.. kernel-doc:: block/genhd.c
:export:
+.. kernel-doc:: block/bdev.c
+ :export:
+
Char devices
============
.. kernel-doc:: fs/fs-writeback.c
:export:
-.. kernel-doc:: fs/block_dev.c
- :export:
-
.. kernel-doc:: fs/anon_inodes.c
:export:
T: git git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git
F: block/
F: drivers/block/
-F: fs/block_dev.c
F: include/linux/blk*
F: kernel/trace/blktrace.c
F: lib/sbitmap.c
NVM EXPRESS TARGET DRIVER
M: Christoph Hellwig <hch@lst.de>
M: Sagi Grimberg <sagi@grimberg.me>
-M: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
+M: Chaitanya Kulkarni <kch@nvidia.com>
L: linux-nvme@lists.infradead.org
S: Supported
W: http://git.infradead.org/nvme.git
# Makefile for the kernel block layer
#
-obj-$(CONFIG_BLOCK) := bio.o elevator.o blk-core.o blk-sysfs.o \
+obj-$(CONFIG_BLOCK) := bdev.o fops.o bio.o elevator.o blk-core.o blk-sysfs.o \
blk-flush.o blk-settings.o blk-ioc.o blk-map.o \
blk-exec.o blk-merge.o blk-timeout.o \
blk-lib.o blk-mq.o blk-mq-tag.o blk-stat.o \
--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ * Copyright (C) 2001 Andrea Arcangeli <andrea@suse.de> SuSE
+ * Copyright (C) 2016 - 2020 Christoph Hellwig
+ */
+
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/kmod.h>
+#include <linux/major.h>
+#include <linux/device_cgroup.h>
+#include <linux/blkdev.h>
+#include <linux/backing-dev.h>
+#include <linux/module.h>
+#include <linux/blkpg.h>
+#include <linux/magic.h>
+#include <linux/buffer_head.h>
+#include <linux/swap.h>
+#include <linux/writeback.h>
+#include <linux/mount.h>
+#include <linux/pseudo_fs.h>
+#include <linux/uio.h>
+#include <linux/namei.h>
+#include <linux/cleancache.h>
+#include <linux/part_stat.h>
+#include <linux/uaccess.h>
+#include "../fs/internal.h"
+#include "blk.h"
+
+struct bdev_inode {
+ struct block_device bdev;
+ struct inode vfs_inode;
+};
+
+static inline struct bdev_inode *BDEV_I(struct inode *inode)
+{
+ return container_of(inode, struct bdev_inode, vfs_inode);
+}
+
+struct block_device *I_BDEV(struct inode *inode)
+{
+ return &BDEV_I(inode)->bdev;
+}
+EXPORT_SYMBOL(I_BDEV);
+
+static void bdev_write_inode(struct block_device *bdev)
+{
+ struct inode *inode = bdev->bd_inode;
+ int ret;
+
+ spin_lock(&inode->i_lock);
+ while (inode->i_state & I_DIRTY) {
+ spin_unlock(&inode->i_lock);
+ ret = write_inode_now(inode, true);
+ if (ret) {
+ char name[BDEVNAME_SIZE];
+ pr_warn_ratelimited("VFS: Dirty inode writeback failed "
+ "for block device %s (err=%d).\n",
+ bdevname(bdev, name), ret);
+ }
+ spin_lock(&inode->i_lock);
+ }
+ spin_unlock(&inode->i_lock);
+}
+
+/* Kill _all_ buffers and pagecache , dirty or not.. */
+static void kill_bdev(struct block_device *bdev)
+{
+ struct address_space *mapping = bdev->bd_inode->i_mapping;
+
+ if (mapping_empty(mapping))
+ return;
+
+ invalidate_bh_lrus();
+ truncate_inode_pages(mapping, 0);
+}
+
+/* Invalidate clean unused buffers and pagecache. */
+void invalidate_bdev(struct block_device *bdev)
+{
+ struct address_space *mapping = bdev->bd_inode->i_mapping;
+
+ if (mapping->nrpages) {
+ invalidate_bh_lrus();
+ lru_add_drain_all(); /* make sure all lru add caches are flushed */
+ invalidate_mapping_pages(mapping, 0, -1);
+ }
+ /* 99% of the time, we don't need to flush the cleancache on the bdev.
+ * But, for the strange corners, lets be cautious
+ */
+ cleancache_invalidate_inode(mapping);
+}
+EXPORT_SYMBOL(invalidate_bdev);
+
+/*
+ * Drop all buffers & page cache for given bdev range. This function bails
+ * with error if bdev has other exclusive owner (such as filesystem).
+ */
+int truncate_bdev_range(struct block_device *bdev, fmode_t mode,
+ loff_t lstart, loff_t lend)
+{
+ /*
+ * If we don't hold exclusive handle for the device, upgrade to it
+ * while we discard the buffer cache to avoid discarding buffers
+ * under live filesystem.
+ */
+ if (!(mode & FMODE_EXCL)) {
+ int err = bd_prepare_to_claim(bdev, truncate_bdev_range);
+ if (err)
+ goto invalidate;
+ }
+
+ truncate_inode_pages_range(bdev->bd_inode->i_mapping, lstart, lend);
+ if (!(mode & FMODE_EXCL))
+ bd_abort_claiming(bdev, truncate_bdev_range);
+ return 0;
+
+invalidate:
+ /*
+ * Someone else has handle exclusively open. Try invalidating instead.
+ * The 'end' argument is inclusive so the rounding is safe.
+ */
+ return invalidate_inode_pages2_range(bdev->bd_inode->i_mapping,
+ lstart >> PAGE_SHIFT,
+ lend >> PAGE_SHIFT);
+}
+
+static void set_init_blocksize(struct block_device *bdev)
+{
+ unsigned int bsize = bdev_logical_block_size(bdev);
+ loff_t size = i_size_read(bdev->bd_inode);
+
+ while (bsize < PAGE_SIZE) {
+ if (size & bsize)
+ break;
+ bsize <<= 1;
+ }
+ bdev->bd_inode->i_blkbits = blksize_bits(bsize);
+}
+
+int set_blocksize(struct block_device *bdev, int size)
+{
+ /* Size must be a power of two, and between 512 and PAGE_SIZE */
+ if (size > PAGE_SIZE || size < 512 || !is_power_of_2(size))
+ return -EINVAL;
+
+ /* Size cannot be smaller than the size supported by the device */
+ if (size < bdev_logical_block_size(bdev))
+ return -EINVAL;
+
+ /* Don't change the size if it is same as current */
+ if (bdev->bd_inode->i_blkbits != blksize_bits(size)) {
+ sync_blockdev(bdev);
+ bdev->bd_inode->i_blkbits = blksize_bits(size);
+ kill_bdev(bdev);
+ }
+ return 0;
+}
+
+EXPORT_SYMBOL(set_blocksize);
+
+int sb_set_blocksize(struct super_block *sb, int size)
+{
+ if (set_blocksize(sb->s_bdev, size))
+ return 0;
+ /* If we get here, we know size is power of two
+ * and it's value is between 512 and PAGE_SIZE */
+ sb->s_blocksize = size;
+ sb->s_blocksize_bits = blksize_bits(size);
+ return sb->s_blocksize;
+}
+
+EXPORT_SYMBOL(sb_set_blocksize);
+
+int sb_min_blocksize(struct super_block *sb, int size)
+{
+ int minsize = bdev_logical_block_size(sb->s_bdev);
+ if (size < minsize)
+ size = minsize;
+ return sb_set_blocksize(sb, size);
+}
+
+EXPORT_SYMBOL(sb_min_blocksize);
+
+int __sync_blockdev(struct block_device *bdev, int wait)
+{
+ if (!bdev)
+ return 0;
+ if (!wait)
+ return filemap_flush(bdev->bd_inode->i_mapping);
+ return filemap_write_and_wait(bdev->bd_inode->i_mapping);
+}
+
+/*
+ * Write out and wait upon all the dirty data associated with a block
+ * device via its mapping. Does not take the superblock lock.
+ */
+int sync_blockdev(struct block_device *bdev)
+{
+ return __sync_blockdev(bdev, 1);
+}
+EXPORT_SYMBOL(sync_blockdev);
+
+/*
+ * Write out and wait upon all dirty data associated with this
+ * device. Filesystem data as well as the underlying block
+ * device. Takes the superblock lock.
+ */
+int fsync_bdev(struct block_device *bdev)
+{
+ struct super_block *sb = get_super(bdev);
+ if (sb) {
+ int res = sync_filesystem(sb);
+ drop_super(sb);
+ return res;
+ }
+ return sync_blockdev(bdev);
+}
+EXPORT_SYMBOL(fsync_bdev);
+
+/**
+ * freeze_bdev -- lock a filesystem and force it into a consistent state
+ * @bdev: blockdevice to lock
+ *
+ * If a superblock is found on this device, we take the s_umount semaphore
+ * on it to make sure nobody unmounts until the snapshot creation is done.
+ * The reference counter (bd_fsfreeze_count) guarantees that only the last
+ * unfreeze process can unfreeze the frozen filesystem actually when multiple
+ * freeze requests arrive simultaneously. It counts up in freeze_bdev() and
+ * count down in thaw_bdev(). When it becomes 0, thaw_bdev() will unfreeze
+ * actually.
+ */
+int freeze_bdev(struct block_device *bdev)
+{
+ struct super_block *sb;
+ int error = 0;
+
+ mutex_lock(&bdev->bd_fsfreeze_mutex);
+ if (++bdev->bd_fsfreeze_count > 1)
+ goto done;
+
+ sb = get_active_super(bdev);
+ if (!sb)
+ goto sync;
+ if (sb->s_op->freeze_super)
+ error = sb->s_op->freeze_super(sb);
+ else
+ error = freeze_super(sb);
+ deactivate_super(sb);
+
+ if (error) {
+ bdev->bd_fsfreeze_count--;
+ goto done;
+ }
+ bdev->bd_fsfreeze_sb = sb;
+
+sync:
+ sync_blockdev(bdev);
+done:
+ mutex_unlock(&bdev->bd_fsfreeze_mutex);
+ return error;
+}
+EXPORT_SYMBOL(freeze_bdev);
+
+/**
+ * thaw_bdev -- unlock filesystem
+ * @bdev: blockdevice to unlock
+ *
+ * Unlocks the filesystem and marks it writeable again after freeze_bdev().
