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1ddeeb2a05
-----BEGIN PGP SIGNATURE----- iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAmXuFO4QHGF4Ym9lQGtl cm5lbC5kawAKCRD301j7KXHgpq33D/9hyNyBce2A9iyo026eK8EqLDoed6BPzuvB kLKj5tsGvX4YlfuswvP86M5dgibTASXclnfUK394TijW/JPOfJ3mNhi9gMnHzRoK ZaR1di0Lum56dY1FkpMmWiGmE4fB79PAtXYKtajOkuoIcNzylncEAAACUY4/Ouhg Cm+LMg2prcc+m9g8rKDNQ51pUFg4U21KAUTl35XLMUAaQk1ahW3EDEVYhweC/zwE V/5hJsv8UY72+oQGY2Dc/YgQk/Zj4ZDh7C+oHR9XeB/ro99kr3/Vopagu0gBMLZi Rq6qqz6PVMhVcuz8uN2rsTQKXmXhsBn9/adsl4AKtdxcW5D5moWb5BLq1P0WQylc nzMxa1d6cVcTKZpaUQQv3Rj6ZMrLuDwP277UYHfn5x1oPWYRZCG7FtHuOo1gNcpG DrSNwVG6BSDcbABqI+MIS2oD1JoUMyevjwT7e2hOXukZhc6GLO5F3ODWE5j3KnCR S/aGSAmcdR4fTcgavULqWdQVt7SYl4f1IxT8KrUirJGVhc2LgahaWj69ooklVHoU fPDFRiruwJ5YkH4RWCSDm9mi4kAz6eUf+f4yE06wZOFOb2fT8/1ZK2Snpz2KeXuZ INO0RejtFzT8L0OUlu7dBmF20y6rgAYt87lR8mIt71yuuATIrVhzlX1VdsvhdrAo VLHGV1Ncgw== =WlVL -----END PGP SIGNATURE----- Merge tag 'for-6.9/block-20240310' of git://git.kernel.dk/linux Pull block updates from Jens Axboe: - MD pull requests via Song: - Cleanup redundant checks (Yu Kuai) - Remove deprecated headers (Marc Zyngier, Song Liu) - Concurrency fixes (Li Lingfeng) - Memory leak fix (Li Nan) - Refactor raid1 read_balance (Yu Kuai, Paul Luse) - Clean up and fix for md_ioctl (Li Nan) - Other small fixes (Gui-Dong Han, Heming Zhao) - MD atomic limits (Christoph) - NVMe pull request via Keith: - RDMA target enhancements (Max) - Fabrics fixes (Max, Guixin, Hannes) - Atomic queue_limits usage (Christoph) - Const use for class_register (Ricardo) - Identification error handling fixes (Shin'ichiro, Keith) - Improvement and cleanup for cached request handling (Christoph) - Moving towards atomic queue limits. Core changes and driver bits so far (Christoph) - Fix UAF issues in aoeblk (Chun-Yi) - Zoned fix and cleanups (Damien) - s390 dasd cleanups and fixes (Jan, Miroslav) - Block issue timestamp caching (me) - noio scope guarding for zoned IO (Johannes) - block/nvme PI improvements (Kanchan) - Ability to terminate long running discard loop (Keith) - bdev revalidation fix (Li) - Get rid of old nr_queues hack for kdump kernels (Ming) - Support for async deletion of ublk (Ming) - Improve IRQ bio recycling (Pavel) - Factor in CPU capacity for remote vs local completion (Qais) - Add shared_tags configfs entry for null_blk (Shin'ichiro - Fix for a regression in page refcounts introduced by the folio unification (Tony) - Misc fixes and cleanups (Arnd, Colin, John, Kunwu, Li, Navid, Ricardo, Roman, Tang, Uwe) * tag 'for-6.9/block-20240310' of git://git.kernel.dk/linux: (221 commits) block: partitions: only define function mac_fix_string for CONFIG_PPC_PMAC block/swim: Convert to platform remove callback returning void cdrom: gdrom: Convert to platform remove callback returning void block: remove disk_stack_limits md: remove mddev->queue md: don't initialize queue limits md/raid10: use the atomic queue limit update APIs md/raid5: use the atomic queue limit update APIs md/raid1: use the atomic queue limit update APIs md/raid0: use the atomic queue limit update APIs md: add queue limit helpers md: add a mddev_is_dm helper md: add a mddev_add_trace_msg helper md: add a mddev_trace_remap helper bcache: move calculation of stripe_size and io_opt into bcache_device_init virtio_blk: Do not use disk_set_max_open/active_zones() aoe: fix the potential use-after-free problem in aoecmd_cfg_pkts block: move capacity validation to blkpg_do_ioctl() block: prevent division by zero in blk_rq_stat_sum() drbd: atomically update queue limits in drbd_reconsider_queue_parameters ...
1808 lines
48 KiB
C
1808 lines
48 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Copyright (C) 2001 Jens Axboe <axboe@kernel.dk>
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*/
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#include <linux/mm.h>
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#include <linux/swap.h>
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#include <linux/bio.h>
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#include <linux/blkdev.h>
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#include <linux/uio.h>
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#include <linux/iocontext.h>
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#include <linux/slab.h>
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#include <linux/init.h>
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#include <linux/kernel.h>
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#include <linux/export.h>
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#include <linux/mempool.h>
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#include <linux/workqueue.h>
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#include <linux/cgroup.h>
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#include <linux/highmem.h>
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#include <linux/blk-crypto.h>
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#include <linux/xarray.h>
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#include <trace/events/block.h>
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#include "blk.h"
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#include "blk-rq-qos.h"
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#include "blk-cgroup.h"
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#define ALLOC_CACHE_THRESHOLD 16
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#define ALLOC_CACHE_MAX 256
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struct bio_alloc_cache {
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struct bio *free_list;
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struct bio *free_list_irq;
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unsigned int nr;
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unsigned int nr_irq;
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};
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static struct biovec_slab {
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int nr_vecs;
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char *name;
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struct kmem_cache *slab;
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} bvec_slabs[] __read_mostly = {
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{ .nr_vecs = 16, .name = "biovec-16" },
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{ .nr_vecs = 64, .name = "biovec-64" },
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{ .nr_vecs = 128, .name = "biovec-128" },
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{ .nr_vecs = BIO_MAX_VECS, .name = "biovec-max" },
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};
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static struct biovec_slab *biovec_slab(unsigned short nr_vecs)
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{
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switch (nr_vecs) {
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/* smaller bios use inline vecs */
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case 5 ... 16:
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return &bvec_slabs[0];
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case 17 ... 64:
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return &bvec_slabs[1];
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case 65 ... 128:
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return &bvec_slabs[2];
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case 129 ... BIO_MAX_VECS:
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return &bvec_slabs[3];
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default:
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BUG();
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return NULL;
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}
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}
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/*
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* fs_bio_set is the bio_set containing bio and iovec memory pools used by
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* IO code that does not need private memory pools.
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*/
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struct bio_set fs_bio_set;
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EXPORT_SYMBOL(fs_bio_set);
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/*
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* Our slab pool management
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*/
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struct bio_slab {
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struct kmem_cache *slab;
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unsigned int slab_ref;
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unsigned int slab_size;
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char name[8];
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};
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static DEFINE_MUTEX(bio_slab_lock);
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static DEFINE_XARRAY(bio_slabs);
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static struct bio_slab *create_bio_slab(unsigned int size)
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{
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struct bio_slab *bslab = kzalloc(sizeof(*bslab), GFP_KERNEL);
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if (!bslab)
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return NULL;
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snprintf(bslab->name, sizeof(bslab->name), "bio-%d", size);
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bslab->slab = kmem_cache_create(bslab->name, size,
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ARCH_KMALLOC_MINALIGN,
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SLAB_HWCACHE_ALIGN | SLAB_TYPESAFE_BY_RCU, NULL);
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if (!bslab->slab)
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goto fail_alloc_slab;
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bslab->slab_ref = 1;
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bslab->slab_size = size;
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if (!xa_err(xa_store(&bio_slabs, size, bslab, GFP_KERNEL)))
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return bslab;
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kmem_cache_destroy(bslab->slab);
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fail_alloc_slab:
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kfree(bslab);
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return NULL;
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}
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static inline unsigned int bs_bio_slab_size(struct bio_set *bs)
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{
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return bs->front_pad + sizeof(struct bio) + bs->back_pad;
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}
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static struct kmem_cache *bio_find_or_create_slab(struct bio_set *bs)
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{
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unsigned int size = bs_bio_slab_size(bs);
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struct bio_slab *bslab;
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mutex_lock(&bio_slab_lock);
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bslab = xa_load(&bio_slabs, size);
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if (bslab)
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bslab->slab_ref++;
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else
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bslab = create_bio_slab(size);
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mutex_unlock(&bio_slab_lock);
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if (bslab)
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return bslab->slab;
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return NULL;
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}
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static void bio_put_slab(struct bio_set *bs)
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{
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struct bio_slab *bslab = NULL;
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unsigned int slab_size = bs_bio_slab_size(bs);
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mutex_lock(&bio_slab_lock);
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bslab = xa_load(&bio_slabs, slab_size);
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if (WARN(!bslab, KERN_ERR "bio: unable to find slab!\n"))
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goto out;
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WARN_ON_ONCE(bslab->slab != bs->bio_slab);
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WARN_ON(!bslab->slab_ref);
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if (--bslab->slab_ref)
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goto out;
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xa_erase(&bio_slabs, slab_size);
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kmem_cache_destroy(bslab->slab);
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kfree(bslab);
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out:
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mutex_unlock(&bio_slab_lock);
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}
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void bvec_free(mempool_t *pool, struct bio_vec *bv, unsigned short nr_vecs)
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{
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BUG_ON(nr_vecs > BIO_MAX_VECS);
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if (nr_vecs == BIO_MAX_VECS)
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mempool_free(bv, pool);
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else if (nr_vecs > BIO_INLINE_VECS)
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kmem_cache_free(biovec_slab(nr_vecs)->slab, bv);
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}
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/*
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* Make the first allocation restricted and don't dump info on allocation
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* failures, since we'll fall back to the mempool in case of failure.
