+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0
-#ifndef NO_BCACHEFS_FS
-
-#include "bcachefs.h"
-#include "alloc_foreground.h"
-#include "fs.h"
-#include "fs-io.h"
-#include "fs-io-direct.h"
-#include "fs-io-pagecache.h"
-#include "io_read.h"
-#include "io_write.h"
-
-#include <linux/kthread.h>
-#include <linux/pagemap.h>
-#include <linux/prefetch.h>
-#include <linux/task_io_accounting_ops.h>
-
-/* O_DIRECT reads */
-
-struct dio_read {
- struct closure cl;
- struct kiocb *req;
- long ret;
- bool should_dirty;
- struct bch_read_bio rbio;
-};
-
-static void bio_check_or_release(struct bio *bio, bool check_dirty)
-{
- if (check_dirty) {
- bio_check_pages_dirty(bio);
- } else {
- bio_release_pages(bio, false);
- bio_put(bio);
- }
-}
-
-static CLOSURE_CALLBACK(bch2_dio_read_complete)
-{
- closure_type(dio, struct dio_read, cl);
-
- dio->req->ki_complete(dio->req, dio->ret);
- bio_check_or_release(&dio->rbio.bio, dio->should_dirty);
-}
-
-static void bch2_direct_IO_read_endio(struct bio *bio)
-{
- struct dio_read *dio = bio->bi_private;
-
- if (bio->bi_status)
- dio->ret = blk_status_to_errno(bio->bi_status);
-
- closure_put(&dio->cl);
-}
-
-static void bch2_direct_IO_read_split_endio(struct bio *bio)
-{
- struct dio_read *dio = bio->bi_private;
- bool should_dirty = dio->should_dirty;
-
- bch2_direct_IO_read_endio(bio);
- bio_check_or_release(bio, should_dirty);
-}
-
-static int bch2_direct_IO_read(struct kiocb *req, struct iov_iter *iter)
-{
- struct file *file = req->ki_filp;
- struct bch_inode_info *inode = file_bch_inode(file);
- struct bch_fs *c = inode->v.i_sb->s_fs_info;
- struct bch_io_opts opts;
- struct dio_read *dio;
- struct bio *bio;
- loff_t offset = req->ki_pos;
- bool sync = is_sync_kiocb(req);
- size_t shorten;
- ssize_t ret;
-
- bch2_inode_opts_get(&opts, c, &inode->ei_inode);
-
- ret = min_t(loff_t, iter->count,
- max_t(loff_t, 0, i_size_read(&inode->v) - offset));
-
- if (!ret)
- return ret;
-
- shorten = iov_iter_count(iter) - round_up(ret, block_bytes(c));
- iter->count -= shorten;
-
- bio = bio_alloc_bioset(NULL,
- bio_iov_vecs_to_alloc(iter, BIO_MAX_VECS),
- REQ_OP_READ,
- GFP_KERNEL,
- &c->dio_read_bioset);
-
- bio->bi_end_io = bch2_direct_IO_read_endio;
-
- dio = container_of(bio, struct dio_read, rbio.bio);
- closure_init(&dio->cl, NULL);
-
- /*
- * this is a _really_ horrible hack just to avoid an atomic sub at the
- * end:
- */
- if (!sync) {
- set_closure_fn(&dio->cl, bch2_dio_read_complete, NULL);
- atomic_set(&dio->cl.remaining,
- CLOSURE_REMAINING_INITIALIZER -
- CLOSURE_RUNNING +
- CLOSURE_DESTRUCTOR);
- } else {
- atomic_set(&dio->cl.remaining,
- CLOSURE_REMAINING_INITIALIZER + 1);
- dio->cl.closure_get_happened = true;
- }
-
- dio->req = req;
- dio->ret = ret;
- /*
- * This is one of the sketchier things I've encountered: we have to skip
- * the dirtying of requests that are internal from the kernel (i.e. from
- * loopback), because we'll deadlock on page_lock.