+ */
+int thaw_bdev(struct block_device *bdev)
+{
+ struct super_block *sb;
+ int error = -EINVAL;
+
+ mutex_lock(&bdev->bd_fsfreeze_mutex);
+ if (!bdev->bd_fsfreeze_count)
+ goto out;
+
+ error = 0;
+ if (--bdev->bd_fsfreeze_count > 0)
+ goto out;
+
+ sb = bdev->bd_fsfreeze_sb;
+ if (!sb)
+ goto out;
+
+ if (sb->s_op->thaw_super)
+ error = sb->s_op->thaw_super(sb);
+ else
+ error = thaw_super(sb);
+ if (error)
+ bdev->bd_fsfreeze_count++;
+ else
+ bdev->bd_fsfreeze_sb = NULL;
+out:
+ mutex_unlock(&bdev->bd_fsfreeze_mutex);
+ return error;
+}
+EXPORT_SYMBOL(thaw_bdev);
+
+/**
+ * bdev_read_page() - Start reading a page from a block device
+ * @bdev: The device to read the page from
+ * @sector: The offset on the device to read the page to (need not be aligned)
+ * @page: The page to read
+ *
+ * On entry, the page should be locked. It will be unlocked when the page
+ * has been read. If the block driver implements rw_page synchronously,
+ * that will be true on exit from this function, but it need not be.
+ *
+ * Errors returned by this function are usually "soft", eg out of memory, or
+ * queue full; callers should try a different route to read this page rather
+ * than propagate an error back up the stack.
+ *
+ * Return: negative errno if an error occurs, 0 if submission was successful.
+ */
+int bdev_read_page(struct block_device *bdev, sector_t sector,
+ struct page *page)
+{
+ const struct block_device_operations *ops = bdev->bd_disk->fops;
+ int result = -EOPNOTSUPP;
+
+ if (!ops->rw_page || bdev_get_integrity(bdev))
+ return result;
+
+ result = blk_queue_enter(bdev->bd_disk->queue, 0);
+ if (result)
+ return result;
+ result = ops->rw_page(bdev, sector + get_start_sect(bdev), page,
+ REQ_OP_READ);
+ blk_queue_exit(bdev->bd_disk->queue);
+ return result;
+}
+
+/**
+ * bdev_write_page() - Start writing a page to a block device
+ * @bdev: The device to write the page to
+ * @sector: The offset on the device to write the page to (need not be aligned)
+ * @page: The page to write
+ * @wbc: The writeback_control for the write
+ *
+ * On entry, the page should be locked and not currently under writeback.
+ * On exit, if the write started successfully, the page will be unlocked and
+ * under writeback. If the write failed already (eg the driver failed to
+ * queue the page to the device), the page will still be locked. If the
+ * caller is a ->writepage implementation, it will need to unlock the page.
+ *
+ * Errors returned by this function are usually "soft", eg out of memory, or
+ * queue full; callers should try a different route to write this page rather
+ * than propagate an error back up the stack.
+ *
+ * Return: negative errno if an error occurs, 0 if submission was successful.
+ */
+int bdev_write_page(struct block_device *bdev, sector_t sector,
+ struct page *page, struct writeback_control *wbc)
+{
+ int result;
+ const struct block_device_operations *ops = bdev->bd_disk->fops;
+
+ if (!ops->rw_page || bdev_get_integrity(bdev))
+ return -EOPNOTSUPP;
+ result = blk_queue_enter(bdev->bd_disk->queue, 0);
+ if (result)
+ return result;
+
+ set_page_writeback(page);
+ result = ops->rw_page(bdev, sector + get_start_sect(bdev), page,
+ REQ_OP_WRITE);
+ if (result) {
+ end_page_writeback(page);
+ } else {
+ clean_page_buffers(page);
+ unlock_page(page);
+ }
+ blk_queue_exit(bdev->bd_disk->queue);
+ return result;
+}
+
+/*
+ * pseudo-fs
+ */
+
+static __cacheline_aligned_in_smp DEFINE_SPINLOCK(bdev_lock);
+static struct kmem_cache * bdev_cachep __read_mostly;
+
+static struct inode *bdev_alloc_inode(struct super_block *sb)
+{
+ struct bdev_inode *ei = kmem_cache_alloc(bdev_cachep, GFP_KERNEL);
+
+ if (!ei)
+ return NULL;
+ memset(&ei->bdev, 0, sizeof(ei->bdev));
+ return &ei->vfs_inode;
+}
+
+static void bdev_free_inode(struct inode *inode)
+{
+ struct block_device *bdev = I_BDEV(inode);
+
+ free_percpu(bdev->bd_stats);
+ kfree(bdev->bd_meta_info);
+
+ if (!bdev_is_partition(bdev)) {
+ if (bdev->bd_disk && bdev->bd_disk->bdi)
+ bdi_put(bdev->bd_disk->bdi);
+ kfree(bdev->bd_disk);
+ }
+
+ if (MAJOR(bdev->bd_dev) == BLOCK_EXT_MAJOR)
+ blk_free_ext_minor(MINOR(bdev->bd_dev));
+
+ kmem_cache_free(bdev_cachep, BDEV_I(inode));
+}
+
+static void init_once(void *data)
+{
+ struct bdev_inode *ei = data;
+
+ inode_init_once(&ei->vfs_inode);
+}
+
+static void bdev_evict_inode(struct inode *inode)
+{
+ truncate_inode_pages_final(&inode->i_data);
+ invalidate_inode_buffers(inode); /* is it needed here? */
+ clear_inode(inode);
+}
+
+static const struct super_operations bdev_sops = {
+ .statfs = simple_statfs,
+ .alloc_inode = bdev_alloc_inode,
+ .free_inode = bdev_free_inode,
+ .drop_inode = generic_delete_inode,
+ .evict_inode = bdev_evict_inode,
+};
+
+static int bd_init_fs_context(struct fs_context *fc)
+{
+ struct pseudo_fs_context *ctx = init_pseudo(fc, BDEVFS_MAGIC);
+ if (!ctx)
+ return -ENOMEM;
+ fc->s_iflags |= SB_I_CGROUPWB;
+ ctx->ops = &bdev_sops;
+ return 0;
+}
+
+static struct file_system_type bd_type = {
+ .name = "bdev",
+ .init_fs_context = bd_init_fs_context,
+ .kill_sb = kill_anon_super,
+};
+
+struct super_block *blockdev_superblock __read_mostly;
+EXPORT_SYMBOL_GPL(blockdev_superblock);
+
+void __init bdev_cache_init(void)
+{
+ int err;
+ static struct vfsmount *bd_mnt;
+
+ bdev_cachep = kmem_cache_create("bdev_cache", sizeof(struct bdev_inode),
+ 0, (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|
+ SLAB_MEM_SPREAD|SLAB_ACCOUNT|SLAB_PANIC),
+ init_once);
+ err = register_filesystem(&bd_type);
+ if (err)
+ panic("Cannot register bdev pseudo-fs");
+ bd_mnt = kern_mount(&bd_type);
+ if (IS_ERR(bd_mnt))
+ panic("Cannot create bdev pseudo-fs");
+ blockdev_superblock = bd_mnt->mnt_sb; /* For writeback */
+}
+
+struct block_device *bdev_alloc(struct gendisk *disk, u8 partno)
+{
+ struct block_device *bdev;
+ struct inode *inode;
+
+ inode = new_inode(blockdev_superblock);
+ if (!inode)
+ return NULL;
+ inode->i_mode = S_IFBLK;
+ inode->i_rdev = 0;
+ inode->i_data.a_ops = &def_blk_aops;
+ mapping_set_gfp_mask(&inode->i_data, GFP_USER);
+
+ bdev = I_BDEV(inode);
+ mutex_init(&bdev->bd_fsfreeze_mutex);
+ spin_lock_init(&bdev->bd_size_lock);
+ bdev->bd_disk = disk;
+ bdev->bd_partno = partno;
+ bdev->bd_inode = inode;
+ bdev->bd_stats = alloc_percpu(struct disk_stats);
+ if (!bdev->bd_stats) {
+ iput(inode);
+ return NULL;
+ }
+ return bdev;
+}
+
+void bdev_add(struct block_device *bdev, dev_t dev)
+{
+ bdev->bd_dev = dev;
+ bdev->bd_inode->i_rdev = dev;
+ bdev->bd_inode->i_ino = dev;
+ insert_inode_hash(bdev->bd_inode);
+}
+
+long nr_blockdev_pages(void)
+{
+ struct inode *inode;
+ long ret = 0;
+
+ spin_lock(&blockdev_superblock->s_inode_list_lock);
+ list_for_each_entry(inode, &blockdev_superblock->s_inodes, i_sb_list)
+ ret += inode->i_mapping->nrpages;
+ spin_unlock(&blockdev_superblock->s_inode_list_lock);
+
+ return ret;
+}
+
+/**
+ * bd_may_claim - test whether a block device can be claimed
+ * @bdev: block device of interest
+ * @whole: whole block device containing @bdev, may equal @bdev
+ * @holder: holder trying to claim @bdev
+ *
+ * Test whether @bdev can be claimed by @holder.
+ *
+ * CONTEXT:
+ * spin_lock(&bdev_lock).
+ *
+ * RETURNS:
+ * %true if @bdev can be claimed, %false otherwise.
+ */
+static bool bd_may_claim(struct block_device *bdev, struct block_device *whole,
+ void *holder)
+{
+ if (bdev->bd_holder == holder)
+ return true; /* already a holder */
+ else if (bdev->bd_holder != NULL)
+ return false; /* held by someone else */
+ else if (whole == bdev)
+ return true; /* is a whole device which isn't held */
+
+ else if (whole->bd_holder == bd_may_claim)
+ return true; /* is a partition of a device that is being partitioned */
+ else if (whole->bd_holder != NULL)
+ return false; /* is a partition of a held device */
+ else
+ return true; /* is a partition of an un-held device */
+}
+
+/**
+ * bd_prepare_to_claim - claim a block device
+ * @bdev: block device of interest
+ * @holder: holder trying to claim @bdev
+ *
+ * Claim @bdev. This function fails if @bdev is already claimed by another
+ * holder and waits if another claiming is in progress. return, the caller
+ * has ownership of bd_claiming and bd_holder[s].