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*/
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static inline gfp_t bvec_alloc_gfp(gfp_t gfp)
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{
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return (gfp & ~(__GFP_DIRECT_RECLAIM | __GFP_IO)) |
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__GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN;
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}
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struct bio_vec *bvec_alloc(mempool_t *pool, unsigned short *nr_vecs,
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gfp_t gfp_mask)
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{
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struct biovec_slab *bvs = biovec_slab(*nr_vecs);
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if (WARN_ON_ONCE(!bvs))
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return NULL;
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/*
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* Upgrade the nr_vecs request to take full advantage of the allocation.
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* We also rely on this in the bvec_free path.
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*/
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*nr_vecs = bvs->nr_vecs;
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/*
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* Try a slab allocation first for all smaller allocations. If that
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* fails and __GFP_DIRECT_RECLAIM is set retry with the mempool.
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* The mempool is sized to handle up to BIO_MAX_VECS entries.
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*/
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if (*nr_vecs < BIO_MAX_VECS) {
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struct bio_vec *bvl;
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bvl = kmem_cache_alloc(bvs->slab, bvec_alloc_gfp(gfp_mask));
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if (likely(bvl) || !(gfp_mask & __GFP_DIRECT_RECLAIM))
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return bvl;
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*nr_vecs = BIO_MAX_VECS;
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}
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return mempool_alloc(pool, gfp_mask);
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}
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void bio_uninit(struct bio *bio)
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{
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#ifdef CONFIG_BLK_CGROUP
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if (bio->bi_blkg) {
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blkg_put(bio->bi_blkg);
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bio->bi_blkg = NULL;
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}
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#endif
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if (bio_integrity(bio))
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bio_integrity_free(bio);
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bio_crypt_free_ctx(bio);
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}
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EXPORT_SYMBOL(bio_uninit);
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static void bio_free(struct bio *bio)
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{
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struct bio_set *bs = bio->bi_pool;
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void *p = bio;
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WARN_ON_ONCE(!bs);
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bio_uninit(bio);
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bvec_free(&bs->bvec_pool, bio->bi_io_vec, bio->bi_max_vecs);
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mempool_free(p - bs->front_pad, &bs->bio_pool);
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}
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/*
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* Users of this function have their own bio allocation. Subsequently,
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* they must remember to pair any call to bio_init() with bio_uninit()
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* when IO has completed, or when the bio is released.
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*/
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void bio_init(struct bio *bio, struct block_device *bdev, struct bio_vec *table,
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unsigned short max_vecs, blk_opf_t opf)
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{
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bio->bi_next = NULL;
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bio->bi_bdev = bdev;
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bio->bi_opf = opf;
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bio->bi_flags = 0;
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bio->bi_ioprio = 0;
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bio->bi_write_hint = 0;
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bio->bi_status = 0;
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bio->bi_iter.bi_sector = 0;
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bio->bi_iter.bi_size = 0;
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bio->bi_iter.bi_idx = 0;
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bio->bi_iter.bi_bvec_done = 0;
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bio->bi_end_io = NULL;
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bio->bi_private = NULL;
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#ifdef CONFIG_BLK_CGROUP
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bio->bi_blkg = NULL;
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bio->bi_issue.value = 0;
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if (bdev)
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bio_associate_blkg(bio);
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#ifdef CONFIG_BLK_CGROUP_IOCOST
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bio->bi_iocost_cost = 0;
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#endif
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#endif
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#ifdef CONFIG_BLK_INLINE_ENCRYPTION
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bio->bi_crypt_context = NULL;
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#endif
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#ifdef CONFIG_BLK_DEV_INTEGRITY
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bio->bi_integrity = NULL;
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#endif
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bio->bi_vcnt = 0;
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atomic_set(&bio->__bi_remaining, 1);
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atomic_set(&bio->__bi_cnt, 1);
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bio->bi_cookie = BLK_QC_T_NONE;
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bio->bi_max_vecs = max_vecs;
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bio->bi_io_vec = table;
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bio->bi_pool = NULL;
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}
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EXPORT_SYMBOL(bio_init);
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/**
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* bio_reset - reinitialize a bio
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* @bio: bio to reset
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* @bdev: block device to use the bio for
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* @opf: operation and flags for bio
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*
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* Description:
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* After calling bio_reset(), @bio will be in the same state as a freshly
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* allocated bio returned bio bio_alloc_bioset() - the only fields that are
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* preserved are the ones that are initialized by bio_alloc_bioset(). See
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* comment in struct bio.
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*/
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void bio_reset(struct bio *bio, struct block_device *bdev, blk_opf_t opf)
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{
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bio_uninit(bio);
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memset(bio, 0, BIO_RESET_BYTES);
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atomic_set(&bio->__bi_remaining, 1);
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bio->bi_bdev = bdev;
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if (bio->bi_bdev)
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bio_associate_blkg(bio);
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bio->bi_opf = opf;
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}
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EXPORT_SYMBOL(bio_reset);
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static struct bio *__bio_chain_endio(struct bio *bio)
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{
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struct bio *parent = bio->bi_private;
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if (bio->bi_status && !parent->bi_status)
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parent->bi_status = bio->bi_status;
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bio_put(bio);
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return parent;
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}
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static void bio_chain_endio(struct bio *bio)
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{
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bio_endio(__bio_chain_endio(bio));
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}
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/**
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* bio_chain - chain bio completions
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* @bio: the target bio
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* @parent: the parent bio of @bio
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*
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* The caller won't have a bi_end_io called when @bio completes - instead,
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* @parent's bi_end_io won't be called until both @parent and @bio have
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* completed; the chained bio will also be freed when it completes.
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*
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* The caller must not set bi_private or bi_end_io in @bio.
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*/
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void bio_chain(struct bio *bio, struct bio *parent)
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{
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BUG_ON(bio->bi_private || bio->bi_end_io);
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bio->bi_private = parent;
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bio->bi_end_io = bio_chain_endio;
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bio_inc_remaining(parent);
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}
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EXPORT_SYMBOL(bio_chain);
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struct bio *blk_next_bio(struct bio *bio, struct block_device *bdev,
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unsigned int nr_pages, blk_opf_t opf, gfp_t gfp)
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{
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struct bio *new = bio_alloc(bdev, nr_pages, opf, gfp);
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if (bio) {
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bio_chain(bio, new);
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submit_bio(bio);
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}
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return new;
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}
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EXPORT_SYMBOL_GPL(blk_next_bio);
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|
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static void bio_alloc_rescue(struct work_struct *work)
|
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{
|
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struct bio_set *bs = container_of(work, struct bio_set, rescue_work);
|
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struct bio *bio;
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while (1) {
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spin_lock(&bs->rescue_lock);
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bio = bio_list_pop(&bs->rescue_list);
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spin_unlock(&bs->rescue_lock);
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|
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if (!bio)
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break;
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|
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submit_bio_noacct(bio);
|
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}
|
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}
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|
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static void punt_bios_to_rescuer(struct bio_set *bs)
|
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{
|
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struct bio_list punt, nopunt;
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struct bio *bio;
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|
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if (WARN_ON_ONCE(!bs->rescue_workqueue))
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return;
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/*
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* In order to guarantee forward progress we must punt only bios that
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* were allocated from this bio_set; otherwise, if there was a bio on
|
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* there for a stacking driver higher up in the stack, processing it
|
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* could require allocating bios from this bio_set, and doing that from
|
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* our own rescuer would be bad.
|
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*
|
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* Since bio lists are singly linked, pop them all instead of trying to
|
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* remove from the middle of the list:
|
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*/
|
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|
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bio_list_init(&punt);
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bio_list_init(&nopunt);
|
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|
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while ((bio = bio_list_pop(¤t->bio_list[0])))
|
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bio_list_add(bio->bi_pool == bs ? &punt : &nopunt, bio);
|
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current->bio_list[0] = nopunt;
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|
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bio_list_init(&nopunt);
|
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while ((bio = bio_list_pop(¤t->bio_list[1])))
|
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bio_list_add(bio->bi_pool == bs ? &punt : &nopunt, bio);
|
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current->bio_list[1] = nopunt;
|
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|
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spin_lock(&bs->rescue_lock);
|
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bio_list_merge(&bs->rescue_list, &punt);
|
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spin_unlock(&bs->rescue_lock);
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|
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queue_work(bs->rescue_workqueue, &bs->rescue_work);
|
|
}
|
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|
|
static void bio_alloc_irq_cache_splice(struct bio_alloc_cache *cache)
|
|
{
|
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unsigned long flags;
|
|
|
|
/* cache->free_list must be empty */
|
|
if (WARN_ON_ONCE(cache->free_list))
|
|
return;
|
|
|
|
local_irq_save(flags);
|
|
cache->free_list = cache->free_list_irq;
|
|
cache->free_list_irq = NULL;
|
|
cache->nr += cache->nr_irq;
|
|
cache->nr_irq = 0;
|
|
local_irq_restore(flags);
|
|
}
|
|
|
|
static struct bio *bio_alloc_percpu_cache(struct block_device *bdev,
|
|
unsigned short nr_vecs, blk_opf_t opf, gfp_t gfp,
|
|
struct bio_set *bs)
|
|
{
|
|
struct bio_alloc_cache *cache;
|
|
struct bio *bio;
|
|
|
|
cache = per_cpu_ptr(bs->cache, get_cpu());
|
|
if (!cache->free_list) {
|
|
if (READ_ONCE(cache->nr_irq) >= ALLOC_CACHE_THRESHOLD)
|
|
bio_alloc_irq_cache_splice(cache);
|
|
if (!cache->free_list) {
|
|
put_cpu();
|
|
return NULL;
|
|
}
|
|
}
|
|
bio = cache->free_list;
|
|
cache->free_list = bio->bi_next;
|
|
cache->nr--;
|
|
put_cpu();
|
|
|
|
bio_init(bio, bdev, nr_vecs ? bio->bi_inline_vecs : NULL, nr_vecs, opf);
|
|
bio->bi_pool = bs;
|
|
return bio;
|
|
}
|
|
|
|
/**
|
|
* bio_alloc_bioset - allocate a bio for I/O
|
|
* @bdev: block device to allocate the bio for (can be %NULL)
|
|
* @nr_vecs: number of bvecs to pre-allocate
|
|
* @opf: operation and flags for bio
|
|
* @gfp_mask: the GFP_* mask given to the slab allocator
|
|
* @bs: the bio_set to allocate from.