- */
- dio->should_dirty = iter_is_iovec(iter);
-
- goto start;
- while (iter->count) {
- bio = bio_alloc_bioset(NULL,
- bio_iov_vecs_to_alloc(iter, BIO_MAX_VECS),
- REQ_OP_READ,
- GFP_KERNEL,
- &c->bio_read);
- bio->bi_end_io = bch2_direct_IO_read_split_endio;
-start:
- bio->bi_opf = REQ_OP_READ|REQ_SYNC;
- bio->bi_iter.bi_sector = offset >> 9;
- bio->bi_private = dio;
-
- ret = bio_iov_iter_get_pages(bio, iter);
- if (ret < 0) {
- /* XXX: fault inject this path */
- bio->bi_status = BLK_STS_RESOURCE;
- bio_endio(bio);
- break;
- }
-
- offset += bio->bi_iter.bi_size;
-
- if (dio->should_dirty)
- bio_set_pages_dirty(bio);
-
- if (iter->count)
- closure_get(&dio->cl);
-
- bch2_read(c, rbio_init(bio, opts), inode_inum(inode));
- }
-
- iter->count += shorten;
-
- if (sync) {
- closure_sync(&dio->cl);
- closure_debug_destroy(&dio->cl);
- ret = dio->ret;
- bio_check_or_release(&dio->rbio.bio, dio->should_dirty);
- return ret;
- } else {
- return -EIOCBQUEUED;
- }
-}
-
-ssize_t bch2_read_iter(struct kiocb *iocb, struct iov_iter *iter)
-{
- struct file *file = iocb->ki_filp;
- struct bch_inode_info *inode = file_bch_inode(file);
- struct address_space *mapping = file->f_mapping;
- size_t count = iov_iter_count(iter);
- ssize_t ret;
-
- if (!count)
- return 0; /* skip atime */
-
- if (iocb->ki_flags & IOCB_DIRECT) {
- struct blk_plug plug;
-
- if (unlikely(mapping->nrpages)) {
- ret = filemap_write_and_wait_range(mapping,
- iocb->ki_pos,
- iocb->ki_pos + count - 1);
- if (ret < 0)
- goto out;
- }
-
- file_accessed(file);
-
- blk_start_plug(&plug);
- ret = bch2_direct_IO_read(iocb, iter);
- blk_finish_plug(&plug);
-
- if (ret >= 0)
- iocb->ki_pos += ret;
- } else {
- bch2_pagecache_add_get(inode);
- ret = generic_file_read_iter(iocb, iter);
- bch2_pagecache_add_put(inode);
- }
-out:
- return bch2_err_class(ret);
-}
-
-/* O_DIRECT writes */
-
-struct dio_write {
- struct kiocb *req;
- struct address_space *mapping;
- struct bch_inode_info *inode;
- struct mm_struct *mm;
- const struct iovec *iov;
- unsigned loop:1,
- extending:1,
- sync:1,
- flush:1;
- struct quota_res quota_res;
- u64 written;
-
- struct iov_iter iter;
- struct iovec inline_vecs[2];
-
- /* must be last: */
- struct bch_write_op op;
-};
-
-static bool bch2_check_range_allocated(struct bch_fs *c, subvol_inum inum,
- u64 offset, u64 size,
- unsigned nr_replicas, bool compressed)
-{
- struct btree_trans *trans = bch2_trans_get(c);
- struct btree_iter iter;
- struct bkey_s_c k;
- u64 end = offset + size;
- u32 snapshot;
- bool ret = true;
- int err;
-retry:
- bch2_trans_begin(trans);
-
- err = bch2_subvolume_get_snapshot(trans, inum.subvol, &snapshot);
- if (err)
- goto err;
-
- for_each_btree_key_norestart(trans, iter, BTREE_ID_extents,
- SPOS(inum.inum, offset, snapshot),
- BTREE_ITER_SLOTS, k, err) {
- if (bkey_ge(bkey_start_pos(k.k), POS(inum.inum, end)))
- break;
-
- if (k.k->p.snapshot != snapshot ||
- nr_replicas > bch2_bkey_replicas(c, k) ||
- (!compressed && bch2_bkey_sectors_compressed(k))) {
- ret = false;
- break;
- }
- }
-
- offset = iter.pos.offset;
- bch2_trans_iter_exit(trans, &iter);
-err:
- if (bch2_err_matches(err, BCH_ERR_transaction_restart))
- goto retry;
- bch2_trans_put(trans);
-
- return err ? false : ret;
-}
-
-static noinline bool bch2_dio_write_check_allocated(struct dio_write *dio)