+ *
+ * RETURNS:
+ * 0 if @bdev can be claimed, -EBUSY otherwise.
+ */
+int bd_prepare_to_claim(struct block_device *bdev, void *holder)
+{
+ struct block_device *whole = bdev_whole(bdev);
+
+ if (WARN_ON_ONCE(!holder))
+ return -EINVAL;
+retry:
+ spin_lock(&bdev_lock);
+ /* if someone else claimed, fail */
+ if (!bd_may_claim(bdev, whole, holder)) {
+ spin_unlock(&bdev_lock);
+ return -EBUSY;
+ }
+
+ /* if claiming is already in progress, wait for it to finish */
+ if (whole->bd_claiming) {
+ wait_queue_head_t *wq = bit_waitqueue(&whole->bd_claiming, 0);
+ DEFINE_WAIT(wait);
+
+ prepare_to_wait(wq, &wait, TASK_UNINTERRUPTIBLE);
+ spin_unlock(&bdev_lock);
+ schedule();
+ finish_wait(wq, &wait);
+ goto retry;
+ }
+
+ /* yay, all mine */
+ whole->bd_claiming = holder;
+ spin_unlock(&bdev_lock);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(bd_prepare_to_claim); /* only for the loop driver */
+
+static void bd_clear_claiming(struct block_device *whole, void *holder)
+{
+ lockdep_assert_held(&bdev_lock);
+ /* tell others that we're done */
+ BUG_ON(whole->bd_claiming != holder);
+ whole->bd_claiming = NULL;
+ wake_up_bit(&whole->bd_claiming, 0);
+}
+
+/**
+ * bd_finish_claiming - finish claiming of a block device
+ * @bdev: block device of interest
+ * @holder: holder that has claimed @bdev
+ *
+ * Finish exclusive open of a block device. Mark the device as exlusively
+ * open by the holder and wake up all waiters for exclusive open to finish.
+ */
+static void bd_finish_claiming(struct block_device *bdev, void *holder)
+{
+ struct block_device *whole = bdev_whole(bdev);
+
+ spin_lock(&bdev_lock);
+ BUG_ON(!bd_may_claim(bdev, whole, holder));
+ /*
+ * Note that for a whole device bd_holders will be incremented twice,
+ * and bd_holder will be set to bd_may_claim before being set to holder
+ */
+ whole->bd_holders++;
+ whole->bd_holder = bd_may_claim;
+ bdev->bd_holders++;
+ bdev->bd_holder = holder;
+ bd_clear_claiming(whole, holder);
+ spin_unlock(&bdev_lock);
+}
+
+/**
+ * bd_abort_claiming - abort claiming of a block device
+ * @bdev: block device of interest
+ * @holder: holder that has claimed @bdev
+ *
+ * Abort claiming of a block device when the exclusive open failed. This can be
+ * also used when exclusive open is not actually desired and we just needed
+ * to block other exclusive openers for a while.
+ */
+void bd_abort_claiming(struct block_device *bdev, void *holder)
+{
+ spin_lock(&bdev_lock);
+ bd_clear_claiming(bdev_whole(bdev), holder);
+ spin_unlock(&bdev_lock);
+}
+EXPORT_SYMBOL(bd_abort_claiming);
+
+static void blkdev_flush_mapping(struct block_device *bdev)
+{
+ WARN_ON_ONCE(bdev->bd_holders);
+ sync_blockdev(bdev);
+ kill_bdev(bdev);
+ bdev_write_inode(bdev);
+}
+
+static int blkdev_get_whole(struct block_device *bdev, fmode_t mode)
+{
+ struct gendisk *disk = bdev->bd_disk;
+ int ret = 0;
+
+ if (disk->fops->open) {
+ ret = disk->fops->open(bdev, mode);
+ if (ret) {
+ /* avoid ghost partitions on a removed medium */
+ if (ret == -ENOMEDIUM &&
+ test_bit(GD_NEED_PART_SCAN, &disk->state))
+ bdev_disk_changed(disk, true);
+ return ret;
+ }
+ }
+
+ if (!bdev->bd_openers)
+ set_init_blocksize(bdev);
+ if (test_bit(GD_NEED_PART_SCAN, &disk->state))
+ bdev_disk_changed(disk, false);
+ bdev->bd_openers++;
+ return 0;;
+}
+
+static void blkdev_put_whole(struct block_device *bdev, fmode_t mode)
+{
+ if (!--bdev->bd_openers)
+ blkdev_flush_mapping(bdev);
+ if (bdev->bd_disk->fops->release)
+ bdev->bd_disk->fops->release(bdev->bd_disk, mode);
+}
+
+static int blkdev_get_part(struct block_device *part, fmode_t mode)
+{
+ struct gendisk *disk = part->bd_disk;
+ int ret;
+
+ if (part->bd_openers)
+ goto done;
+
+ ret = blkdev_get_whole(bdev_whole(part), mode);
+ if (ret)
+ return ret;
+
+ ret = -ENXIO;
+ if (!bdev_nr_sectors(part))
+ goto out_blkdev_put;
+
+ disk->open_partitions++;
+ set_init_blocksize(part);
+done:
+ part->bd_openers++;
+ return 0;
+
+out_blkdev_put:
+ blkdev_put_whole(bdev_whole(part), mode);
+ return ret;
+}
+
+static void blkdev_put_part(struct block_device *part, fmode_t mode)
+{
+ struct block_device *whole = bdev_whole(part);
+
+ if (--part->bd_openers)
+ return;
+ blkdev_flush_mapping(part);
+ whole->bd_disk->open_partitions--;
+ blkdev_put_whole(whole, mode);
+}
+
+struct block_device *blkdev_get_no_open(dev_t dev)
+{
+ struct block_device *bdev;
+ struct inode *inode;
+
+ inode = ilookup(blockdev_superblock, dev);
+ if (!inode) {
+ blk_request_module(dev);
+ inode = ilookup(blockdev_superblock, dev);
+ if (!inode)
+ return NULL;
+ }
+
+ /* switch from the inode reference to a device mode one: */
+ bdev = &BDEV_I(inode)->bdev;
+ if (!kobject_get_unless_zero(&bdev->bd_device.kobj))
+ bdev = NULL;
+ iput(inode);
+
+ if (!bdev)
+ return NULL;
+ if ((bdev->bd_disk->flags & GENHD_FL_HIDDEN) ||
+ !try_module_get(bdev->bd_disk->fops->owner)) {
+ put_device(&bdev->bd_device);
+ return NULL;
+ }
+
+ return bdev;
+}
+
+void blkdev_put_no_open(struct block_device *bdev)
+{
+ module_put(bdev->bd_disk->fops->owner);
+ put_device(&bdev->bd_device);
+}
+
+/**
+ * blkdev_get_by_dev - open a block device by device number
+ * @dev: device number of block device to open
+ * @mode: FMODE_* mask
+ * @holder: exclusive holder identifier
+ *
+ * Open the block device described by device number @dev. If @mode includes
+ * %FMODE_EXCL, the block device is opened with exclusive access. Specifying
+ * %FMODE_EXCL with a %NULL @holder is invalid. Exclusive opens may nest for
+ * the same @holder.
+ *
+ * Use this interface ONLY if you really do not have anything better - i.e. when
+ * you are behind a truly sucky interface and all you are given is a device
+ * number. Everything else should use blkdev_get_by_path().
+ *
+ * CONTEXT:
+ * Might sleep.
+ *
+ * RETURNS:
+ * Reference to the block_device on success, ERR_PTR(-errno) on failure.
+ */
+struct block_device *blkdev_get_by_dev(dev_t dev, fmode_t mode, void *holder)
+{
+ bool unblock_events = true;
+ struct block_device *bdev;
+ struct gendisk *disk;
+ int ret;
+
+ ret = devcgroup_check_permission(DEVCG_DEV_BLOCK,
+ MAJOR(dev), MINOR(dev),
+ ((mode & FMODE_READ) ? DEVCG_ACC_READ : 0) |
+ ((mode & FMODE_WRITE) ? DEVCG_ACC_WRITE : 0));
+ if (ret)
+ return ERR_PTR(ret);
+
+ bdev = blkdev_get_no_open(dev);
+ if (!bdev)
+ return ERR_PTR(-ENXIO);
+ disk = bdev->bd_disk;
+
+ if (mode & FMODE_EXCL) {
+ ret = bd_prepare_to_claim(bdev, holder);
+ if (ret)
+ goto put_blkdev;
+ }
+
+ disk_block_events(disk);
+
+ mutex_lock(&disk->open_mutex);
+ ret = -ENXIO;
+ if (!disk_live(disk))
+ goto abort_claiming;
+ if (bdev_is_partition(bdev))
+ ret = blkdev_get_part(bdev, mode);
+ else
+ ret = blkdev_get_whole(bdev, mode);
+ if (ret)
+ goto abort_claiming;
+ if (mode & FMODE_EXCL) {
+ bd_finish_claiming(bdev, holder);
+
+ /*
+ * Block event polling for write claims if requested. Any write
+ * holder makes the write_holder state stick until all are
+ * released. This is good enough and tracking individual
+ * writeable reference is too fragile given the way @mode is
+ * used in blkdev_get/put().
+ */
+ if ((mode & FMODE_WRITE) && !bdev->bd_write_holder &&
+ (disk->flags & GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE)) {
+ bdev->bd_write_holder = true;
+ unblock_events = false;
+ }
+ }
+ mutex_unlock(&disk->open_mutex);
+
+ if (unblock_events)
+ disk_unblock_events(disk);
+ return bdev;
+
+abort_claiming:
+ if (mode & FMODE_EXCL)
+ bd_abort_claiming(bdev, holder);
+ mutex_unlock(&disk->open_mutex);
+ disk_unblock_events(disk);
+put_blkdev:
+ blkdev_put_no_open(bdev);
+ return ERR_PTR(ret);
+}
+EXPORT_SYMBOL(blkdev_get_by_dev);
+
+/**
+ * blkdev_get_by_path - open a block device by name
+ * @path: path to the block device to open
+ * @mode: FMODE_* mask
+ * @holder: exclusive holder identifier
+ *
+ * Open the block device described by the device file at @path. If @mode
+ * includes %FMODE_EXCL, the block device is opened with exclusive access.