|
|
*
|
|
* Allocate a bio from the mempools in @bs.
|
|
*
|
|
* If %__GFP_DIRECT_RECLAIM is set then bio_alloc will always be able to
|
|
* allocate a bio. This is due to the mempool guarantees. To make this work,
|
|
* callers must never allocate more than 1 bio at a time from the general pool.
|
|
* Callers that need to allocate more than 1 bio must always submit the
|
|
* previously allocated bio for IO before attempting to allocate a new one.
|
|
* Failure to do so can cause deadlocks under memory pressure.
|
|
*
|
|
* Note that when running under submit_bio_noacct() (i.e. any block driver),
|
|
* bios are not submitted until after you return - see the code in
|
|
* submit_bio_noacct() that converts recursion into iteration, to prevent
|
|
* stack overflows.
|
|
*
|
|
* This would normally mean allocating multiple bios under submit_bio_noacct()
|
|
* would be susceptible to deadlocks, but we have
|
|
* deadlock avoidance code that resubmits any blocked bios from a rescuer
|
|
* thread.
|
|
*
|
|
* However, we do not guarantee forward progress for allocations from other
|
|
* mempools. Doing multiple allocations from the same mempool under
|
|
* submit_bio_noacct() should be avoided - instead, use bio_set's front_pad
|
|
* for per bio allocations.
|
|
*
|
|
* Returns: Pointer to new bio on success, NULL on failure.
|
|
*/
|
|
struct bio *bio_alloc_bioset(struct block_device *bdev, unsigned short nr_vecs,
|
|
blk_opf_t opf, gfp_t gfp_mask,
|
|
struct bio_set *bs)
|
|
{
|
|
gfp_t saved_gfp = gfp_mask;
|
|
struct bio *bio;
|
|
void *p;
|
|
|
|
/* should not use nobvec bioset for nr_vecs > 0 */
|
|
if (WARN_ON_ONCE(!mempool_initialized(&bs->bvec_pool) && nr_vecs > 0))
|
|
return NULL;
|
|
|
|
if (opf & REQ_ALLOC_CACHE) {
|
|
if (bs->cache && nr_vecs <= BIO_INLINE_VECS) {
|
|
bio = bio_alloc_percpu_cache(bdev, nr_vecs, opf,
|
|
gfp_mask, bs);
|
|
if (bio)
|
|
return bio;
|
|
/*
|
|
* No cached bio available, bio returned below marked with
|
|
* REQ_ALLOC_CACHE to particpate in per-cpu alloc cache.
|
|
*/
|
|
} else {
|
|
opf &= ~REQ_ALLOC_CACHE;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* submit_bio_noacct() converts recursion to iteration; this means if
|
|
* we're running beneath it, any bios we allocate and submit will not be
|
|
* submitted (and thus freed) until after we return.
|
|
*
|
|
* This exposes us to a potential deadlock if we allocate multiple bios
|
|
* from the same bio_set() while running underneath submit_bio_noacct().
|
|
* If we were to allocate multiple bios (say a stacking block driver
|
|
* that was splitting bios), we would deadlock if we exhausted the
|
|
* mempool's reserve.
|
|
*
|
|
* We solve this, and guarantee forward progress, with a rescuer
|
|
* workqueue per bio_set. If we go to allocate and there are bios on
|
|
* current->bio_list, we first try the allocation without
|
|
* __GFP_DIRECT_RECLAIM; if that fails, we punt those bios we would be
|
|
* blocking to the rescuer workqueue before we retry with the original
|
|
* gfp_flags.
|
|
*/
|
|
if (current->bio_list &&
|
|
(!bio_list_empty(¤t->bio_list[0]) ||
|
|
!bio_list_empty(¤t->bio_list[1])) &&
|
|
bs->rescue_workqueue)
|
|
gfp_mask &= ~__GFP_DIRECT_RECLAIM;
|
|
|
|
p = mempool_alloc(&bs->bio_pool, gfp_mask);
|
|
if (!p && gfp_mask != saved_gfp) {
|
|
punt_bios_to_rescuer(bs);
|
|
gfp_mask = saved_gfp;
|
|
p = mempool_alloc(&bs->bio_pool, gfp_mask);
|
|
}
|
|
if (unlikely(!p))
|
|
return NULL;
|
|
if (!mempool_is_saturated(&bs->bio_pool))
|
|
opf &= ~REQ_ALLOC_CACHE;
|
|
|
|
bio = p + bs->front_pad;
|
|
if (nr_vecs > BIO_INLINE_VECS) {
|
|
struct bio_vec *bvl = NULL;
|
|
|
|
bvl = bvec_alloc(&bs->bvec_pool, &nr_vecs, gfp_mask);
|
|
if (!bvl && gfp_mask != saved_gfp) {
|
|
punt_bios_to_rescuer(bs);
|
|
gfp_mask = saved_gfp;
|
|
bvl = bvec_alloc(&bs->bvec_pool, &nr_vecs, gfp_mask);
|
|
}
|
|
if (unlikely(!bvl))
|
|
goto err_free;
|
|
|
|
bio_init(bio, bdev, bvl, nr_vecs, opf);
|
|
} else if (nr_vecs) {
|
|
bio_init(bio, bdev, bio->bi_inline_vecs, BIO_INLINE_VECS, opf);
|
|
} else {
|
|
bio_init(bio, bdev, NULL, 0, opf);
|
|
}
|
|
|
|
bio->bi_pool = bs;
|
|
return bio;
|
|
|
|
err_free:
|
|
mempool_free(p, &bs->bio_pool);
|
|
return NULL;
|
|
}
|
|
EXPORT_SYMBOL(bio_alloc_bioset);
|
|
|
|
/**
|
|
* bio_kmalloc - kmalloc a bio
|
|
* @nr_vecs: number of bio_vecs to allocate
|
|
* @gfp_mask: the GFP_* mask given to the slab allocator
|
|
*
|
|
* Use kmalloc to allocate a bio (including bvecs). The bio must be initialized
|
|
* using bio_init() before use. To free a bio returned from this function use
|
|
* kfree() after calling bio_uninit(). A bio returned from this function can
|
|
* be reused by calling bio_uninit() before calling bio_init() again.
|
|
*
|
|
* Note that unlike bio_alloc() or bio_alloc_bioset() allocations from this
|
|
* function are not backed by a mempool can fail. Do not use this function
|
|
* for allocations in the file system I/O path.
|
|
*
|
|
* Returns: Pointer to new bio on success, NULL on failure.
|
|
*/
|
|
struct bio *bio_kmalloc(unsigned short nr_vecs, gfp_t gfp_mask)
|
|
{
|
|
struct bio *bio;
|
|
|
|
if (nr_vecs > UIO_MAXIOV)
|
|
return NULL;
|
|
return kmalloc(struct_size(bio, bi_inline_vecs, nr_vecs), gfp_mask);
|
|
}
|
|
EXPORT_SYMBOL(bio_kmalloc);
|
|
|
|
void zero_fill_bio_iter(struct bio *bio, struct bvec_iter start)
|
|
{
|
|
struct bio_vec bv;
|
|
struct bvec_iter iter;
|
|
|
|
__bio_for_each_segment(bv, bio, iter, start)
|
|
memzero_bvec(&bv);
|
|
}
|
|
EXPORT_SYMBOL(zero_fill_bio_iter);
|
|
|
|
/**
|
|
* bio_truncate - truncate the bio to small size of @new_size
|
|
* @bio: the bio to be truncated
|
|
* @new_size: new size for truncating the bio
|
|
*
|
|
* Description:
|
|
* Truncate the bio to new size of @new_size. If bio_op(bio) is
|
|
* REQ_OP_READ, zero the truncated part. This function should only
|
|
* be used for handling corner cases, such as bio eod.
|
|
*/
|
|
static void bio_truncate(struct bio *bio, unsigned new_size)
|
|
{
|
|
struct bio_vec bv;
|
|
struct bvec_iter iter;
|
|
unsigned int done = 0;
|
|
bool truncated = false;
|
|
|
|
if (new_size >= bio->bi_iter.bi_size)
|
|
return;
|
|
|
|
if (bio_op(bio) != REQ_OP_READ)
|
|
goto exit;
|
|
|
|
bio_for_each_segment(bv, bio, iter) {
|
|
if (done + bv.bv_len > new_size) {
|
|
unsigned offset;
|
|
|
|
if (!truncated)
|
|
offset = new_size - done;
|
|
else
|
|
offset = 0;
|
|
zero_user(bv.bv_page, bv.bv_offset + offset,
|
|
bv.bv_len - offset);
|
|
truncated = true;
|
|
}
|
|
done += bv.bv_len;
|
|
}
|
|
|
|
exit:
|
|
/*
|
|
* Don't touch bvec table here and make it really immutable, since
|
|
* fs bio user has to retrieve all pages via bio_for_each_segment_all
|
|
* in its .end_bio() callback.
