helpers. + * Use REQ_BTRFS_CGROUP_PUNT to issue them from the owning cgroup's + * context. This changes nothing when cgroups aren't in use. + */ + bio->bi_opf |= REQ_BTRFS_CGROUP_PUNT; + btrfs_submit_bio(bio, async->bioc, &async->smap, async->mirror_num); +} + +static bool should_async_write(struct btrfs_bio *bbio) +{ + struct btrfs_fs_info *fs_info = bbio->inode->root->fs_info; + bool auto_csum_mode = true; + +#ifdef CONFIG_BTRFS_EXPERIMENTAL + struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; + enum btrfs_offload_csum_mode csum_mode = READ_ONCE(fs_devices->offload_csum_mode); + + if (csum_mode == BTRFS_OFFLOAD_CSUM_FORCE_ON) + return true; + /* + * Write bios will calculate checksum and submit bio at the same time. + * Unless explicitly required don't offload serial csum calculate and bio + * submit into a workqueue. + */ + return false; +#endif + + /* Submit synchronously if the checksum implementation is fast. */ + if (auto_csum_mode && test_bit(BTRFS_FS_CSUM_IMPL_FAST, &fs_info->flags)) + return false; + + /* + * Try to defer the submission to a workqueue to parallelize the + * checksum calculation unless the I/O is issued synchronously. + */ + if (op_is_sync(bbio->bio.bi_opf)) + return false; + + /* Zoned devices require I/O to be submitted in order. */ + if ((bbio->bio.bi_opf & REQ_META) && btrfs_is_zoned(fs_info)) + return false; + + return true; +} + +/* + * Submit bio to an async queue. + * + * Return true if the work has been successfully submitted, else false. + */ +static bool btrfs_wq_submit_bio(struct btrfs_bio *bbio, + struct btrfs_io_context *bioc, + struct btrfs_io_stripe *smap, int mirror_num) +{ + struct btrfs_fs_info *fs_info = bbio->inode->root->fs_info; + struct async_submit_bio *async; + + async = kmalloc(sizeof(*async), GFP_NOFS); + if (!async) + return false; + + async->bbio = bbio; + async->bioc = bioc; + async->smap = *smap; + async->mirror_num = mirror_num; + + btrfs_init_work(&async->work, run_one_async_start, run_one_async_done); + btrfs_queue_work(fs_info->workers, &async->work); + return true; +} + +static u64 btrfs_append_map_length(struct btrfs_bio *bbio, u64 map_length) +{ + struct btrfs_fs_info *fs_info = bbio->inode->root->fs_info; + unsigned int nr_segs; + int sector_offset; + + map_length = min(map_length, fs_info->max_zone_append_size); + sector_offset = bio_split_rw_at(&bbio->bio, &fs_info->limits, + &nr_segs, map_length); + if (sector_offset) { + /* + * bio_split_rw_at() could split at a size smaller than our + * sectorsize and thus cause unaligned I/Os. Fix that by + * always rounding down to the nearest boundary. + */ + return ALIGN_DOWN(sector_offset << SECTOR_SHIFT, fs_info->sectorsize); + } + return map_length; +} + +static bool btrfs_submit_chunk(struct btrfs_bio *bbio, int mirror_num) +{ + struct btrfs_inode *inode = bbio->inode; + struct btrfs_fs_info *fs_info = inode->root->fs_info; + struct bio *bio = &bbio->bio; + u64 logical = bio->bi_iter.bi_sector << SECTOR_SHIFT; + u64 length = bio->bi_iter.bi_size; + u64 map_length = length; + bool use_append = btrfs_use_zone_append(bbio); + struct btrfs_io_context *bioc = NULL; + struct btrfs_io_stripe smap; + blk_status_t status; + int ret; + + if (bbio->is_scrub || btrfs_is_data_reloc_root(inode->root)) + smap.rst_search_commit_root = true; + else + smap.rst_search_commit_root = false; + + btrfs_bio_counter_inc_blocked(fs_info); + ret = btrfs_map_block(fs_info, btrfs_op(bio), logical, &map_length, + &bioc, &smap, &mirror_num); + if (ret) { + status = errno_to_blk_status(ret); + btrfs_bio_counter_dec(fs_info); + goto end_bbio; + } + + /* + * For fscrypt writes we will get the encrypted bio after we've remapped + * our bio to the physical disk location, so we need to save the + * original bytenr so we know what we're checksumming. + */ + if (bio_op(bio) == REQ_OP_WRITE && is_data_bbio(bbio)) + bbio->orig_logical = logical; + + map_length = min(map_length, length); + if (use_append) + map_length = btrfs_append_map_length(bbio, map_length); + + if (map_length < length) { + struct btrfs_bio *split; + + split = btrfs_split_bio(fs_info, bbio, map_length); + if (IS_ERR(split)) { + status = errno_to_blk_status(PTR_ERR(split)); + btrfs_bio_counter_dec(fs_info); + goto end_bbio; + } + bbio = split; + bio = &bbio->bio; + } + + /* + * Save the iter for the end_io handler and preload the checksums for + * data reads. + */ + if (bio_op(bio) == REQ_OP_READ && is_data_bbio(bbio)) { + bbio->saved_iter = bio->bi_iter; + ret = btrfs_lookup_bio_sums(bbio); + status = errno_to_blk_status(ret); + if (status) + goto fail; + } + + if (btrfs_op(bio) == BTRFS_MAP_WRITE) { + if (use_append) { + bio->bi_opf &= ~REQ_OP_WRITE; + bio->bi_opf |= REQ_OP_ZONE_APPEND; + } + + if (is_data_bbio(bbio) && bioc && bioc->use_rst) { + /* + * No locking for the list update, as we only add to + * the list in the I/O submission path, and list + * iteration only happens in the completion path, which + * can't happen until after the last submission. + */ + btrfs_get_bioc(bioc); + list_add_tail(&bioc->rst_ordered_entry, &bbio->ordered->bioc_list); + } + + /* + * Csum items for reloc roots have already been cloned at this + * point, so they are handled as part of the no-checksum case. + */ + if (!(inode->flags & BTRFS_INODE_NODATASUM) && + !test_bit(BTRFS_FS_STATE_NO_DATA_CSUMS, &fs_info->fs_state) && + !btrfs_is_data_reloc_root(inode->root)) { + if (should_async_write(bbio) && + btrfs_wq_submit_bio(bbio, bioc, &smap, mirror_num)) + goto done; + + ret = btrfs_bio_csum(bbio); + status = errno_to_blk_status(ret); + if (status) + goto fail; + } else if (use_append || + (btrfs_is_zoned(fs_info) && inode && + inode->flags & BTRFS_INODE_NODATASUM)) { + ret = btrfs_alloc_dummy_sum(bbio); + status = errno_to_blk_status(ret); + if (status) + goto fail; + } + } + + btrfs_submit_bio(bio, bioc, &smap, mirror_num); +done: + return map_length == length; + +fail: + btrfs_bio_counter_dec(fs_info); + /* + * We have split the original bbio, now we have to end both the current + * @bbio and remaining one, as the remaining one will never be submitted. + */ + if (map_length < length) { + struct btrfs_bio *remaining = bbio->private; + + ASSERT(bbio->bio.bi_pool == &btrfs_clone_bioset); + ASSERT(remaining); + + btrfs_bio_end_io(remaining, status); + } +end_bbio: + btrfs_bio_end_io(bbio, status); + /* Do not submit another chunk */ + return true; +} + +static void assert_bbio_alignment(struct btrfs_bio *bbio) +{ +#ifdef CONFIG_BTRFS_ASSERT + struct btrfs_fs_info *fs_info = bbio->inode->root->fs_info; + struct bio_vec bvec; + struct bvec_iter iter; + const u32 blocksize = fs_info->sectorsize; + const u32 alignment = min(blocksize, PAGE_SIZE); + const u64 logical = bbio->bio.bi_iter.bi_sector << SECTOR_SHIFT; + const u32 length = bbio->bio.bi_iter.bi_size; + + /* The logical and length should still be aligned to blocksize. */ + ASSERT(IS_ALIGNED(logical, blocksize) && IS_ALIGNED(length, blocksize) && + length != 0, "root=%llu inode=%llu logical=%llu length=%u", + btrfs_root_id(bbio->inode->root), + btrfs_ino(bbio->inode), logical, length); + + bio_for_each_bvec(bvec, &bbio->bio, iter) + ASSERT(IS_ALIGNED(bvec.bv_offset, alignment) && + IS_ALIGNED(bvec.bv_len, alignment), + "root=%llu inode=%llu logical=%llu length=%u index=%u bv_offset=%u bv_len=%u", + btrfs_root_id(bbio->inode->root), + btrfs_ino(bbio->inode), logical, length, iter.bi_idx, + bvec.bv_offset, bvec.bv_len); +#endif +} + +void btrfs_submit_bbio(struct btrfs_bio *bbio, int mirror_num) +{ + /* If bbio->inode is not populated, its file_offset must be 0. */ + ASSERT(bbio->inode || bbio->file_offset == 0); + + assert_bbio_alignment(bbio); + + while (!btrfs_submit_chunk(bbio, mirror_num)) + ; +} + +/* + * Submit a repair write. + * + * This bypasses btrfs_submit_bbio() deliberately, as that writes all copies in a + * RAID setup. Here we only want to write the one bad copy, so we do the + * mapping ourselves and submit the bio directly. + * + * The I/O is issued synchronously to block the repair read completion from + * freeing the bio. + * + * @ino: Offending inode number + * @fileoff: File offset inside the inode + * @length: Length of the repair write + * @logical: Logical address of the range + * @paddrs: Physical address array of the content + * @step: Length of for each paddrs + * @mirror_num: Mirror number to write to. Must not be zero + */ +int btrfs_repair_io_failure(struct btrfs_fs_info *fs_info, u64 ino, u64 fileoff, + u32 length, u64 logical, const phys_addr_t paddrs[], + unsigned int step, int mirror_num) +{ + const u32 nr_steps = DIV_ROUND_UP_POW2(length, step); + struct btrfs_io_stripe smap = { 0 }; + struct bio *bio = NULL; + int ret = 0; + + ASSERT(!