+ * Specifying %FMODE_EXCL with a %NULL @holder is invalid. Exclusive opens may
+ * nest for the same @holder.
+ *
+ * CONTEXT:
+ * Might sleep.
+ *
+ * RETURNS:
+ * Reference to the block_device on success, ERR_PTR(-errno) on failure.
+ */
+struct block_device *blkdev_get_by_path(const char *path, fmode_t mode,
+ void *holder)
+{
+ struct block_device *bdev;
+ dev_t dev;
+ int error;
+
+ error = lookup_bdev(path, &dev);
+ if (error)
+ return ERR_PTR(error);
+
+ bdev = blkdev_get_by_dev(dev, mode, holder);
+ if (!IS_ERR(bdev) && (mode & FMODE_WRITE) && bdev_read_only(bdev)) {
+ blkdev_put(bdev, mode);
+ return ERR_PTR(-EACCES);
+ }
+
+ return bdev;
+}
+EXPORT_SYMBOL(blkdev_get_by_path);
+
+void blkdev_put(struct block_device *bdev, fmode_t mode)
+{
+ struct gendisk *disk = bdev->bd_disk;
+
+ /*
+ * Sync early if it looks like we're the last one. If someone else
+ * opens the block device between now and the decrement of bd_openers
+ * then we did a sync that we didn't need to, but that's not the end
+ * of the world and we want to avoid long (could be several minute)
+ * syncs while holding the mutex.
+ */
+ if (bdev->bd_openers == 1)
+ sync_blockdev(bdev);
+
+ mutex_lock(&disk->open_mutex);
+ if (mode & FMODE_EXCL) {
+ struct block_device *whole = bdev_whole(bdev);
+ bool bdev_free;
+
+ /*
+ * Release a claim on the device. The holder fields
+ * are protected with bdev_lock. open_mutex is to
+ * synchronize disk_holder unlinking.
+ */
+ spin_lock(&bdev_lock);
+
+ WARN_ON_ONCE(--bdev->bd_holders < 0);
+ WARN_ON_ONCE(--whole->bd_holders < 0);
+
+ if ((bdev_free = !bdev->bd_holders))
+ bdev->bd_holder = NULL;
+ if (!whole->bd_holders)
+ whole->bd_holder = NULL;
+
+ spin_unlock(&bdev_lock);
+
+ /*
+ * If this was the last claim, remove holder link and
+ * unblock evpoll if it was a write holder.
+ */
+ if (bdev_free && bdev->bd_write_holder) {
+ disk_unblock_events(disk);
+ bdev->bd_write_holder = false;
+ }
+ }
+
+ /*
+ * Trigger event checking and tell drivers to flush MEDIA_CHANGE
+ * event. This is to ensure detection of media removal commanded
+ * from userland - e.g. eject(1).
+ */
+ disk_flush_events(disk, DISK_EVENT_MEDIA_CHANGE);
+
+ if (bdev_is_partition(bdev))
+ blkdev_put_part(bdev, mode);
+ else
+ blkdev_put_whole(bdev, mode);
+ mutex_unlock(&disk->open_mutex);
+
+ blkdev_put_no_open(bdev);
+}
+EXPORT_SYMBOL(blkdev_put);
+
+/**
+ * lookup_bdev - lookup a struct block_device by name
+ * @pathname: special file representing the block device
+ * @dev: return value of the block device's dev_t
+ *
+ * Get a reference to the blockdevice at @pathname in the current
+ * namespace if possible and return it. Return ERR_PTR(error)
+ * otherwise.
+ */
+int lookup_bdev(const char *pathname, dev_t *dev)
+{
+ struct inode *inode;
+ struct path path;
+ int error;
+
+ if (!pathname || !*pathname)
+ return -EINVAL;
+
+ error = kern_path(pathname, LOOKUP_FOLLOW, &path);
+ if (error)
+ return error;
+
+ inode = d_backing_inode(path.dentry);
+ error = -ENOTBLK;
+ if (!S_ISBLK(inode->i_mode))
+ goto out_path_put;
+ error = -EACCES;
+ if (!may_open_dev(&path))
+ goto out_path_put;
+
+ *dev = inode->i_rdev;
+ error = 0;
+out_path_put:
+ path_put(&path);
+ return error;
+}
+EXPORT_SYMBOL(lookup_bdev);
+
+int __invalidate_device(struct block_device *bdev, bool kill_dirty)
+{
+ struct super_block *sb = get_super(bdev);
+ int res = 0;
+
+ if (sb) {
+ /*
+ * no need to lock the super, get_super holds the
+ * read mutex so the filesystem cannot go away
+ * under us (->put_super runs with the write lock
+ * hold).
+ */
+ shrink_dcache_sb(sb);
+ res = invalidate_inodes(sb, kill_dirty);
+ drop_super(sb);
+ }
+ invalidate_bdev(bdev);
+ return res;
+}
+EXPORT_SYMBOL(__invalidate_device);
+
+void iterate_bdevs(void (*func)(struct block_device *, void *), void *arg)
+{
+ struct inode *inode, *old_inode = NULL;
+
+ spin_lock(&blockdev_superblock->s_inode_list_lock);
+ list_for_each_entry(inode, &blockdev_superblock->s_inodes, i_sb_list) {
+ struct address_space *mapping = inode->i_mapping;
+ struct block_device *bdev;
+
+ spin_lock(&inode->i_lock);
+ if (inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW) ||
+ mapping->nrpages == 0) {
+ spin_unlock(&inode->i_lock);
+ continue;
+ }
+ __iget(inode);
+ spin_unlock(&inode->i_lock);
+ spin_unlock(&blockdev_superblock->s_inode_list_lock);
+ /*
+ * We hold a reference to 'inode' so it couldn't have been
+ * removed from s_inodes list while we dropped the
+ * s_inode_list_lock We cannot iput the inode now as we can
+ * be holding the last reference and we cannot iput it under
+ * s_inode_list_lock. So we keep the reference and iput it
+ * later.
+ */
+ iput(old_inode);
+ old_inode = inode;
+ bdev = I_BDEV(inode);
+
+ mutex_lock(&bdev->bd_disk->open_mutex);
+ if (bdev->bd_openers)
+ func(bdev, arg);
+ mutex_unlock(&bdev->bd_disk->open_mutex);
+
+ spin_lock(&blockdev_superblock->s_inode_list_lock);
+ }
+ spin_unlock(&blockdev_superblock->s_inode_list_lock);
+ iput(old_inode);
+}
}
}
+/*
+ * Allow 4x BLK_MAX_REQUEST_COUNT requests on plug queue for multiple
+ * queues. This is important for md arrays to benefit from merging
+ * requests.
+ */
+static inline unsigned short blk_plug_max_rq_count(struct blk_plug *plug)
+{
+ if (plug->multiple_queues)
+ return BLK_MAX_REQUEST_COUNT * 4;
+ return BLK_MAX_REQUEST_COUNT;
+}
+
/**
* blk_mq_submit_bio - Create and send a request to block device.
* @bio: Bio pointer.