|
|
*
|
|
* It is enough to truncate bio by updating .bi_size since we can make
|
|
* correct bvec with the updated .bi_size for drivers.
|
|
*/
|
|
bio->bi_iter.bi_size = new_size;
|
|
}
|
|
|
|
/**
|
|
* guard_bio_eod - truncate a BIO to fit the block device
|
|
* @bio: bio to truncate
|
|
*
|
|
* This allows us to do IO even on the odd last sectors of a device, even if the
|
|
* block size is some multiple of the physical sector size.
|
|
*
|
|
* We'll just truncate the bio to the size of the device, and clear the end of
|
|
* the buffer head manually. Truly out-of-range accesses will turn into actual
|
|
* I/O errors, this only handles the "we need to be able to do I/O at the final
|
|
* sector" case.
|
|
*/
|
|
void guard_bio_eod(struct bio *bio)
|
|
{
|
|
sector_t maxsector = bdev_nr_sectors(bio->bi_bdev);
|
|
|
|
if (!maxsector)
|
|
return;
|
|
|
|
/*
|
|
* If the *whole* IO is past the end of the device,
|
|
* let it through, and the IO layer will turn it into
|
|
* an EIO.
|
|
*/
|
|
if (unlikely(bio->bi_iter.bi_sector >= maxsector))
|
|
return;
|
|
|
|
maxsector -= bio->bi_iter.bi_sector;
|
|
if (likely((bio->bi_iter.bi_size >> 9) <= maxsector))
|
|
return;
|
|
|
|
bio_truncate(bio, maxsector << 9);
|
|
}
|
|
|
|
static int __bio_alloc_cache_prune(struct bio_alloc_cache *cache,
|
|
unsigned int nr)
|
|
{
|
|
unsigned int i = 0;
|
|
struct bio *bio;
|
|
|
|
while ((bio = cache->free_list) != NULL) {
|
|
cache->free_list = bio->bi_next;
|
|
cache->nr--;
|
|
bio_free(bio);
|
|
if (++i == nr)
|
|
break;
|
|
}
|
|
return i;
|
|
}
|
|
|
|
static void bio_alloc_cache_prune(struct bio_alloc_cache *cache,
|
|
unsigned int nr)
|
|
{
|
|
nr -= __bio_alloc_cache_prune(cache, nr);
|
|
if (!READ_ONCE(cache->free_list)) {
|
|
bio_alloc_irq_cache_splice(cache);
|
|
__bio_alloc_cache_prune(cache, nr);
|
|
}
|
|
}
|
|
|
|
static int bio_cpu_dead(unsigned int cpu, struct hlist_node *node)
|
|
{
|
|
struct bio_set *bs;
|
|
|
|
bs = hlist_entry_safe(node, struct bio_set, cpuhp_dead);
|
|
if (bs->cache) {
|
|
struct bio_alloc_cache *cache = per_cpu_ptr(bs->cache, cpu);
|
|
|
|
bio_alloc_cache_prune(cache, -1U);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static void bio_alloc_cache_destroy(struct bio_set *bs)
|
|
{
|
|
int cpu;
|
|
|
|
if (!bs->cache)
|
|
return;
|
|
|
|
cpuhp_state_remove_instance_nocalls(CPUHP_BIO_DEAD, &bs->cpuhp_dead);
|
|
for_each_possible_cpu(cpu) {
|
|
struct bio_alloc_cache *cache;
|
|
|
|
cache = per_cpu_ptr(bs->cache, cpu);
|
|
bio_alloc_cache_prune(cache, -1U);
|
|
}
|
|
free_percpu(bs->cache);
|
|
bs->cache = NULL;
|
|
}
|
|
|
|
static inline void bio_put_percpu_cache(struct bio *bio)
|
|
{
|
|
struct bio_alloc_cache *cache;
|
|
|
|
cache = per_cpu_ptr(bio->bi_pool->cache, get_cpu());
|
|
if (READ_ONCE(cache->nr_irq) + cache->nr > ALLOC_CACHE_MAX)
|
|
goto out_free;
|
|
|
|
if (in_task()) {
|
|
bio_uninit(bio);
|
|
bio->bi_next = cache->free_list;
|
|
/* Not necessary but helps not to iopoll already freed bios */
|
|
bio->bi_bdev = NULL;
|
|
cache->free_list = bio;
|
|
cache->nr++;
|
|
} else if (in_hardirq()) {
|
|
lockdep_assert_irqs_disabled();
|
|
|
|
bio_uninit(bio);
|
|
bio->bi_next = cache->free_list_irq;
|
|
cache->free_list_irq = bio;
|
|
cache->nr_irq++;
|
|
} else {
|
|
goto out_free;
|
|
}
|
|
put_cpu();
|
|
return;
|
|
out_free:
|
|
put_cpu();
|
|
bio_free(bio);
|
|
}
|
|
|
|
/**
|
|
* bio_put - release a reference to a bio
|
|
* @bio: bio to release reference to
|
|
*
|
|
* Description:
|
|
* Put a reference to a &struct bio, either one you have gotten with
|
|
* bio_alloc, bio_get or bio_clone_*. The last put of a bio will free it.
|
|
**/
|
|
void bio_put(struct bio *bio)
|
|
{
|
|
if (unlikely(bio_flagged(bio, BIO_REFFED))) {
|
|
BUG_ON(!atomic_read(&bio->__bi_cnt));
|
|
if (!atomic_dec_and_test(&bio->__bi_cnt))
|
|
return;
|
|
}
|
|
if (bio->bi_opf & REQ_ALLOC_CACHE)
|
|
bio_put_percpu_cache(bio);
|
|
else
|
|
bio_free(bio);
|
|
}
|
|
EXPORT_SYMBOL(bio_put);
|
|
|
|
static int __bio_clone(struct bio *bio, struct bio *bio_src, gfp_t gfp)
|
|
{
|
|
bio_set_flag(bio, BIO_CLONED);
|
|
bio->bi_ioprio = bio_src->bi_ioprio;
|
|
bio->bi_write_hint = bio_src->bi_write_hint;
|
|
bio->bi_iter = bio_src->bi_iter;
|
|
|
|
if (bio->bi_bdev) {
|
|
if (bio->bi_bdev == bio_src->bi_bdev &&
|
|
bio_flagged(bio_src, BIO_REMAPPED))
|
|
bio_set_flag(bio, BIO_REMAPPED);
|
|
bio_clone_blkg_association(bio, bio_src);
|
|
}
|
|
|
|
if (bio_crypt_clone(bio, bio_src, gfp) < 0)
|
|
return -ENOMEM;
|
|
if (bio_integrity(bio_src) &&
|
|
bio_integrity_clone(bio, bio_src, gfp) < 0)
|
|
return -ENOMEM;
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* bio_alloc_clone - clone a bio that shares the original bio's biovec
|
|
* @bdev: block_device to clone onto
|
|
* @bio_src: bio to clone from
|
|
* @gfp: allocation priority
|
|
* @bs: bio_set to allocate from
|
|
*
|
|
* Allocate a new bio that is a clone of @bio_src. The caller owns the returned
|
|
* bio, but not the actual data it points to.
|
|
*
|
|
* The caller must ensure that the return bio is not freed before @bio_src.
|
|
*/
|
|
struct bio *bio_alloc_clone(struct block_device *bdev, struct bio *bio_src,
|
|
gfp_t gfp, struct bio_set *bs)
|
|
{
|
|
struct bio *bio;
|
|
|
|
bio = bio_alloc_bioset(bdev, 0, bio_src->bi_opf, gfp, bs);
|
|
if (!bio)
|
|
return NULL;
|
|
|
|
if (__bio_clone(bio, bio_src, gfp) < 0) {
|
|
bio_put(bio);
|
|
return NULL;
|
|
}
|
|
bio->bi_io_vec = bio_src->bi_io_vec;
|
|
|
|
return bio;
|
|
}
|
|
EXPORT_SYMBOL(bio_alloc_clone);
|
|
|
|
/**
|
|
* bio_init_clone - clone a bio that shares the original bio's biovec
|
|
* @bdev: block_device to clone onto
|
|
* @bio: bio to clone into
|
|
* @bio_src: bio to clone from
|
|
* @gfp: allocation priority
|
|
*
|
|
* Initialize a new bio in caller provided memory that is a clone of @bio_src.
|
|
* The caller owns the returned bio, but not the actual data it points to.
|
|
*
|
|
* The caller must ensure that @bio_src is not freed before @bio.