-{
- struct bch_fs *c = dio->op.c;
- struct bch_inode_info *inode = dio->inode;
- struct bio *bio = &dio->op.wbio.bio;
-
- return bch2_check_range_allocated(c, inode_inum(inode),
- dio->op.pos.offset, bio_sectors(bio),
- dio->op.opts.data_replicas,
- dio->op.opts.compression != 0);
-}
-
-static void bch2_dio_write_loop_async(struct bch_write_op *);
-static __always_inline long bch2_dio_write_done(struct dio_write *dio);
-
-/*
- * We're going to return -EIOCBQUEUED, but we haven't finished consuming the
- * iov_iter yet, so we need to stash a copy of the iovec: it might be on the
- * caller's stack, we're not guaranteed that it will live for the duration of
- * the IO:
- */
-static noinline int bch2_dio_write_copy_iov(struct dio_write *dio)
-{
- struct iovec *iov = dio->inline_vecs;
-
- /*
- * iov_iter has a single embedded iovec - nothing to do:
- */
- if (iter_is_ubuf(&dio->iter))
- return 0;
-
- /*
- * We don't currently handle non-iovec iov_iters here - return an error,
- * and we'll fall back to doing the IO synchronously:
- */
- if (!iter_is_iovec(&dio->iter))
- return -1;
-
- if (dio->iter.nr_segs > ARRAY_SIZE(dio->inline_vecs)) {
- dio->iov = iov = kmalloc_array(dio->iter.nr_segs, sizeof(*iov),
- GFP_KERNEL);
- if (unlikely(!iov))
- return -ENOMEM;
- }
-
- memcpy(iov, dio->iter.__iov, dio->iter.nr_segs * sizeof(*iov));
- dio->iter.__iov = iov;
- return 0;
-}
-
-static CLOSURE_CALLBACK(bch2_dio_write_flush_done)
-{
- closure_type(dio, struct dio_write, op.cl);
- struct bch_fs *c = dio->op.c;
-
- closure_debug_destroy(cl);
-
- dio->op.error = bch2_journal_error(&c->journal);
-
- bch2_dio_write_done(dio);
-}
-
-static noinline void bch2_dio_write_flush(struct dio_write *dio)
-{
- struct bch_fs *c = dio->op.c;
- struct bch_inode_unpacked inode;
- int ret;
-
- dio->flush = 0;
-
- closure_init(&dio->op.cl, NULL);
-
- if (!dio->op.error) {
- ret = bch2_inode_find_by_inum(c, inode_inum(dio->inode), &inode);
- if (ret) {
- dio->op.error = ret;
- } else {
- bch2_journal_flush_seq_async(&c->journal, inode.bi_journal_seq,
- &dio->op.cl);
- bch2_inode_flush_nocow_writes_async(c, dio->inode, &dio->op.cl);
- }
- }
-
- if (dio->sync) {
- closure_sync(&dio->op.cl);
- closure_debug_destroy(&dio->op.cl);
- } else {
- continue_at(&dio->op.cl, bch2_dio_write_flush_done, NULL);
- }
-}
-
-static __always_inline long bch2_dio_write_done(struct dio_write *dio)
-{
- struct kiocb *req = dio->req;
- struct bch_inode_info *inode = dio->inode;
- bool sync = dio->sync;
- long ret;
-
- if (unlikely(dio->flush)) {
- bch2_dio_write_flush(dio);
- if (!sync)
- return -EIOCBQUEUED;
- }
-
- bch2_pagecache_block_put(inode);
-
- kfree(dio->iov);
-
- ret = dio->op.error ?: ((long) dio->written << 9);
- bio_put(&dio->op.wbio.bio);
-
- /* inode->i_dio_count is our ref on inode and thus bch_fs */
- inode_dio_end(&inode->v);
-
- if (ret < 0)
- ret = bch2_err_class(ret);
-
- if (!sync) {
- req->ki_complete(req, ret);
- ret = -EIOCBQUEUED;
- }
- return ret;
-}
-
-static __always_inline void bch2_dio_write_end(struct dio_write *dio)
-{
- struct bch_fs *c = dio->op.c;
- struct kiocb *req = dio->req;
- struct bch_inode_info *inode = dio->inode;
- struct bio *bio = &dio->op.wbio.bio;
-
- req->ki_pos += (u64) dio->op.written << 9;
- dio->written += dio->op.written;