else
last = list_entry_rq(plug->mq_list.prev);
- if (request_count >= BLK_MAX_REQUEST_COUNT || (last &&
+ if (request_count >= blk_plug_max_rq_count(plug) || (last &&
blk_rq_bytes(last) >= BLK_PLUG_FLUSH_SIZE)) {
blk_flush_plug_list(plug, false);
trace_block_plug(q);
void blk_throtl_exit(struct request_queue *q)
{
BUG_ON(!q->td);
+ del_timer_sync(&q->td->service_queue.pending_timer);
throtl_shutdown_wq(q);
blkcg_deactivate_policy(q, &blkcg_policy_throtl);
free_percpu(q->td->latency_buckets[READ]);
bio->bi_opf &= ~REQ_HIPRI;
}
+extern const struct address_space_operations def_blk_aops;
+
#endif /* BLK_INTERNAL_H */
--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ * Copyright (C) 2001 Andrea Arcangeli <andrea@suse.de> SuSE
+ * Copyright (C) 2016 - 2020 Christoph Hellwig
+ */
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/blkdev.h>
+#include <linux/buffer_head.h>
+#include <linux/mpage.h>
+#include <linux/uio.h>
+#include <linux/namei.h>
+#include <linux/task_io_accounting_ops.h>
+#include <linux/falloc.h>
+#include <linux/suspend.h>
+#include "blk.h"
+
+static struct inode *bdev_file_inode(struct file *file)
+{
+ return file->f_mapping->host;
+}
+
+static int blkdev_get_block(struct inode *inode, sector_t iblock,
+ struct buffer_head *bh, int create)
+{
+ bh->b_bdev = I_BDEV(inode);
+ bh->b_blocknr = iblock;
+ set_buffer_mapped(bh);
+ return 0;
+}
+
+static unsigned int dio_bio_write_op(struct kiocb *iocb)
+{
+ unsigned int op = REQ_OP_WRITE | REQ_SYNC | REQ_IDLE;
+
+ /* avoid the need for a I/O completion work item */
+ if (iocb->ki_flags & IOCB_DSYNC)
+ op |= REQ_FUA;
+ return op;
+}
+
+#define DIO_INLINE_BIO_VECS 4
+
+static void blkdev_bio_end_io_simple(struct bio *bio)
+{
+ struct task_struct *waiter = bio->bi_private;
+
+ WRITE_ONCE(bio->bi_private, NULL);
+ blk_wake_io_task(waiter);
+}
+
+static ssize_t __blkdev_direct_IO_simple(struct kiocb *iocb,
+ struct iov_iter *iter, unsigned int nr_pages)
+{
+ struct file *file = iocb->ki_filp;
+ struct block_device *bdev = I_BDEV(bdev_file_inode(file));
+ struct bio_vec inline_vecs[DIO_INLINE_BIO_VECS], *vecs;
+ loff_t pos = iocb->ki_pos;
+ bool should_dirty = false;
+ struct bio bio;
+ ssize_t ret;
+ blk_qc_t qc;
+
+ if ((pos | iov_iter_alignment(iter)) &
+ (bdev_logical_block_size(bdev) - 1))
+ return -EINVAL;
+
+ if (nr_pages <= DIO_INLINE_BIO_VECS)
+ vecs = inline_vecs;
+ else {
+ vecs = kmalloc_array(nr_pages, sizeof(struct bio_vec),
+ GFP_KERNEL);
+ if (!vecs)
+ return -ENOMEM;
+ }
+
+ bio_init(&bio, vecs, nr_pages);
+ bio_set_dev(&bio, bdev);
+ bio.bi_iter.bi_sector = pos >> 9;
+ bio.bi_write_hint = iocb->ki_hint;
+ bio.bi_private = current;
+ bio.bi_end_io = blkdev_bio_end_io_simple;
+ bio.bi_ioprio = iocb->ki_ioprio;
+
+ ret = bio_iov_iter_get_pages(&bio, iter);
+ if (unlikely(ret))
+ goto out;
+ ret = bio.bi_iter.bi_size;
+
+ if (iov_iter_rw(iter) == READ) {
+ bio.bi_opf = REQ_OP_READ;
+ if (iter_is_iovec(iter))
+ should_dirty = true;
+ } else {
+ bio.bi_opf = dio_bio_write_op(iocb);
+ task_io_account_write(ret);
+ }
+ if (iocb->ki_flags & IOCB_NOWAIT)
+ bio.bi_opf |= REQ_NOWAIT;
+ if (iocb->ki_flags & IOCB_HIPRI)
+ bio_set_polled(&bio, iocb);
+
+ qc = submit_bio(&bio);
+ for (;;) {
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ if (!READ_ONCE(bio.bi_private))
+ break;
+ if (!(iocb->ki_flags & IOCB_HIPRI) ||
+ !blk_poll(bdev_get_queue(bdev), qc, true))
+ blk_io_schedule();
+ }
+ __set_current_state(TASK_RUNNING);
+
+ bio_release_pages(&bio, should_dirty);
+ if (unlikely(bio.bi_status))
+ ret = blk_status_to_errno(bio.bi_status);
+
+out:
+ if (vecs != inline_vecs)
+ kfree(vecs);
+
+ bio_uninit(&bio);
+
+ return ret;
+}
+
+struct blkdev_dio {
+ union {
+ struct kiocb *iocb;
+ struct task_struct *waiter;
+ };
+ size_t size;
+ atomic_t ref;
+ bool multi_bio : 1;
+ bool should_dirty : 1;
+ bool is_sync : 1;
+ struct bio bio;
+};
+
+static struct bio_set blkdev_dio_pool;
+
+static int blkdev_iopoll(struct kiocb *kiocb, bool wait)
+{
+ struct block_device *bdev = I_BDEV(kiocb->ki_filp->f_mapping->host);
+ struct request_queue *q = bdev_get_queue(bdev);
+
+ return blk_poll(q, READ_ONCE(kiocb->ki_cookie), wait);
+}
+
+static void blkdev_bio_end_io(struct bio *bio)
+{
+ struct blkdev_dio *dio = bio->bi_private;
+ bool should_dirty = dio->should_dirty;
+
+ if (bio->bi_status && !dio->bio.bi_status)
+ dio->bio.bi_status = bio->bi_status;
+
+ if (!dio->multi_bio || atomic_dec_and_test(&dio->ref)) {
+ if (!dio->is_sync) {
+ struct kiocb *iocb = dio->iocb;
+ ssize_t ret;
+
+ if (likely(!dio->bio.bi_status)) {
+ ret = dio->size;
+ iocb->ki_pos += ret;
+ } else {
+ ret = blk_status_to_errno(dio->bio.bi_status);
+ }
+
+ dio->iocb->ki_complete(iocb, ret, 0);
+ if (dio->multi_bio)
+ bio_put(&dio->bio);
+ } else {
+ struct task_struct *waiter = dio->waiter;
+
+ WRITE_ONCE(dio->waiter, NULL);
+ blk_wake_io_task(waiter);
+ }
+ }
+
+ if (should_dirty) {
+ bio_check_pages_dirty(bio);
+ } else {
+ bio_release_pages(bio, false);
+ bio_put(bio);
+ }
+}
+
+static ssize_t __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
+ unsigned int nr_pages)
+{
+ struct file *file = iocb->ki_filp;
+ struct inode *inode = bdev_file_inode(file);
+ struct block_device *bdev = I_BDEV(inode);
+ struct blk_plug plug;
+ struct blkdev_dio *dio;
+ struct bio *bio;
+ bool is_poll = (iocb->ki_flags & IOCB_HIPRI) != 0;
+ bool is_read = (iov_iter_rw(iter) == READ), is_sync;
+ loff_t pos = iocb->ki_pos;
+ blk_qc_t qc = BLK_QC_T_NONE;
+ int ret = 0;
+
+ if ((pos | iov_iter_alignment(iter)) &
+ (bdev_logical_block_size(bdev) - 1))
+ return -EINVAL;
+
+ bio = bio_alloc_kiocb(iocb, nr_pages, &blkdev_dio_pool);
+
+ dio = container_of(bio, struct blkdev_dio, bio);
+ dio->is_sync = is_sync = is_sync_kiocb(iocb);
+ if (dio->is_sync) {
+ dio->waiter = current;
+ bio_get(bio);
+ } else {
+ dio->iocb = iocb;
+ }
+
+ dio->size = 0;
+ dio->multi_bio = false;
+ dio->should_dirty = is_read && iter_is_iovec(iter);
+
+ /*
+ * Don't plug for HIPRI/polled IO, as those should go straight
+ * to issue
+ */
+ if (!is_poll)
+ blk_start_plug(&plug);
+
+ for (;;) {
+ bio_set_dev(bio, bdev);
+ bio->bi_iter.bi_sector = pos >> 9;
+ bio->bi_write_hint = iocb->ki_hint;
+ bio->bi_private = dio;
+ bio->bi_end_io = blkdev_bio_end_io;
+ bio->bi_ioprio = iocb->ki_ioprio;
+
+ ret = bio_iov_iter_get_pages(bio, iter);
+ if (unlikely(ret)) {
+ bio->bi_status = BLK_STS_IOERR;
+ bio_endio(bio);
+ break;
+ }
+
+ if (is_read) {
+ bio->bi_opf = REQ_OP_READ;
+ if (dio->should_dirty)
+ bio_set_pages_dirty(bio);
+ } else {
+ bio->bi_opf = dio_bio_write_op(iocb);
+ task_io_account_write(bio->bi_iter.bi_size);
+ }
+ if (iocb->ki_flags & IOCB_NOWAIT)
+ bio->bi_opf |= REQ_NOWAIT;
+
+ dio->size += bio->bi_iter.bi_size;
+ pos += bio->bi_iter.bi_size;
+
+ nr_pages = bio_iov_vecs_to_alloc(iter, BIO_MAX_VECS);
+ if (!nr_pages) {
+ bool polled = false;
+
+ if (iocb->ki_flags & IOCB_HIPRI) {
+ bio_set_polled(bio, iocb);
+ polled = true;
+ }
+
+ qc = submit_bio(bio);
+
+ if (polled)
+ WRITE_ONCE(iocb->ki_cookie, qc);
+ break;
+ }
+
+ if (!dio->multi_bio) {
+ /*
+ * AIO needs an extra reference to ensure the dio
+ * structure which is embedded into the first bio
+ * stays around.
+ */
+ if (!is_sync)
+ bio_get(bio);
+ dio->multi_bio = true;
+ atomic_set(&dio->ref, 2);
+ } else {
+ atomic_inc(&dio->ref);
+ }
+
+ submit_bio(bio);
+ bio = bio_alloc(GFP_KERNEL, nr_pages);
+ }
+
+ if (!is_poll)
+ blk_finish_plug(&plug);
+
+ if (!is_sync)
+ return -EIOCBQUEUED;
+
+ for (;;) {
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ if (!READ_ONCE(dio->waiter))
+ break;
+
+ if (!(iocb->ki_flags & IOCB_HIPRI) ||
+ !blk_poll(bdev_get_queue(bdev), qc, true))
+ blk_io_schedule();
+ }
+ __set_current_state(TASK_RUNNING);
+
+ if (!ret)
+ ret = blk_status_to_errno(dio->bio.bi_status);
+ if (likely(!ret))
+ ret = dio->size;
+
+ bio_put(&dio->bio);
+ return ret;
+}
+
+static ssize_t blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
+{
+ unsigned int nr_pages;
+
+ if (!iov_iter_count(iter))
+ return 0;
+
+ nr_pages = bio_iov_vecs_to_alloc(iter, BIO_MAX_VECS + 1);
+ if (is_sync_kiocb(iocb) && nr_pages <= BIO_MAX_VECS)
+ return __blkdev_direct_IO_simple(iocb, iter, nr_pages);
+
+ return __blkdev_direct_IO(iocb, iter, bio_max_segs(nr_pages));
+}
+
+static int blkdev_writepage(struct page *page, struct writeback_control *wbc)
+{
+ return block_write_full_page(page, blkdev_get_block, wbc);
+}
+
+static int blkdev_readpage(struct file * file, struct page * page)
+{
+ return block_read_full_page(page, blkdev_get_block);
+}
+
+static void blkdev_readahead(struct readahead_control *rac)
+{
+ mpage_readahead(rac, blkdev_get_block);
+}
+
+static int blkdev_write_begin(struct file *file, struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned flags, struct page **pagep,
+ void **fsdata)
+{
+ return block_write_begin(mapping, pos, len, flags, pagep,
+ blkdev_get_block);
+}
+
+static int blkdev_write_end(struct file *file, struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned copied, struct page *page,
+ void *fsdata)
+{
+ int ret;
+ ret = block_write_end(file, mapping, pos, len, copied, page, fsdata);
+
+ unlock_page(page);
+ put_page(page);
+
+ return ret;
+}
+
+static int blkdev_writepages(struct address_space *mapping,
+ struct writeback_control *wbc)
+{
+ return generic_writepages(mapping, wbc);
+}
+
+const struct address_space_operations def_blk_aops = {
+ .set_page_dirty = __set_page_dirty_buffers,
+ .readpage = blkdev_readpage,
+ .readahead = blkdev_readahead,
+ .writepage = blkdev_writepage,
+ .write_begin = blkdev_write_begin,
+ .write_end = blkdev_write_end,
+ .writepages = blkdev_writepages,
+ .direct_IO = blkdev_direct_IO,
+ .migratepage = buffer_migrate_page_norefs,
+ .is_dirty_writeback = buffer_check_dirty_writeback,
+};
+
+/*
+ * for a block special file file_inode(file)->i_size is zero
+ * so we compute the size by hand (just as in block_read/write above)
+ */
+static loff_t blkdev_llseek(struct file *file, loff_t offset, int whence)
+{
+ struct inode *bd_inode = bdev_file_inode(file);
+ loff_t retval;
+
+ inode_lock(bd_inode);
+ retval = fixed_size_llseek(file, offset, whence, i_size_read(bd_inode));
+ inode_unlock(bd_inode);
+ return retval;
+}
+
+static int blkdev_fsync(struct file *filp, loff_t start, loff_t end,
+ int datasync)
+{
+ struct inode *bd_inode = bdev_file_inode(filp);
+ struct block_device *bdev = I_BDEV(bd_inode);
+ int error;
+
+ error = file_write_and_wait_range(filp, start, end);
+ if (error)
+ return error;
+
+ /*
+ * There is no need to serialise calls to blkdev_issue_flush with
+ * i_mutex and doing so causes performance issues with concurrent
+ * O_SYNC writers to a block device.