|
|
*/
|
|
int bio_init_clone(struct block_device *bdev, struct bio *bio,
|
|
struct bio *bio_src, gfp_t gfp)
|
|
{
|
|
int ret;
|
|
|
|
bio_init(bio, bdev, bio_src->bi_io_vec, 0, bio_src->bi_opf);
|
|
ret = __bio_clone(bio, bio_src, gfp);
|
|
if (ret)
|
|
bio_uninit(bio);
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(bio_init_clone);
|
|
|
|
/**
|
|
* bio_full - check if the bio is full
|
|
* @bio: bio to check
|
|
* @len: length of one segment to be added
|
|
*
|
|
* Return true if @bio is full and one segment with @len bytes can't be
|
|
* added to the bio, otherwise return false
|
|
*/
|
|
static inline bool bio_full(struct bio *bio, unsigned len)
|
|
{
|
|
if (bio->bi_vcnt >= bio->bi_max_vecs)
|
|
return true;
|
|
if (bio->bi_iter.bi_size > UINT_MAX - len)
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
static bool bvec_try_merge_page(struct bio_vec *bv, struct page *page,
|
|
unsigned int len, unsigned int off, bool *same_page)
|
|
{
|
|
size_t bv_end = bv->bv_offset + bv->bv_len;
|
|
phys_addr_t vec_end_addr = page_to_phys(bv->bv_page) + bv_end - 1;
|
|
phys_addr_t page_addr = page_to_phys(page);
|
|
|
|
if (vec_end_addr + 1 != page_addr + off)
|
|
return false;
|
|
if (xen_domain() && !xen_biovec_phys_mergeable(bv, page))
|
|
return false;
|
|
if (!zone_device_pages_have_same_pgmap(bv->bv_page, page))
|
|
return false;
|
|
|
|
*same_page = ((vec_end_addr & PAGE_MASK) == page_addr);
|
|
if (!*same_page) {
|
|
if (IS_ENABLED(CONFIG_KMSAN))
|
|
return false;
|
|
if (bv->bv_page + bv_end / PAGE_SIZE != page + off / PAGE_SIZE)
|
|
return false;
|
|
}
|
|
|
|
bv->bv_len += len;
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Try to merge a page into a segment, while obeying the hardware segment
|
|
* size limit. This is not for normal read/write bios, but for passthrough
|
|
* or Zone Append operations that we can't split.
|
|
*/
|
|
bool bvec_try_merge_hw_page(struct request_queue *q, struct bio_vec *bv,
|
|
struct page *page, unsigned len, unsigned offset,
|
|
bool *same_page)
|
|
{
|
|
unsigned long mask = queue_segment_boundary(q);
|
|
phys_addr_t addr1 = page_to_phys(bv->bv_page) + bv->bv_offset;
|
|
phys_addr_t addr2 = page_to_phys(page) + offset + len - 1;
|
|
|
|
if ((addr1 | mask) != (addr2 | mask))
|
|
return false;
|
|
if (len > queue_max_segment_size(q) - bv->bv_len)
|
|
return false;
|
|
return bvec_try_merge_page(bv, page, len, offset, same_page);
|
|
}
|
|
|
|
/**
|
|
* bio_add_hw_page - attempt to add a page to a bio with hw constraints
|
|
* @q: the target queue
|
|
* @bio: destination bio
|
|
* @page: page to add
|
|
* @len: vec entry length
|
|
* @offset: vec entry offset
|
|
* @max_sectors: maximum number of sectors that can be added
|
|
* @same_page: return if the segment has been merged inside the same page
|
|
*
|
|
* Add a page to a bio while respecting the hardware max_sectors, max_segment
|
|
* and gap limitations.
|
|
*/
|
|
int bio_add_hw_page(struct request_queue *q, struct bio *bio,
|
|
struct page *page, unsigned int len, unsigned int offset,
|
|
unsigned int max_sectors, bool *same_page)
|
|
{
|
|
unsigned int max_size = max_sectors << SECTOR_SHIFT;
|
|
|
|
if (WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED)))
|
|
return 0;
|
|
|
|
len = min3(len, max_size, queue_max_segment_size(q));
|
|
if (len > max_size - bio->bi_iter.bi_size)
|
|
return 0;
|
|
|
|
if (bio->bi_vcnt > 0) {
|
|
struct bio_vec *bv = &bio->bi_io_vec[bio->bi_vcnt - 1];
|
|
|
|
if (bvec_try_merge_hw_page(q, bv, page, len, offset,
|
|
same_page)) {
|
|
bio->bi_iter.bi_size += len;
|
|
return len;
|
|
}
|
|
|
|
if (bio->bi_vcnt >=
|
|
min(bio->bi_max_vecs, queue_max_segments(q)))
|
|
return 0;
|
|
|
|
/*
|
|
* If the queue doesn't support SG gaps and adding this segment
|
|
* would create a gap, disallow it.
|
|
*/
|
|
if (bvec_gap_to_prev(&q->limits, bv, offset))
|
|
return 0;
|
|
}
|
|
|
|
bvec_set_page(&bio->bi_io_vec[bio->bi_vcnt], page, len, offset);
|
|
bio->bi_vcnt++;
|
|
bio->bi_iter.bi_size += len;
|
|
return len;
|
|
}
|
|
|
|
/**
|
|
* bio_add_pc_page - attempt to add page to passthrough bio
|
|
* @q: the target queue
|
|
* @bio: destination bio
|
|
* @page: page to add
|
|
* @len: vec entry length
|
|
* @offset: vec entry offset
|
|
*
|
|
* Attempt to add a page to the bio_vec maplist. This can fail for a
|
|
* number of reasons, such as the bio being full or target block device
|
|
* limitations. The target block device must allow bio's up to PAGE_SIZE,
|
|
* so it is always possible to add a single page to an empty bio.
|
|
*
|
|
* This should only be used by passthrough bios.
|
|
*/
|
|
int bio_add_pc_page(struct request_queue *q, struct bio *bio,
|
|
struct page *page, unsigned int len, unsigned int offset)
|
|
{
|
|
bool same_page = false;
|
|
return bio_add_hw_page(q, bio, page, len, offset,
|
|
queue_max_hw_sectors(q), &same_page);
|
|
}
|
|
EXPORT_SYMBOL(bio_add_pc_page);
|
|
|
|
/**
|
|
* bio_add_zone_append_page - attempt to add page to zone-append bio
|
|
* @bio: destination bio
|
|
* @page: page to add
|
|
* @len: vec entry length
|
|
* @offset: vec entry offset
|
|
*
|
|
* Attempt to add a page to the bio_vec maplist of a bio that will be submitted
|
|
* for a zone-append request. This can fail for a number of reasons, such as the
|
|
* bio being full or the target block device is not a zoned block device or
|
|
* other limitations of the target block device. The target block device must
|
|
* allow bio's up to PAGE_SIZE, so it is always possible to add a single page
|
|
* to an empty bio.
|
|
*
|
|
* Returns: number of bytes added to the bio, or 0 in case of a failure.
|
|
*/
|
|
int bio_add_zone_append_page(struct bio *bio, struct page *page,
|
|
unsigned int len, unsigned int offset)
|
|
{
|
|
struct request_queue *q = bdev_get_queue(bio->bi_bdev);
|
|
bool same_page = false;
|
|
|
|
if (WARN_ON_ONCE(bio_op(bio) != REQ_OP_ZONE_APPEND))
|
|
return 0;
|
|
|
|
if (WARN_ON_ONCE(!bdev_is_zoned(bio->bi_bdev)))
|
|
return 0;
|
|
|
|
return bio_add_hw_page(q, bio, page, len, offset,
|
|
queue_max_zone_append_sectors(q), &same_page);
|
|
}
|
|
EXPORT_SYMBOL_GPL(bio_add_zone_append_page);
|
|
|
|
/**
|
|
* __bio_add_page - add page(s) to a bio in a new segment
|
|
* @bio: destination bio
|
|
* @page: start page to add
|
|
* @len: length of the data to add, may cross pages
|
|
* @off: offset of the data relative to @page, may cross pages
|
|
*
|
|
* Add the data at @page + @off to @bio as a new bvec. The caller must ensure
|
|
* that @bio has space for another bvec.
|
|
*/
|
|
void __bio_add_page(struct bio *bio, struct page *page,
|
|
unsigned int len, unsigned int off)
|
|
{
|
|
WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED));
|
|
WARN_ON_ONCE(bio_full(bio, len));
|
|
|
|
bvec_set_page(&bio->bi_io_vec[bio->bi_vcnt], page, len, off);
|
|
bio->bi_iter.bi_size += len;
|
|
bio->bi_vcnt++;
|
|
}
|
|
EXPORT_SYMBOL_GPL(__bio_add_page);
|
|
|
|
/**
|
|
* bio_add_page - attempt to add page(s) to bio
|
|
* @bio: destination bio
|
|
* @page: start page to add
|
|
* @len: vec entry length, may cross pages
|
|
* @offset: vec entry offset relative to @page, may cross pages
|
|
*
|
|
* Attempt to add page(s) to the bio_vec maplist. This will only fail
|
|
* if either bio->bi_vcnt == bio->bi_max_vecs or it's a cloned bio.
|
|
*/
|
|
int bio_add_page(struct bio *bio, struct page *page,
|
|
unsigned int len, unsigned int offset)
|
|
{
|
|
bool same_page = false;
|
|
|
|
if (WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED)))
|
|
return 0;
|
|
if (bio->bi_iter.bi_size > UINT_MAX - len)
|
|
return 0;
|
|
|
|
if (bio->bi_vcnt > 0 &&
|
|
bvec_try_merge_page(&bio->bi_io_vec[bio->bi_vcnt - 1],
|
|
page, len, offset, &same_page)) {
|
|
bio->bi_iter.bi_size += len;
|
|
return len;
|
|
}
|
|
|
|
if (bio->bi_vcnt >= bio->bi_max_vecs)
|
|
return 0;
|
|
__bio_add_page(bio, page, len, offset);
|
|
return len;
|
|
}
|
|
EXPORT_SYMBOL(bio_add_page);
|
|
|
|
void bio_add_folio_nofail(struct bio *bio, struct folio *folio, size_t len,
|
|
size_t off)
|
|
{
|
|
WARN_ON_ONCE(len > UINT_MAX);
|
|
WARN_ON_ONCE(off > UINT_MAX);
|
|
__bio_add_page(bio, &folio->page, len, off);
|
|
}
|
|
|
|
/**
|
|
* bio_add_folio - Attempt to add part of a folio to a bio.
