fs/iomap/bio.c

Source file repositories/reference/linux-study-clean/fs/iomap/bio.c

File Facts

System
Linux kernel
Corpus path
fs/iomap/bio.c
Extension
.c
Size
4977 bytes
Lines
180
Domain
Core OS
Bucket
VFS And Filesystem Core
Inferred role
Core OS: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) 2010 Red Hat, Inc.
 * Copyright (C) 2016-2023 Christoph Hellwig.
 */
#include <linux/bio-integrity.h>
#include <linux/iomap.h>
#include <linux/pagemap.h>
#include "internal.h"
#include "trace.h"

static DEFINE_SPINLOCK(failed_read_lock);
static struct bio_list failed_read_list = BIO_EMPTY_LIST;

static u32 __iomap_read_end_io(struct bio *bio, int error)
{
	struct folio_iter fi;
	u32 folio_count = 0;

	bio_for_each_folio_all(fi, bio) {
		iomap_finish_folio_read(fi.folio, fi.offset, fi.length, error);
		folio_count++;
	}
	if (bio_integrity(bio))
		fs_bio_integrity_free(bio);
	bio_put(bio);
	return folio_count;
}

static void
iomap_fail_reads(
	struct work_struct	*work)
{
	struct bio		*bio;
	struct bio_list		tmp = BIO_EMPTY_LIST;
	unsigned long		flags;

	spin_lock_irqsave(&failed_read_lock, flags);
	bio_list_merge_init(&tmp, &failed_read_list);
	spin_unlock_irqrestore(&failed_read_lock, flags);

	while ((bio = bio_list_pop(&tmp)) != NULL) {
		__iomap_read_end_io(bio, blk_status_to_errno(bio->bi_status));
		cond_resched();
	}
}

static DECLARE_WORK(failed_read_work, iomap_fail_reads);

static void iomap_fail_buffered_read(struct bio *bio)
{
	unsigned long flags;

	/*
	 * Bounce I/O errors to a workqueue to avoid nested i_lock acquisitions
	 * in the fserror code.  The caller no longer owns the bio reference
	 * after the spinlock drops.
	 */
	spin_lock_irqsave(&failed_read_lock, flags);
	if (bio_list_empty(&failed_read_list))
		WARN_ON_ONCE(!schedule_work(&failed_read_work));
	bio_list_add(&failed_read_list, bio);
	spin_unlock_irqrestore(&failed_read_lock, flags);
}

static void iomap_read_end_io(struct bio *bio)
{
	if (bio->bi_status) {
		iomap_fail_buffered_read(bio);
		return;
	}

	__iomap_read_end_io(bio, 0);
}

u32 iomap_finish_ioend_buffered_read(struct iomap_ioend *ioend)
{
	return __iomap_read_end_io(&ioend->io_bio, ioend->io_error);
}

static void iomap_bio_submit_read(const struct iomap_iter *iter,
		struct iomap_read_folio_ctx *ctx)
{
	struct bio *bio = ctx->read_ctx;

	if (iter->iomap.flags & IOMAP_F_INTEGRITY)
		fs_bio_integrity_alloc(bio);
	submit_bio(bio);
}

Annotation

Implementation Notes