+ */
+ error = blkdev_issue_flush(bdev);
+ if (error == -EOPNOTSUPP)
+ error = 0;
+
+ return error;
+}
+
+static int blkdev_open(struct inode *inode, struct file *filp)
+{
+ struct block_device *bdev;
+
+ /*
+ * Preserve backwards compatibility and allow large file access
+ * even if userspace doesn't ask for it explicitly. Some mkfs
+ * binary needs it. We might want to drop this workaround
+ * during an unstable branch.
+ */
+ filp->f_flags |= O_LARGEFILE;
+ filp->f_mode |= FMODE_NOWAIT | FMODE_BUF_RASYNC;
+
+ if (filp->f_flags & O_NDELAY)
+ filp->f_mode |= FMODE_NDELAY;
+ if (filp->f_flags & O_EXCL)
+ filp->f_mode |= FMODE_EXCL;
+ if ((filp->f_flags & O_ACCMODE) == 3)
+ filp->f_mode |= FMODE_WRITE_IOCTL;
+
+ bdev = blkdev_get_by_dev(inode->i_rdev, filp->f_mode, filp);
+ if (IS_ERR(bdev))
+ return PTR_ERR(bdev);
+ filp->f_mapping = bdev->bd_inode->i_mapping;
+ filp->f_wb_err = filemap_sample_wb_err(filp->f_mapping);
+ return 0;
+}
+
+static int blkdev_close(struct inode *inode, struct file *filp)
+{
+ struct block_device *bdev = I_BDEV(bdev_file_inode(filp));
+
+ blkdev_put(bdev, filp->f_mode);
+ return 0;
+}
+
+static long block_ioctl(struct file *file, unsigned cmd, unsigned long arg)
+{
+ struct block_device *bdev = I_BDEV(bdev_file_inode(file));
+ fmode_t mode = file->f_mode;
+
+ /*
+ * O_NDELAY can be altered using fcntl(.., F_SETFL, ..), so we have
+ * to updated it before every ioctl.
+ */
+ if (file->f_flags & O_NDELAY)
+ mode |= FMODE_NDELAY;
+ else
+ mode &= ~FMODE_NDELAY;
+
+ return blkdev_ioctl(bdev, mode, cmd, arg);
+}
+
+/*
+ * Write data to the block device. Only intended for the block device itself
+ * and the raw driver which basically is a fake block device.
+ *
+ * Does not take i_mutex for the write and thus is not for general purpose
+ * use.
+ */
+static ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from)
+{
+ struct file *file = iocb->ki_filp;
+ struct inode *bd_inode = bdev_file_inode(file);
+ loff_t size = i_size_read(bd_inode);
+ struct blk_plug plug;
+ size_t shorted = 0;
+ ssize_t ret;
+
+ if (bdev_read_only(I_BDEV(bd_inode)))
+ return -EPERM;
+
+ if (IS_SWAPFILE(bd_inode) && !is_hibernate_resume_dev(bd_inode->i_rdev))
+ return -ETXTBSY;
+
+ if (!iov_iter_count(from))
+ return 0;
+
+ if (iocb->ki_pos >= size)
+ return -ENOSPC;
+
+ if ((iocb->ki_flags & (IOCB_NOWAIT | IOCB_DIRECT)) == IOCB_NOWAIT)
+ return -EOPNOTSUPP;
+
+ size -= iocb->ki_pos;
+ if (iov_iter_count(from) > size) {
+ shorted = iov_iter_count(from) - size;
+ iov_iter_truncate(from, size);
+ }
+
+ blk_start_plug(&plug);
+ ret = __generic_file_write_iter(iocb, from);
+ if (ret > 0)
+ ret = generic_write_sync(iocb, ret);
+ iov_iter_reexpand(from, iov_iter_count(from) + shorted);
+ blk_finish_plug(&plug);
+ return ret;
+}
+
+static ssize_t blkdev_read_iter(struct kiocb *iocb, struct iov_iter *to)
+{
+ struct file *file = iocb->ki_filp;
+ struct inode *bd_inode = bdev_file_inode(file);
+ loff_t size = i_size_read(bd_inode);
+ loff_t pos = iocb->ki_pos;
+ size_t shorted = 0;
+ ssize_t ret;
+
+ if (pos >= size)
+ return 0;
+
+ size -= pos;
+ if (iov_iter_count(to) > size) {
+ shorted = iov_iter_count(to) - size;
+ iov_iter_truncate(to, size);
+ }
+
+ ret = generic_file_read_iter(iocb, to);
+ iov_iter_reexpand(to, iov_iter_count(to) + shorted);
+ return ret;
+}
+
+#define BLKDEV_FALLOC_FL_SUPPORTED \
+ (FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE | \
+ FALLOC_FL_ZERO_RANGE | FALLOC_FL_NO_HIDE_STALE)
+
+static long blkdev_fallocate(struct file *file, int mode, loff_t start,
+ loff_t len)
+{
+ struct block_device *bdev = I_BDEV(bdev_file_inode(file));
+ loff_t end = start + len - 1;
+ loff_t isize;
+ int error;
+
+ /* Fail if we don't recognize the flags. */
+ if (mode & ~BLKDEV_FALLOC_FL_SUPPORTED)
+ return -EOPNOTSUPP;
+
+ /* Don't go off the end of the device. */
+ isize = i_size_read(bdev->bd_inode);
+ if (start >= isize)
+ return -EINVAL;
+ if (end >= isize) {
+ if (mode & FALLOC_FL_KEEP_SIZE) {
+ len = isize - start;
+ end = start + len - 1;
+ } else
+ return -EINVAL;
+ }
+
+ /*
+ * Don't allow IO that isn't aligned to logical block size.
+ */
+ if ((start | len) & (bdev_logical_block_size(bdev) - 1))
+ return -EINVAL;
+
+ /* Invalidate the page cache, including dirty pages. */
+ error = truncate_bdev_range(bdev, file->f_mode, start, end);
+ if (error)
+ return error;
+
+ switch (mode) {
+ case FALLOC_FL_ZERO_RANGE:
+ case FALLOC_FL_ZERO_RANGE | FALLOC_FL_KEEP_SIZE:
+ error = blkdev_issue_zeroout(bdev, start >> 9, len >> 9,
+ GFP_KERNEL, BLKDEV_ZERO_NOUNMAP);
+ break;
+ case FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE:
+ error = blkdev_issue_zeroout(bdev, start >> 9, len >> 9,
+ GFP_KERNEL, BLKDEV_ZERO_NOFALLBACK);
+ break;
+ case FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE | FALLOC_FL_NO_HIDE_STALE:
+ error = blkdev_issue_discard(bdev, start >> 9, len >> 9,
+ GFP_KERNEL, 0);
+ break;
+ default:
+ return -EOPNOTSUPP;
+ }
+ if (error)
+ return error;
+
+ /*
+ * Invalidate the page cache again; if someone wandered in and dirtied
+ * a page, we just discard it - userspace has no way of knowing whether
+ * the write happened before or after discard completing...
+ */
+ return truncate_bdev_range(bdev, file->f_mode, start, end);
+}
+
+const struct file_operations def_blk_fops = {
+ .open = blkdev_open,
+ .release = blkdev_close,
+ .llseek = blkdev_llseek,
+ .read_iter = blkdev_read_iter,
+ .write_iter = blkdev_write_iter,
+ .iopoll = blkdev_iopoll,
+ .mmap = generic_file_mmap,
+ .fsync = blkdev_fsync,
+ .unlocked_ioctl = block_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = compat_blkdev_ioctl,
+#endif
+ .splice_read = generic_file_splice_read,
+ .splice_write = iter_file_splice_write,
+ .fallocate = blkdev_fallocate,
+};
+
+static __init int blkdev_init(void)
+{
+ return bioset_init(&blkdev_dio_pool, 4,
+ offsetof(struct blkdev_dio, bio),
+ BIOSET_NEED_BVECS|BIOSET_PERCPU_CACHE);
+}
+module_init(blkdev_init);
void (*probe)(dev_t devt);
} *major_names[BLKDEV_MAJOR_HASH_SIZE];
static DEFINE_MUTEX(major_names_lock);
+static DEFINE_SPINLOCK(major_names_spinlock);
/* index in the above - for now: assume no multimajor ranges */
static inline int major_to_index(unsigned major)
{
struct blk_major_name *dp;
- mutex_lock(&major_names_lock);
+ spin_lock(&major_names_spinlock);
for (dp = major_names[major_to_index(offset)]; dp; dp = dp->next)
if (dp->major == offset)
seq_printf(seqf, "%3d %s\n", dp->major, dp->name);
- mutex_unlock(&major_names_lock);
+ spin_unlock(&major_names_spinlock);
}
#endif /* CONFIG_PROC_FS */
p->next = NULL;
index = major_to_index(major);
+ spin_lock(&major_names_spinlock);
for (n = &major_names[index]; *n; n = &(*n)->next) {
if ((*n)->major == major)
break;
*n = p;
else
ret = -EBUSY;
+ spin_unlock(&major_names_spinlock);
if (ret < 0) {
printk("register_blkdev: cannot get major %u for %s\n",
int index = major_to_index(major);
mutex_lock(&major_names_lock);
+ spin_lock(&major_names_spinlock);
for (n = &major_names[index]; *n; n = &(*n)->next)
if ((*n)->major == major)
break;
p = *n;
*n = p->next;
}
+ spin_unlock(&major_names_spinlock);
mutex_unlock(&major_names_lock);
kfree(p);
}
}
reg_base = devm_platform_ioremap_resource(pdev, 0);
- if (!reg_base)
- return -EINVAL;
+ if (IS_ERR(reg_base))
+ return PTR_ERR(reg_base);
disk = blk_alloc_disk(NUMA_NO_NODE);
if (!disk)
static void nvme_put_subsystem(struct nvme_subsystem *subsys);
static void nvme_remove_invalid_namespaces(struct nvme_ctrl *ctrl,
unsigned nsid);
+static void nvme_update_keep_alive(struct nvme_ctrl *ctrl,
+ struct nvme_command *cmd);
/*
* Prepare a queue for teardown.