-
- if (dio->extending) {
- spin_lock(&inode->v.i_lock);
- if (req->ki_pos > inode->v.i_size)
- i_size_write(&inode->v, req->ki_pos);
- spin_unlock(&inode->v.i_lock);
- }
-
- if (dio->op.i_sectors_delta || dio->quota_res.sectors) {
- mutex_lock(&inode->ei_quota_lock);
- __bch2_i_sectors_acct(c, inode, &dio->quota_res, dio->op.i_sectors_delta);
- __bch2_quota_reservation_put(c, inode, &dio->quota_res);
- mutex_unlock(&inode->ei_quota_lock);
- }
-
- bio_release_pages(bio, false);
-
- if (unlikely(dio->op.error))
- set_bit(EI_INODE_ERROR, &inode->ei_flags);
-}
-
-static __always_inline long bch2_dio_write_loop(struct dio_write *dio)
-{
- struct bch_fs *c = dio->op.c;
- struct kiocb *req = dio->req;
- struct address_space *mapping = dio->mapping;
- struct bch_inode_info *inode = dio->inode;
- struct bch_io_opts opts;
- struct bio *bio = &dio->op.wbio.bio;
- unsigned unaligned, iter_count;
- bool sync = dio->sync, dropped_locks;
- long ret;
-
- bch2_inode_opts_get(&opts, c, &inode->ei_inode);
-
- while (1) {
- iter_count = dio->iter.count;
-
- EBUG_ON(current->faults_disabled_mapping);
- current->faults_disabled_mapping = mapping;
-
- ret = bio_iov_iter_get_pages(bio, &dio->iter);
-
- dropped_locks = fdm_dropped_locks();
-
- current->faults_disabled_mapping = NULL;
-
- /*
- * If the fault handler returned an error but also signalled
- * that it dropped & retook ei_pagecache_lock, we just need to
- * re-shoot down the page cache and retry:
- */
- if (dropped_locks && ret)
- ret = 0;
-
- if (unlikely(ret < 0))
- goto err;
-
- if (unlikely(dropped_locks)) {
- ret = bch2_write_invalidate_inode_pages_range(mapping,
- req->ki_pos,
- req->ki_pos + iter_count - 1);
- if (unlikely(ret))
- goto err;
-
- if (!bio->bi_iter.bi_size)
- continue;
- }
-
- unaligned = bio->bi_iter.bi_size & (block_bytes(c) - 1);
- bio->bi_iter.bi_size -= unaligned;
- iov_iter_revert(&dio->iter, unaligned);
-
- if (!bio->bi_iter.bi_size) {
- /*
- * bio_iov_iter_get_pages was only able to get <
- * blocksize worth of pages:
- */
- ret = -EFAULT;
- goto err;
- }
-
- bch2_write_op_init(&dio->op, c, opts);
- dio->op.end_io = sync
- ? NULL
- : bch2_dio_write_loop_async;
- dio->op.target = dio->op.opts.foreground_target;
- dio->op.write_point = writepoint_hashed((unsigned long) current);
- dio->op.nr_replicas = dio->op.opts.data_replicas;
- dio->op.subvol = inode->ei_subvol;
- dio->op.pos = POS(inode->v.i_ino, (u64) req->ki_pos >> 9);
- dio->op.devs_need_flush = &inode->ei_devs_need_flush;
-
- if (sync)
- dio->op.flags |= BCH_WRITE_SYNC;
- dio->op.flags |= BCH_WRITE_CHECK_ENOSPC;
-
- ret = bch2_quota_reservation_add(c, inode, &dio->quota_res,
- bio_sectors(bio), true);
- if (unlikely(ret))
- goto err;
-
- ret = bch2_disk_reservation_get(c, &dio->op.res, bio_sectors(bio),
- dio->op.opts.data_replicas, 0);
- if (unlikely(ret) &&
- !bch2_dio_write_check_allocated(dio))
- goto err;
-
- task_io_account_write(bio->bi_iter.bi_size);
-
- if (unlikely(dio->iter.count) &&
- !dio->sync &&
- !dio->loop &&
- bch2_dio_write_copy_iov(dio))
- dio->sync = sync = true;
-
- dio->loop = true;
- closure_call(&dio->op.cl, bch2_write, NULL, NULL);
-
- if (!sync)
- return -EIOCBQUEUED;
-
- bch2_dio_write_end(dio);
-
- if (likely(!dio->iter.count) || dio->op.error)
- break;
-
- bio_reset(bio, NULL, REQ_OP_WRITE);