(fs_info->sb->s_flags & SB_RDONLY)); + BUG_ON(!mirror_num); + + /* Basic alignment checks. */ + ASSERT(IS_ALIGNED(logical, fs_info->sectorsize)); + ASSERT(IS_ALIGNED(length, fs_info->sectorsize)); + ASSERT(IS_ALIGNED(fileoff, fs_info->sectorsize)); + /* Either it's a single data or metadata block. */ + ASSERT(length <= BTRFS_MAX_BLOCKSIZE); + ASSERT(step <= length); + ASSERT(is_power_of_2(step)); + + if (btrfs_repair_one_zone(fs_info, logical)) + return 0; + + /* + * Avoid races with device replace and make sure our bioc has devices + * associated to its stripes that don't go away while we are doing the + * read repair operation. + */ + btrfs_bio_counter_inc_blocked(fs_info); + ret = btrfs_map_repair_block(fs_info, &smap, logical, length, mirror_num); + if (ret < 0) + goto out_counter_dec; + + if (unlikely(!smap.dev->bdev || + !test_bit(BTRFS_DEV_STATE_WRITEABLE, &smap.dev->dev_state))) { + ret = -EIO; + goto out_counter_dec; + } + + bio = bio_alloc(smap.dev->bdev, nr_steps, REQ_OP_WRITE | REQ_SYNC, GFP_NOFS); + bio->bi_iter.bi_sector = smap.physical >> SECTOR_SHIFT; + for (int i = 0; i < nr_steps; i++) { + ret = bio_add_page(bio, phys_to_page(paddrs[i]), step, offset_in_page(paddrs[i])); + /* We should have allocated enough slots to contain all the different pages. */ + ASSERT(ret == step); + } + ret = submit_bio_wait(bio); + bio_put(bio); + if (ret) { + /* try to remap that extent elsewhere? */ + btrfs_dev_stat_inc_and_print(smap.dev, BTRFS_DEV_STAT_WRITE_ERRS); + goto out_counter_dec; + } + + btrfs_info_rl(fs_info, + "read error corrected: ino %llu off %llu (dev %s sector %llu)", + ino, fileoff, btrfs_dev_name(smap.dev), + smap.physical >> SECTOR_SHIFT); + ret = 0; + +out_counter_dec: + btrfs_bio_counter_dec(fs_info); + return ret; +} + +/* + * Submit a btrfs_bio based repair write. + * + * If @dev_replace is true, the write would be submitted to dev-replace target. + */ +void btrfs_submit_repair_write(struct btrfs_bio *bbio, int mirror_num, bool dev_replace) +{ + struct btrfs_fs_info *fs_info = bbio->inode->root->fs_info; + u64 logical = bbio->bio.bi_iter.bi_sector << SECTOR_SHIFT; + u64 length = bbio->bio.bi_iter.bi_size; + struct btrfs_io_stripe smap = { 0 }; + int ret; + + ASSERT(mirror_num > 0); + ASSERT(btrfs_op(&bbio->bio) == BTRFS_MAP_WRITE); + ASSERT(!is_data_inode(bbio->inode)); + ASSERT(bbio->is_scrub); + + btrfs_bio_counter_inc_blocked(fs_info); + ret = btrfs_map_repair_block(fs_info, &smap, logical, length, mirror_num); + if (ret < 0) + goto fail; + + if (dev_replace) { + ASSERT(smap.dev == fs_info->dev_replace.srcdev); + smap.dev = fs_info->dev_replace.tgtdev; + } + btrfs_submit_bio(&bbio->bio, NULL, &smap, mirror_num); + return; + +fail: + btrfs_bio_counter_dec(fs_info); + btrfs_bio_end_io(bbio, errno_to_blk_status(ret)); +} + +int __init btrfs_bioset_init(void) +{ + if (bioset_init(&btrfs_bioset, BIO_POOL_SIZE, + offsetof(struct btrfs_bio, bio), + BIOSET_NEED_BVECS)) + return -ENOMEM; + if (bioset_init(&btrfs_clone_bioset, BIO_POOL_SIZE, + offsetof(struct btrfs_bio, bio), 0)) + goto out; + if (bioset_init(&btrfs_repair_bioset, BIO_POOL_SIZE, + offsetof(struct btrfs_bio, bio), + BIOSET_NEED_BVECS)) + goto out; + if (mempool_init_kmalloc_pool(&btrfs_failed_bio_pool, BIO_POOL_SIZE, + sizeof(struct btrfs_failed_bio))) + goto out; + return 0; + +out: + btrfs_bioset_exit(); + return -ENOMEM; +} + +void __cold btrfs_bioset_exit(void) +{ + mempool_exit(&btrfs_failed_bio_pool); + bioset_exit(&btrfs_repair_bioset); + bioset_exit(&btrfs_clone_bioset); + bioset_exit(&btrfs_bioset); +} |