return effects;
}
-static void nvme_passthru_end(struct nvme_ctrl *ctrl, u32 effects)
+static void nvme_passthru_end(struct nvme_ctrl *ctrl, u32 effects,
+ struct nvme_command *cmd, int status)
{
if (effects & NVME_CMD_EFFECTS_CSE_MASK) {
nvme_unfreeze(ctrl);
nvme_queue_scan(ctrl);
flush_work(&ctrl->scan_work);
}
+
+ switch (cmd->common.opcode) {
+ case nvme_admin_set_features:
+ switch (le32_to_cpu(cmd->common.cdw10) & 0xFF) {
+ case NVME_FEAT_KATO:
+ /*
+ * Keep alive commands interval on the host should be
+ * updated when KATO is modified by Set Features
+ * commands.
+ */
+ if (!status)
+ nvme_update_keep_alive(ctrl, cmd);
+ break;
+ default:
+ break;
+ }
+ break;
+ default:
+ break;
+ }
}
int nvme_execute_passthru_rq(struct request *rq)
effects = nvme_passthru_start(ctrl, ns, cmd->common.opcode);
ret = nvme_execute_rq(disk, rq, false);
if (effects) /* nothing to be done for zero cmd effects */
- nvme_passthru_end(ctrl, effects);
+ nvme_passthru_end(ctrl, effects, cmd, ret);
return ret;
}
}
EXPORT_SYMBOL_GPL(nvme_stop_keep_alive);
+static void nvme_update_keep_alive(struct nvme_ctrl *ctrl,
+ struct nvme_command *cmd)
+{
+ unsigned int new_kato =
+ DIV_ROUND_UP(le32_to_cpu(cmd->common.cdw11), 1000);
+
+ dev_info(ctrl->device,
+ "keep alive interval updated from %u ms to %u ms\n",
+ ctrl->kato * 1000 / 2, new_kato * 1000 / 2);
+
+ nvme_stop_keep_alive(ctrl);
+ ctrl->kato = new_kato;
+ nvme_start_keep_alive(ctrl);
+}
+
/*
* In NVMe 1.0 the CNS field was just a binary controller or namespace
* flag, thus sending any new CNS opcodes has a big chance of not working.
return error;
}
-static bool nvme_multi_css(struct nvme_ctrl *ctrl)
-{
- return (ctrl->ctrl_config & NVME_CC_CSS_MASK) == NVME_CC_CSS_CSI;
-}
-
static int nvme_process_ns_desc(struct nvme_ctrl *ctrl, struct nvme_ns_ids *ids,
struct nvme_ns_id_desc *cur, bool *csi_seen)
{
goto out_unfreeze;
}
+ set_bit(NVME_NS_READY, &ns->flags);
blk_mq_unfreeze_queue(ns->disk->queue);
if (blk_queue_is_zoned(ns->queue)) {
if (nvme_ns_head_multipath(ns->head)) {
blk_mq_freeze_queue(ns->head->disk->queue);
nvme_update_disk_info(ns->head->disk, ns, id);
+ nvme_mpath_revalidate_paths(ns);
blk_stack_limits(&ns->head->disk->queue->limits,
&ns->queue->limits, 0);
disk_update_readahead(ns->head->disk);
nvme_get_ctrl(ctrl);
- device_add_disk(ctrl->device, ns->disk, nvme_ns_id_attr_groups);
+ if (device_add_disk(ctrl->device, ns->disk, nvme_ns_id_attr_groups))
+ goto out_cleanup_ns_from_list;
+
if (!nvme_ns_head_multipath(ns->head))
nvme_add_ns_cdev(ns);
return;
+ out_cleanup_ns_from_list:
+ nvme_put_ctrl(ctrl);
+ down_write(&ctrl->namespaces_rwsem);
+ list_del_init(&ns->list);
+ up_write(&ctrl->namespaces_rwsem);
out_unlink_ns:
mutex_lock(&ctrl->subsys->lock);
list_del_rcu(&ns->siblings);
if (test_and_set_bit(NVME_NS_REMOVING, &ns->flags))
return;
+ clear_bit(NVME_NS_READY, &ns->flags);
set_capacity(ns->disk, 0);
nvme_fault_inject_fini(&ns->fault_inject);
list_del_rcu(&ns->siblings);
mutex_unlock(&ns->ctrl->subsys->lock);
- synchronize_rcu(); /* guarantee not available in head->list */
- nvme_mpath_clear_current_path(ns);
- synchronize_srcu(&ns->head->srcu); /* wait for concurrent submissions */
+ /* guarantee not available in head->list */
+ synchronize_rcu();
+
+ /* wait for concurrent submissions */
+ if (nvme_mpath_clear_current_path(ns))
+ synchronize_srcu(&ns->head->srcu);
if (!nvme_ns_head_multipath(ns->head))
nvme_cdev_del(&ns->cdev, &ns->cdev_device);
mutex_unlock(&ctrl->scan_lock);
}
+void nvme_mpath_revalidate_paths(struct nvme_ns *ns)
+{
+ struct nvme_ns_head *head = ns->head;
+ sector_t capacity = get_capacity(head->disk);
+ int node;
+
+ list_for_each_entry_rcu(ns, &head->list, siblings) {
+ if (capacity != get_capacity(ns->disk))
+ clear_bit(NVME_NS_READY, &ns->flags);
+ }
+
+ for_each_node(node)
+ rcu_assign_pointer(head->current_path[node], NULL);
+}
+
static bool nvme_path_is_disabled(struct nvme_ns *ns)
{
/*
ns->ctrl->state != NVME_CTRL_DELETING)
return true;
if (test_bit(NVME_NS_ANA_PENDING, &ns->flags) ||
- test_bit(NVME_NS_REMOVING, &ns->flags))
+ !test_bit(NVME_NS_READY, &ns->flags))
return true;
return false;
}
ctrl->subsys->instance, head->instance);
blk_queue_flag_set(QUEUE_FLAG_NONROT, head->disk->queue);
+ blk_queue_flag_set(QUEUE_FLAG_NOWAIT, head->disk->queue);
+
/* set to a default value of 512 until the disk is validated */
blk_queue_logical_block_size(head->disk->queue, 512);
blk_set_stacking_limits(&head->disk->queue->limits);
#define NVME_NS_DEAD 1
#define NVME_NS_ANA_PENDING 2
#define NVME_NS_FORCE_RO 3
+#define NVME_NS_READY 4
struct cdev cdev;
struct device cdev_device;
void nvme_mpath_uninit(struct nvme_ctrl *ctrl);
void nvme_mpath_stop(struct nvme_ctrl *ctrl);
bool nvme_mpath_clear_current_path(struct nvme_ns *ns);
+void nvme_mpath_revalidate_paths(struct nvme_ns *ns);
void nvme_mpath_clear_ctrl_paths(struct nvme_ctrl *ctrl);
void nvme_mpath_shutdown_disk(struct nvme_ns_head *head);
{
return false;
}
+static inline void nvme_mpath_revalidate_paths(struct nvme_ns *ns)
+{
+}
static inline void nvme_mpath_clear_ctrl_paths(struct nvme_ctrl *ctrl)
{
}
struct nvme_ns *nvme_find_get_ns(struct nvme_ctrl *ctrl, unsigned nsid);
void nvme_put_ns(struct nvme_ns *ns);
+static inline bool nvme_multi_css(struct nvme_ctrl *ctrl)
+{
+ return (ctrl->ctrl_config & NVME_CC_CSS_MASK) == NVME_CC_CSS_CSI;
+}
+
#endif /* _NVME_H */
u32 pdu_len;
u32 pdu_sent;
u16 ttag;
+ __le16 status;
struct list_head entry;
struct llist_node lentry;
__le32 ddgst;
static int nvme_tcp_process_nvme_cqe(struct nvme_tcp_queue *queue,
struct nvme_completion *cqe)
{
+ struct nvme_tcp_request *req;
struct request *rq;
rq = nvme_find_rq(nvme_tcp_tagset(queue), cqe->command_id);
return -EINVAL;
}
- if (!nvme_try_complete_req(rq, cqe->status, cqe->result))
+ req = blk_mq_rq_to_pdu(rq);
+ if (req->status == cpu_to_le16(NVME_SC_SUCCESS))
+ req->status = cqe->status;
+
+ if (!nvme_try_complete_req(rq, req->status, cqe->result))
nvme_complete_rq(rq);
queue->nr_cqe++;
queue->ddgst_remaining = NVME_TCP_DIGEST_LENGTH;
} else {
if (pdu->hdr.flags & NVME_TCP_F_DATA_SUCCESS) {
- nvme_tcp_end_request(rq, NVME_SC_SUCCESS);
+ nvme_tcp_end_request(rq,
+ le16_to_cpu(req->status));
queue->nr_cqe++;
}
nvme_tcp_init_recv_ctx(queue);
return 0;
if (queue->recv_ddgst != queue->exp_ddgst) {
+ struct request *rq = nvme_cid_to_rq(nvme_tcp_tagset(queue),
+ pdu->command_id);
+ struct nvme_tcp_request *req = blk_mq_rq_to_pdu(rq);
+
+ req->status = cpu_to_le16(NVME_SC_DATA_XFER_ERROR);
+
dev_err(queue->ctrl->ctrl.device,
"data digest error: recv %#x expected %#x\n",
le32_to_cpu(queue->recv_ddgst),
le32_to_cpu(queue->exp_ddgst));
- return -EIO;
}
if (pdu->hdr.flags & NVME_TCP_F_DATA_SUCCESS) {
struct request *rq = nvme_cid_to_rq(nvme_tcp_tagset(queue),
pdu->command_id);
+ struct nvme_tcp_request *req = blk_mq_rq_to_pdu(rq);