|
|
* @bio: BIO to add to.
|
|
* @folio: Folio to add.
|
|
* @len: How many bytes from the folio to add.
|
|
* @off: First byte in this folio to add.
|
|
*
|
|
* Filesystems that use folios can call this function instead of calling
|
|
* bio_add_page() for each page in the folio. If @off is bigger than
|
|
* PAGE_SIZE, this function can create a bio_vec that starts in a page
|
|
* after the bv_page. BIOs do not support folios that are 4GiB or larger.
|
|
*
|
|
* Return: Whether the addition was successful.
|
|
*/
|
|
bool bio_add_folio(struct bio *bio, struct folio *folio, size_t len,
|
|
size_t off)
|
|
{
|
|
if (len > UINT_MAX || off > UINT_MAX)
|
|
return false;
|
|
return bio_add_page(bio, &folio->page, len, off) > 0;
|
|
}
|
|
EXPORT_SYMBOL(bio_add_folio);
|
|
|
|
void __bio_release_pages(struct bio *bio, bool mark_dirty)
|
|
{
|
|
struct folio_iter fi;
|
|
|
|
bio_for_each_folio_all(fi, bio) {
|
|
struct page *page;
|
|
size_t nr_pages;
|
|
|
|
if (mark_dirty) {
|
|
folio_lock(fi.folio);
|
|
folio_mark_dirty(fi.folio);
|
|
folio_unlock(fi.folio);
|
|
}
|
|
page = folio_page(fi.folio, fi.offset / PAGE_SIZE);
|
|
nr_pages = (fi.offset + fi.length - 1) / PAGE_SIZE -
|
|
fi.offset / PAGE_SIZE + 1;
|
|
do {
|
|
bio_release_page(bio, page++);
|
|
} while (--nr_pages != 0);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL_GPL(__bio_release_pages);
|
|
|
|
void bio_iov_bvec_set(struct bio *bio, struct iov_iter *iter)
|
|
{
|
|
size_t size = iov_iter_count(iter);
|
|
|
|
WARN_ON_ONCE(bio->bi_max_vecs);
|
|
|
|
if (bio_op(bio) == REQ_OP_ZONE_APPEND) {
|
|
struct request_queue *q = bdev_get_queue(bio->bi_bdev);
|
|
size_t max_sectors = queue_max_zone_append_sectors(q);
|
|
|
|
size = min(size, max_sectors << SECTOR_SHIFT);
|
|
}
|
|
|
|
bio->bi_vcnt = iter->nr_segs;
|
|
bio->bi_io_vec = (struct bio_vec *)iter->bvec;
|
|
bio->bi_iter.bi_bvec_done = iter->iov_offset;
|
|
bio->bi_iter.bi_size = size;
|
|
bio_set_flag(bio, BIO_CLONED);
|
|
}
|
|
|
|
static int bio_iov_add_page(struct bio *bio, struct page *page,
|
|
unsigned int len, unsigned int offset)
|
|
{
|
|
bool same_page = false;
|
|
|
|
if (WARN_ON_ONCE(bio->bi_iter.bi_size > UINT_MAX - len))
|
|
return -EIO;
|
|
|
|
if (bio->bi_vcnt > 0 &&
|
|
bvec_try_merge_page(&bio->bi_io_vec[bio->bi_vcnt - 1],
|
|
page, len, offset, &same_page)) {
|
|
bio->bi_iter.bi_size += len;
|
|
if (same_page)
|
|
bio_release_page(bio, page);
|
|
return 0;
|
|
}
|
|
__bio_add_page(bio, page, len, offset);
|
|
return 0;
|
|
}
|
|
|
|
static int bio_iov_add_zone_append_page(struct bio *bio, struct page *page,
|
|
unsigned int len, unsigned int offset)
|
|
{
|
|
struct request_queue *q = bdev_get_queue(bio->bi_bdev);
|
|
bool same_page = false;
|
|
|
|
if (bio_add_hw_page(q, bio, page, len, offset,
|
|
queue_max_zone_append_sectors(q), &same_page) != len)
|
|
return -EINVAL;
|
|
if (same_page)
|
|
bio_release_page(bio, page);
|
|
return 0;
|
|
}
|
|
|
|
#define PAGE_PTRS_PER_BVEC (sizeof(struct bio_vec) / sizeof(struct page *))
|
|
|
|
/**
|
|
* __bio_iov_iter_get_pages - pin user or kernel pages and add them to a bio
|
|
* @bio: bio to add pages to
|
|
* @iter: iov iterator describing the region to be mapped
|
|
*
|
|
* Extracts pages from *iter and appends them to @bio's bvec array. The pages
|
|
* will have to be cleaned up in the way indicated by the BIO_PAGE_PINNED flag.
|
|
* For a multi-segment *iter, this function only adds pages from the next
|
|
* non-empty segment of the iov iterator.
|
|
*/
|
|
static int __bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter)
|
|
{
|
|
iov_iter_extraction_t extraction_flags = 0;
|
|
unsigned short nr_pages = bio->bi_max_vecs - bio->bi_vcnt;
|
|
unsigned short entries_left = bio->bi_max_vecs - bio->bi_vcnt;
|
|
struct bio_vec *bv = bio->bi_io_vec + bio->bi_vcnt;
|
|
struct page **pages = (struct page **)bv;
|
|
ssize_t size, left;
|
|
unsigned len, i = 0;
|
|
size_t offset;
|
|
int ret = 0;
|
|
|
|
/*
|
|
* Move page array up in the allocated memory for the bio vecs as far as
|
|
* possible so that we can start filling biovecs from the beginning
|
|
* without overwriting the temporary page array.
|
|
*/
|
|
BUILD_BUG_ON(PAGE_PTRS_PER_BVEC < 2);
|
|
pages += entries_left * (PAGE_PTRS_PER_BVEC - 1);
|
|
|
|
if (bio->bi_bdev && blk_queue_pci_p2pdma(bio->bi_bdev->bd_disk->queue))
|
|
extraction_flags |= ITER_ALLOW_P2PDMA;
|
|
|
|
/*
|
|
* Each segment in the iov is required to be a block size multiple.
|
|
* However, we may not be able to get the entire segment if it spans
|
|
* more pages than bi_max_vecs allows, so we have to ALIGN_DOWN the
|
|
* result to ensure the bio's total size is correct. The remainder of
|
|
* the iov data will be picked up in the next bio iteration.
|
|
*/
|
|
size = iov_iter_extract_pages(iter, &pages,
|
|
UINT_MAX - bio->bi_iter.bi_size,
|
|
nr_pages, extraction_flags, &offset);
|
|
if (unlikely(size <= 0))
|
|
return size ? size : -EFAULT;
|
|
|
|
nr_pages = DIV_ROUND_UP(offset + size, PAGE_SIZE);
|
|
|
|
if (bio->bi_bdev) {
|
|
size_t trim = size & (bdev_logical_block_size(bio->bi_bdev) - 1);
|
|
iov_iter_revert(iter, trim);
|
|
size -= trim;
|
|
}
|
|
|
|
if (unlikely(!size)) {
|
|
ret = -EFAULT;
|
|
goto out;
|
|
}
|
|
|
|
for (left = size, i = 0; left > 0; left -= len, i++) {
|
|
struct page *page = pages[i];
|
|
|
|
len = min_t(size_t, PAGE_SIZE - offset, left);
|
|
if (bio_op(bio) == REQ_OP_ZONE_APPEND) {
|
|
ret = bio_iov_add_zone_append_page(bio, page, len,
|
|
offset);
|
|
if (ret)
|
|
break;
|
|
} else
|
|
bio_iov_add_page(bio, page, len, offset);
|
|
|
|
offset = 0;
|
|
}
|
|
|
|
iov_iter_revert(iter, left);
|
|
out:
|
|
while (i < nr_pages)
|
|
bio_release_page(bio, pages[i++]);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* bio_iov_iter_get_pages - add user or kernel pages to a bio
|
|
* @bio: bio to add pages to
|
|
* @iter: iov iterator describing the region to be added
|
|
*
|
|
* This takes either an iterator pointing to user memory, or one pointing to
|
|
* kernel pages (BVEC iterator). If we're adding user pages, we pin them and
|
|
* map them into the kernel. On IO completion, the caller should put those
|
|
* pages. For bvec based iterators bio_iov_iter_get_pages() uses the provided
|
|
* bvecs rather than copying them. Hence anyone issuing kiocb based IO needs
|
|
* to ensure the bvecs and pages stay referenced until the submitted I/O is
|
|
* completed by a call to ->ki_complete() or returns with an error other than
|
|
* -EIOCBQUEUED. The caller needs to check if the bio is flagged BIO_NO_PAGE_REF
|
|
* on IO completion. If it isn't, then pages should be released.
|
|
*
|
|
* The function tries, but does not guarantee, to pin as many pages as
|
|
* fit into the bio, or are requested in @iter, whatever is smaller. If
|
|
* MM encounters an error pinning the requested pages, it stops. Error
|
|
* is returned only if 0 pages could be pinned.