- }
-out:
- return bch2_dio_write_done(dio);
-err:
- dio->op.error = ret;
-
- bio_release_pages(bio, false);
-
- bch2_quota_reservation_put(c, inode, &dio->quota_res);
- goto out;
-}
-
-static noinline __cold void bch2_dio_write_continue(struct dio_write *dio)
-{
- struct mm_struct *mm = dio->mm;
-
- bio_reset(&dio->op.wbio.bio, NULL, REQ_OP_WRITE);
-
- if (mm)
- kthread_use_mm(mm);
- bch2_dio_write_loop(dio);
- if (mm)
- kthread_unuse_mm(mm);
-}
-
-static void bch2_dio_write_loop_async(struct bch_write_op *op)
-{
- struct dio_write *dio = container_of(op, struct dio_write, op);
-
- bch2_dio_write_end(dio);
-
- if (likely(!dio->iter.count) || dio->op.error)
- bch2_dio_write_done(dio);
- else
- bch2_dio_write_continue(dio);
-}
-
-ssize_t bch2_direct_write(struct kiocb *req, struct iov_iter *iter)
-{
- struct file *file = req->ki_filp;
- struct address_space *mapping = file->f_mapping;
- struct bch_inode_info *inode = file_bch_inode(file);
- struct bch_fs *c = inode->v.i_sb->s_fs_info;
- struct dio_write *dio;
- struct bio *bio;
- bool locked = true, extending;
- ssize_t ret;
-
- prefetch(&c->opts);
- prefetch((void *) &c->opts + 64);
- prefetch(&inode->ei_inode);
- prefetch((void *) &inode->ei_inode + 64);
-
- inode_lock(&inode->v);
-
- ret = generic_write_checks(req, iter);
- if (unlikely(ret <= 0))
- goto err;
-
- ret = file_remove_privs(file);
- if (unlikely(ret))
- goto err;
-
- ret = file_update_time(file);
- if (unlikely(ret))
- goto err;
-
- if (unlikely((req->ki_pos|iter->count) & (block_bytes(c) - 1)))
- goto err;
-
- inode_dio_begin(&inode->v);
- bch2_pagecache_block_get(inode);
-
- extending = req->ki_pos + iter->count > inode->v.i_size;
- if (!extending) {
- inode_unlock(&inode->v);
- locked = false;
- }
-
- bio = bio_alloc_bioset(NULL,
- bio_iov_vecs_to_alloc(iter, BIO_MAX_VECS),
- REQ_OP_WRITE,
- GFP_KERNEL,
- &c->dio_write_bioset);
- dio = container_of(bio, struct dio_write, op.wbio.bio);
- dio->req = req;
- dio->mapping = mapping;
- dio->inode = inode;
- dio->mm = current->mm;
- dio->iov = NULL;
- dio->loop = false;
- dio->extending = extending;
- dio->sync = is_sync_kiocb(req) || extending;
- dio->flush = iocb_is_dsync(req) && !c->opts.journal_flush_disabled;
- dio->quota_res.sectors = 0;
- dio->written = 0;
- dio->iter = *iter;
- dio->op.c = c;
-
- if (unlikely(mapping->nrpages)) {
- ret = bch2_write_invalidate_inode_pages_range(mapping,
- req->ki_pos,
- req->ki_pos + iter->count - 1);
- if (unlikely(ret))
- goto err_put_bio;
- }
-
- ret = bch2_dio_write_loop(dio);
-err:
- if (locked)
- inode_unlock(&inode->v);
- return ret;
-err_put_bio:
- bch2_pagecache_block_put(inode);
- bio_put(bio);
- inode_dio_end(&inode->v);
- goto err;
-}
-
-void bch2_fs_fs_io_direct_exit(struct bch_fs *c)
-{
- bioset_exit(&c->dio_write_bioset);
- bioset_exit(&c->dio_read_bioset);
-}
-
-int bch2_fs_fs_io_direct_init(struct bch_fs *c)
-{
- if (bioset_init(&c->dio_read_bioset,
- 4, offsetof(struct dio_read, rbio.bio),
- BIOSET_NEED_BVECS))
- return -BCH_ERR_ENOMEM_dio_read_bioset_init;
-
- if (bioset_init(&c->dio_write_bioset,
- 4, offsetof(struct dio_write, op.wbio.bio),
- BIOSET_NEED_BVECS))
- return -BCH_ERR_ENOMEM_dio_write_bioset_init;
-
- return 0;
-}
-
-#endif /* NO_BCACHEFS_FS */
projects / bcachefs-tools-debian / blobdiff