|
|
*/
|
|
int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter)
|
|
{
|
|
int ret = 0;
|
|
|
|
if (WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED)))
|
|
return -EIO;
|
|
|
|
if (iov_iter_is_bvec(iter)) {
|
|
bio_iov_bvec_set(bio, iter);
|
|
iov_iter_advance(iter, bio->bi_iter.bi_size);
|
|
return 0;
|
|
}
|
|
|
|
if (iov_iter_extract_will_pin(iter))
|
|
bio_set_flag(bio, BIO_PAGE_PINNED);
|
|
do {
|
|
ret = __bio_iov_iter_get_pages(bio, iter);
|
|
} while (!ret && iov_iter_count(iter) && !bio_full(bio, 0));
|
|
|
|
return bio->bi_vcnt ? 0 : ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(bio_iov_iter_get_pages);
|
|
|
|
static void submit_bio_wait_endio(struct bio *bio)
|
|
{
|
|
complete(bio->bi_private);
|
|
}
|
|
|
|
/**
|
|
* submit_bio_wait - submit a bio, and wait until it completes
|
|
* @bio: The &struct bio which describes the I/O
|
|
*
|
|
* Simple wrapper around submit_bio(). Returns 0 on success, or the error from
|
|
* bio_endio() on failure.
|
|
*
|
|
* WARNING: Unlike to how submit_bio() is usually used, this function does not
|
|
* result in bio reference to be consumed. The caller must drop the reference
|
|
* on his own.
|
|
*/
|
|
int submit_bio_wait(struct bio *bio)
|
|
{
|
|
DECLARE_COMPLETION_ONSTACK_MAP(done,
|
|
bio->bi_bdev->bd_disk->lockdep_map);
|
|
|
|
bio->bi_private = &done;
|
|
bio->bi_end_io = submit_bio_wait_endio;
|
|
bio->bi_opf |= REQ_SYNC;
|
|
submit_bio(bio);
|
|
blk_wait_io(&done);
|
|
|
|
return blk_status_to_errno(bio->bi_status);
|
|
}
|
|
EXPORT_SYMBOL(submit_bio_wait);
|
|
|
|
void __bio_advance(struct bio *bio, unsigned bytes)
|
|
{
|
|
if (bio_integrity(bio))
|
|
bio_integrity_advance(bio, bytes);
|
|
|
|
bio_crypt_advance(bio, bytes);
|
|
bio_advance_iter(bio, &bio->bi_iter, bytes);
|
|
}
|
|
EXPORT_SYMBOL(__bio_advance);
|
|
|
|
void bio_copy_data_iter(struct bio *dst, struct bvec_iter *dst_iter,
|
|
struct bio *src, struct bvec_iter *src_iter)
|
|
{
|
|
while (src_iter->bi_size && dst_iter->bi_size) {
|
|
struct bio_vec src_bv = bio_iter_iovec(src, *src_iter);
|
|
struct bio_vec dst_bv = bio_iter_iovec(dst, *dst_iter);
|
|
unsigned int bytes = min(src_bv.bv_len, dst_bv.bv_len);
|
|
void *src_buf = bvec_kmap_local(&src_bv);
|
|
void *dst_buf = bvec_kmap_local(&dst_bv);
|
|
|
|
memcpy(dst_buf, src_buf, bytes);
|
|
|
|
kunmap_local(dst_buf);
|
|
kunmap_local(src_buf);
|
|
|
|
bio_advance_iter_single(src, src_iter, bytes);
|
|
bio_advance_iter_single(dst, dst_iter, bytes);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(bio_copy_data_iter);
|
|
|
|
/**
|
|
* bio_copy_data - copy contents of data buffers from one bio to another
|
|
* @src: source bio
|
|
* @dst: destination bio
|
|
*
|
|
* Stops when it reaches the end of either @src or @dst - that is, copies
|
|
* min(src->bi_size, dst->bi_size) bytes (or the equivalent for lists of bios).
|
|
*/
|
|
void bio_copy_data(struct bio *dst, struct bio *src)
|
|
{
|
|
struct bvec_iter src_iter = src->bi_iter;
|
|
struct bvec_iter dst_iter = dst->bi_iter;
|
|
|
|
bio_copy_data_iter(dst, &dst_iter, src, &src_iter);
|
|
}
|
|
EXPORT_SYMBOL(bio_copy_data);
|
|
|
|
void bio_free_pages(struct bio *bio)
|
|
{
|
|
struct bio_vec *bvec;
|
|
struct bvec_iter_all iter_all;
|
|
|
|
bio_for_each_segment_all(bvec, bio, iter_all)
|
|
__free_page(bvec->bv_page);
|
|
}
|
|
EXPORT_SYMBOL(bio_free_pages);
|
|
|
|
/*
|
|
* bio_set_pages_dirty() and bio_check_pages_dirty() are support functions
|
|
* for performing direct-IO in BIOs.
|
|
*
|
|
* The problem is that we cannot run folio_mark_dirty() from interrupt context
|
|
* because the required locks are not interrupt-safe. So what we can do is to
|
|
* mark the pages dirty _before_ performing IO. And in interrupt context,
|
|
* check that the pages are still dirty. If so, fine. If not, redirty them
|
|
* in process context.
|
|
*
|
|
* Note that this code is very hard to test under normal circumstances because
|
|
* direct-io pins the pages with get_user_pages(). This makes
|
|
* is_page_cache_freeable return false, and the VM will not clean the pages.
|
|
* But other code (eg, flusher threads) could clean the pages if they are mapped
|
|
* pagecache.
|
|
*
|
|
* Simply disabling the call to bio_set_pages_dirty() is a good way to test the
|
|
* deferred bio dirtying paths.
|
|
*/
|
|
|
|
/*
|
|
* bio_set_pages_dirty() will mark all the bio's pages as dirty.
|
|
*/
|
|
void bio_set_pages_dirty(struct bio *bio)
|
|
{
|
|
struct folio_iter fi;
|
|
|
|
bio_for_each_folio_all(fi, bio) {
|
|
folio_lock(fi.folio);
|
|
folio_mark_dirty(fi.folio);
|
|
folio_unlock(fi.folio);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL_GPL(bio_set_pages_dirty);
|
|
|
|
/*
|
|
* bio_check_pages_dirty() will check that all the BIO's pages are still dirty.
|
|
* If they are, then fine. If, however, some pages are clean then they must
|
|
* have been written out during the direct-IO read. So we take another ref on
|
|
* the BIO and re-dirty the pages in process context.
|
|
*
|
|
* It is expected that bio_check_pages_dirty() will wholly own the BIO from
|
|
* here on. It will unpin each page and will run one bio_put() against the
|
|
* BIO.
|
|
*/
|
|
|
|
static void bio_dirty_fn(struct work_struct *work);
|
|
|
|
static DECLARE_WORK(bio_dirty_work, bio_dirty_fn);
|
|
static DEFINE_SPINLOCK(bio_dirty_lock);
|
|
static struct bio *bio_dirty_list;
|
|
|
|
/*
|
|
* This runs in process context
|
|
*/
|
|
static void bio_dirty_fn(struct work_struct *work)
|
|
{
|
|
struct bio *bio, *next;
|
|
|
|
spin_lock_irq(&bio_dirty_lock);
|
|
next = bio_dirty_list;
|
|
bio_dirty_list = NULL;
|
|
spin_unlock_irq(&bio_dirty_lock);
|
|
|
|
while ((bio = next) != NULL) {
|
|
next = bio->bi_private;
|
|
|
|
bio_release_pages(bio, true);
|
|
bio_put(bio);
|
|
}
|
|
}
|
|
|
|
void bio_check_pages_dirty(struct bio *bio)
|
|
{
|
|
struct folio_iter fi;
|
|
unsigned long flags;
|
|
|
|
bio_for_each_folio_all(fi, bio) {
|
|
if (!folio_test_dirty(fi.folio))
|
|
goto defer;
|
|
}
|
|
|
|
bio_release_pages(bio, false);
|
|
bio_put(bio);
|
|
return;
|
|
defer:
|
|
spin_lock_irqsave(&bio_dirty_lock, flags);
|
|
bio->bi_private = bio_dirty_list;
|
|
bio_dirty_list = bio;
|
|
spin_unlock_irqrestore(&bio_dirty_lock, flags);
|
|
schedule_work(&bio_dirty_work);
|
|
}
|
|
EXPORT_SYMBOL_GPL(bio_check_pages_dirty);
|
|
|
|
static inline bool bio_remaining_done(struct bio *bio)
|
|
{
|
|
/*
|
|
* If we're not chaining, then ->__bi_remaining is always 1 and
|
|
* we always end io on the first invocation.
|
|
*/
|
|
if (!bio_flagged(bio, BIO_CHAIN))
|
|
return true;
|
|
|
|
BUG_ON(atomic_read(&bio->__bi_remaining) <= 0);
|
|
|
|
if (atomic_dec_and_test(&bio->__bi_remaining)) {
|
|
bio_clear_flag(bio, BIO_CHAIN);
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* bio_endio - end I/O on a bio
|
|
* @bio: bio
|
|
*
|
|
* Description:
|
|
* bio_endio() will end I/O on the whole bio. bio_endio() is the preferred
|
|
* way to end I/O on a bio. No one should call bi_end_io() directly on a
|
|
* bio unless they own it and thus know that it has an end_io function.
|
|
*
|
|
* bio_endio() can be called several times on a bio that has been chained
|
|
* using bio_chain(). The ->bi_end_io() function will only be called the
|
|
* last time.
|
|
**/
|
|
void bio_endio(struct bio *bio)
|
|
{
|
|
again:
|
|
if (!bio_remaining_done(bio))
|
|
return;
|
|
if (!bio_integrity_endio(bio))
|
|
return;
|
|
|
|
rq_qos_done_bio(bio);
|
|
|
|
if (bio->bi_bdev && bio_flagged(bio, BIO_TRACE_COMPLETION)) {
|
|
trace_block_bio_complete(bdev_get_queue(bio->bi_bdev), bio);
|
|
bio_clear_flag(bio, BIO_TRACE_COMPLETION);
|
|
}
|
|
|
|
/*
|
|
* Need to have a real endio function for chained bios, otherwise
|
|
* various corner cases will break (like stacking block devices that
|
|
* save/restore bi_end_io) - however, we want to avoid unbounded
|
|
* recursion and blowing the stack. Tail call optimization would
|
|
* handle this, but compiling with frame pointers also disables
|
|
* gcc's sibling call optimization.
|
|
*/
|
|
if (bio->bi_end_io == bio_chain_endio) {
|
|
bio = __bio_chain_endio(bio);
|
|
goto again;
|
|
}
|
|
|
|
blk_throtl_bio_endio(bio);
|
|
/* release cgroup info */
|
|
bio_uninit(bio);
|
|
if (bio->bi_end_io)
|
|
bio->bi_end_io(bio);
|
|
}
|
|
EXPORT_SYMBOL(bio_endio);
|
|
|
|
/**
|
|
* bio_split - split a bio
|
|
* @bio: bio to split
|
|
* @sectors: number of sectors to split from the front of @bio
|
|
* @gfp: gfp mask
|
|
* @bs: bio set to allocate from
|
|
*
|
|
* Allocates and returns a new bio which represents @sectors from the start of
|
|
* @bio, and updates @bio to represent the remaining sectors.
|
|
*
|
|
* Unless this is a discard request the newly allocated bio will point
|
|
* to @bio's bi_io_vec. It is the caller's responsibility to ensure that
|
|
* neither @bio nor @bs are freed before the split bio.
|
|
*/
|
|
struct bio *bio_split(struct bio *bio, int sectors,
|
|
gfp_t gfp, struct bio_set *bs)
|
|
{
|
|
struct bio *split;
|
|
|
|
BUG_ON(sectors <= 0);
|
|
BUG_ON(sectors >= bio_sectors(bio));
|
|
|
|
/* Zone append commands cannot be split */
|
|
if (WARN_ON_ONCE(bio_op(bio) == REQ_OP_ZONE_APPEND))
|
|
return NULL;
|
|
|
|
split = bio_alloc_clone(bio->bi_bdev, bio, gfp, bs);
|
|
if (!split)
|
|
return NULL;
|
|
|
|
split->bi_iter.bi_size = sectors << 9;
|
|
|
|
if (bio_integrity(split))
|
|
bio_integrity_trim(split);
|
|
|
|
bio_advance(bio, split->bi_iter.bi_size);
|
|
|
|
if (bio_flagged(bio, BIO_TRACE_COMPLETION))
|
|
bio_set_flag(split, BIO_TRACE_COMPLETION);
|
|
|
|
return split;
|
|
}
|
|
EXPORT_SYMBOL(bio_split);
|
|
|
|
/**
|
|
* bio_trim - trim a bio
|
|
* @bio: bio to trim
|
|
* @offset: number of sectors to trim from the front of @bio
|
|
* @size: size we want to trim @bio to, in sectors
|
|
*
|
|
* This function is typically used for bios that are cloned and submitted
|
|
* to the underlying device in parts.
|
|
*/
|
|
void bio_trim(struct bio *bio, sector_t offset, sector_t size)
|
|
{
|
|
if (WARN_ON_ONCE(offset > BIO_MAX_SECTORS || size > BIO_MAX_SECTORS ||
|
|
offset + size > bio_sectors(bio)))
|
|
return;
|
|
|
|
size <<= 9;
|
|
if (offset == 0 && size == bio->bi_iter.bi_size)
|
|
return;
|
|
|
|
bio_advance(bio, offset << 9);
|
|
bio->bi_iter.bi_size = size;
|
|
|
|
if (bio_integrity(bio))
|
|
bio_integrity_trim(bio);
|
|
}
|
|
EXPORT_SYMBOL_GPL(bio_trim);
|
|
|
|
/*
|
|
* create memory pools for biovec's in a bio_set.
|
|
* use the global biovec slabs created for general use.
|
|
*/
|
|
int biovec_init_pool(mempool_t *pool, int pool_entries)
|
|
{
|
|
struct biovec_slab *bp = bvec_slabs + ARRAY_SIZE(bvec_slabs) - 1;
|
|
|
|
return mempool_init_slab_pool(pool, pool_entries, bp->slab);
|
|
}
|
|
|
|
/*
|
|
* bioset_exit - exit a bioset initialized with bioset_init()
|
|
*
|
|
* May be called on a zeroed but uninitialized bioset (i.e. allocated with
|
|
* kzalloc()).
|
|
*/
|
|
void bioset_exit(struct bio_set *bs)
|
|
{
|
|
bio_alloc_cache_destroy(bs);
|
|
if (bs->rescue_workqueue)
|
|
destroy_workqueue(bs->rescue_workqueue);
|
|
bs->rescue_workqueue = NULL;
|
|
|
|
mempool_exit(&bs->bio_pool);
|
|
mempool_exit(&bs->bvec_pool);
|
|
|
|
bioset_integrity_free(bs);
|
|
if (bs->bio_slab)
|
|
bio_put_slab(bs);
|
|
bs->bio_slab = NULL;
|
|
}
|
|
EXPORT_SYMBOL(bioset_exit);
|
|
|
|
/**
|
|
* bioset_init - Initialize a bio_set
|
|
* @bs: pool to initialize
|
|
* @pool_size: Number of bio and bio_vecs to cache in the mempool
|
|
* @front_pad: Number of bytes to allocate in front of the returned bio
|
|
* @flags: Flags to modify behavior, currently %BIOSET_NEED_BVECS
|
|
* and %BIOSET_NEED_RESCUER
|
|
*
|
|
* Description:
|
|
* Set up a bio_set to be used with @bio_alloc_bioset. Allows the caller
|
|
* to ask for a number of bytes to be allocated in front of the bio.
|
|
* Front pad allocation is useful for embedding the bio inside
|
|
* another structure, to avoid allocating extra data to go with the bio.
|
|
* Note that the bio must be embedded at the END of that structure always,
|
|
* or things will break badly.
|
|
* If %BIOSET_NEED_BVECS is set in @flags, a separate pool will be allocated
|
|
* for allocating iovecs. This pool is not needed e.g. for bio_init_clone().
|
|
* If %BIOSET_NEED_RESCUER is set, a workqueue is created which can be used
|
|
* to dispatch queued requests when the mempool runs out of space.
|
|
*
|
|
*/
|
|
int bioset_init(struct bio_set *bs,
|
|
unsigned int pool_size,
|
|
unsigned int front_pad,
|
|
int flags)
|
|
{
|
|
bs->front_pad = front_pad;
|
|
if (flags & BIOSET_NEED_BVECS)
|
|
bs->back_pad = BIO_INLINE_VECS * sizeof(struct bio_vec);
|
|
else
|
|
bs->back_pad = 0;
|
|
|
|
spin_lock_init(&bs->rescue_lock);
|
|
bio_list_init(&bs->rescue_list);
|
|
INIT_WORK(&bs->rescue_work, bio_alloc_rescue);
|
|
|
|
bs->bio_slab = bio_find_or_create_slab(bs);
|
|
if (!bs->bio_slab)
|
|
return -ENOMEM;
|
|
|
|
if (mempool_init_slab_pool(&bs->bio_pool, pool_size, bs->bio_slab))
|
|
goto bad;
|
|
|
|
if ((flags & BIOSET_NEED_BVECS) &&
|
|
biovec_init_pool(&bs->bvec_pool, pool_size))
|
|
goto bad;
|
|
|
|
if (flags & BIOSET_NEED_RESCUER) {
|
|
bs->rescue_workqueue = alloc_workqueue("bioset",
|
|
WQ_MEM_RECLAIM, 0);
|
|
if (!bs->rescue_workqueue)
|
|
goto bad;
|
|
}
|
|
if (flags & BIOSET_PERCPU_CACHE) {
|
|
bs->cache = alloc_percpu(struct bio_alloc_cache);
|
|
if (!bs->cache)
|
|
goto bad;
|
|
cpuhp_state_add_instance_nocalls(CPUHP_BIO_DEAD, &bs->cpuhp_dead);
|
|
}
|
|
|
|
return 0;
|
|
bad:
|
|
bioset_exit(bs);
|
|
return -ENOMEM;
|
|
}
|
|
EXPORT_SYMBOL(bioset_init);
|
|
|
|
static int __init init_bio(void)
|
|
{
|
|
int i;
|
|
|
|
BUILD_BUG_ON(BIO_FLAG_LAST > 8 * sizeof_field(struct bio, bi_flags));
|
|
|
|
bio_integrity_init();
|
|
|
|
for (i = 0; i < ARRAY_SIZE(bvec_slabs); i++) {
|
|
struct biovec_slab *bvs = bvec_slabs + i;
|
|
|
|
bvs->slab = kmem_cache_create(bvs->name,
|
|
bvs->nr_vecs * sizeof(struct bio_vec), 0,
|
|
SLAB_HWCACHE_ALIGN | SLAB_PANIC, NULL);
|
|
}
|
|
|
|
cpuhp_setup_state_multi(CPUHP_BIO_DEAD, "block/bio:dead", NULL,
|
|
bio_cpu_dead);
|
|
|
|
if (bioset_init(&fs_bio_set, BIO_POOL_SIZE, 0,
|
|
BIOSET_NEED_BVECS | BIOSET_PERCPU_CACHE))
|
|
panic("bio: can't allocate bios\n");
|
|
|
|
if (bioset_integrity_create(&fs_bio_set, BIO_POOL_SIZE))
|
|
panic("bio: can't create integrity pool\n");
|
|
|
|
return 0;
|
|
}
|
|
subsys_initcall(init_bio);
|