- nvme_tcp_end_request(rq, NVME_SC_SUCCESS);
+ nvme_tcp_end_request(rq, le16_to_cpu(req->status));
queue->nr_cqe++;
}
return ret;
req->state = NVME_TCP_SEND_CMD_PDU;
+ req->status = cpu_to_le16(NVME_SC_SUCCESS);
req->offset = 0;
req->data_sent = 0;
req->pdu_len = 0;
if (unlikely(ret))
return ret;
- if (nvmet_req_passthru_ctrl(req))
+ if (nvmet_is_passthru_req(req))
return nvmet_parse_passthru_admin_cmd(req);
switch (cmd->common.opcode) {
}
/* passthru subsystems use the underlying controller's version */
- if (nvmet_passthru_ctrl(subsys))
+ if (nvmet_is_passthru_subsys(subsys))
return -EINVAL;
ret = sscanf(page, "%d.%d.%d\n", &major, &minor, &tertiary);
{
struct nvmet_subsys *subsys = to_subsys(item);
- return snprintf(page, PAGE_SIZE, "%s\n", subsys->serial);
+ return snprintf(page, PAGE_SIZE, "%*s\n",
+ NVMET_SN_MAX_SIZE, subsys->serial);
}
static ssize_t
mutex_lock(&subsys->lock);
ret = 0;
- if (nvmet_passthru_ctrl(subsys)) {
+ if (nvmet_is_passthru_subsys(subsys)) {
pr_info("cannot enable both passthru and regular namespaces for a single subsystem");
goto out_unlock;
}
if (unlikely(ret))
return ret;
- if (nvmet_req_passthru_ctrl(req))
+ if (nvmet_is_passthru_req(req))
return nvmet_parse_passthru_io_cmd(req);
ret = nvmet_req_find_ns(req);
ctrl->cap |= (15ULL << 24);
/* maximum queue entries supported: */
ctrl->cap |= NVMET_QUEUE_SIZE - 1;
+
+ if (nvmet_is_passthru_subsys(ctrl->subsys))
+ nvmet_passthrough_override_cap(ctrl);
}
struct nvmet_ctrl *nvmet_ctrl_find_get(const char *subsysnqn,
goto out_put_subsystem;
mutex_init(&ctrl->lock);
- nvmet_init_cap(ctrl);
-
ctrl->port = req->port;
INIT_WORK(&ctrl->async_event_work, nvmet_async_event_work);
kref_init(&ctrl->ref);
ctrl->subsys = subsys;
+ nvmet_init_cap(ctrl);
WRITE_ONCE(ctrl->aen_enabled, NVMET_AEN_CFG_OPTIONAL);
ctrl->changed_ns_list = kmalloc_array(NVME_MAX_CHANGED_NAMESPACES,
void nvmet_passthru_ctrl_disable(struct nvmet_subsys *subsys);
u16 nvmet_parse_passthru_admin_cmd(struct nvmet_req *req);
u16 nvmet_parse_passthru_io_cmd(struct nvmet_req *req);
-static inline struct nvme_ctrl *nvmet_passthru_ctrl(struct nvmet_subsys *subsys)
+static inline bool nvmet_is_passthru_subsys(struct nvmet_subsys *subsys)
{
return subsys->passthru_ctrl;
}
{
return 0;
}
-static inline struct nvme_ctrl *nvmet_passthru_ctrl(struct nvmet_subsys *subsys)
+static inline bool nvmet_is_passthru_subsys(struct nvmet_subsys *subsys)
{
return NULL;
}
#endif /* CONFIG_NVME_TARGET_PASSTHRU */
-static inline struct nvme_ctrl *
-nvmet_req_passthru_ctrl(struct nvmet_req *req)
+static inline bool nvmet_is_passthru_req(struct nvmet_req *req)
{
- return nvmet_passthru_ctrl(nvmet_req_subsys(req));
+ return nvmet_is_passthru_subsys(nvmet_req_subsys(req));
}
+void nvmet_passthrough_override_cap(struct nvmet_ctrl *ctrl);
+
u16 errno_to_nvme_status(struct nvmet_req *req, int errno);
u16 nvmet_report_invalid_opcode(struct nvmet_req *req);
*/
static DEFINE_XARRAY(passthru_subsystems);
+void nvmet_passthrough_override_cap(struct nvmet_ctrl *ctrl)
+{
+ /*
+ * Multiple command set support can only be declared if the underlying
+ * controller actually supports it.
+ */
+ if (!nvme_multi_css(ctrl->subsys->passthru_ctrl))
+ ctrl->cap &= ~(1ULL << 43);
+}
+
static u16 nvmet_passthru_override_id_ctrl(struct nvmet_req *req)
{
struct nvmet_ctrl *ctrl = req->sq->ctrl;
static void nvmet_passthru_execute_cmd(struct nvmet_req *req)
{
- struct nvme_ctrl *ctrl = nvmet_req_passthru_ctrl(req);
+ struct nvme_ctrl *ctrl = nvmet_req_subsys(req)->passthru_ctrl;
struct request_queue *q = ctrl->admin_q;
struct nvme_ns *ns = NULL;
struct request *rq = NULL;
*/
static void nvmet_passthru_set_host_behaviour(struct nvmet_req *req)
{
- struct nvme_ctrl *ctrl = nvmet_req_passthru_ctrl(req);
+ struct nvme_ctrl *ctrl = nvmet_req_subsys(req)->passthru_ctrl;
struct nvme_feat_host_behavior *host;
u16 status = NVME_SC_INTERNAL;
int ret;
kernel_read_file.o remap_range.o
ifeq ($(CONFIG_BLOCK),y)
-obj-y += buffer.o block_dev.o direct-io.o mpage.o
+obj-y += buffer.o direct-io.o mpage.o
else
obj-y += no-block.o
endif
+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * Copyright (C) 1991, 1992 Linus Torvalds
- * Copyright (C) 2001 Andrea Arcangeli <andrea@suse.de> SuSE
- * Copyright (C) 2016 - 2020 Christoph Hellwig
- */
-
-#include <linux/init.h>
-#include <linux/mm.h>
-#include <linux/fcntl.h>
-#include <linux/slab.h>
-#include <linux/kmod.h>
-#include <linux/major.h>
-#include <linux/device_cgroup.h>
-#include <linux/highmem.h>
-#include <linux/blkdev.h>
-#include <linux/backing-dev.h>
-#include <linux/module.h>
-#include <linux/blkpg.h>
-#include <linux/magic.h>
-#include <linux/buffer_head.h>
-#include <linux/swap.h>
-#include <linux/pagevec.h>
-#include <linux/writeback.h>
-#include <linux/mpage.h>
-#include <linux/mount.h>
-#include <linux/pseudo_fs.h>
-#include <linux/uio.h>
-#include <linux/namei.h>
-#include <linux/log2.h>
-#include <linux/cleancache.h>
-#include <linux/task_io_accounting_ops.h>
-#include <linux/falloc.h>
-#include <linux/part_stat.h>
-#include <linux/uaccess.h>
-#include <linux/suspend.h>
-#include "internal.h"
-#include "../block/blk.h"
-
-struct bdev_inode {
- struct block_device bdev;
- struct inode vfs_inode;
-};
-
-static const struct address_space_operations def_blk_aops;
-
-static inline struct bdev_inode *BDEV_I(struct inode *inode)
-{
- return container_of(inode, struct bdev_inode, vfs_inode);
-}
-
-struct block_device *I_BDEV(struct inode *inode)
-{
- return &BDEV_I(inode)->bdev;
-}
-EXPORT_SYMBOL(I_BDEV);
-
-static void bdev_write_inode(struct block_device *bdev)
-{
- struct inode *inode = bdev->bd_inode;
- int ret;
-
- spin_lock(&inode->i_lock);
- while (inode->i_state & I_DIRTY) {
- spin_unlock(&inode->i_lock);
- ret = write_inode_now(inode, true);
- if (ret) {
- char name[BDEVNAME_SIZE];
- pr_warn_ratelimited("VFS: Dirty inode writeback failed "
- "for block device %s (err=%d).\n",
- bdevname(bdev, name), ret);
- }
- spin_lock(&inode->i_lock);
- }
- spin_unlock(&inode->i_lock);
-}
-
-/* Kill _all_ buffers and pagecache , dirty or not.. */
-static void kill_bdev(struct block_device *bdev)
-{
- struct address_space *mapping = bdev->bd_inode->i_mapping;
-
- if (mapping_empty(mapping))
- return;
-
- invalidate_bh_lrus();
- truncate_inode_pages(mapping, 0);
-}
-
-/* Invalidate clean unused buffers and pagecache. */
-void invalidate_bdev(struct block_device *bdev)
-{
- struct address_space *mapping = bdev->bd_inode->i_mapping;
-
- if (mapping->nrpages) {
- invalidate_bh_lrus();
- lru_add_drain_all(); /* make sure all lru add caches are flushed */
- invalidate_mapping_pages(mapping, 0, -1);
- }
- /* 99% of the time, we don't need to flush the cleancache on the bdev.
- * But, for the strange corners, lets be cautious
- */
- cleancache_invalidate_inode(mapping);
-}
-EXPORT_SYMBOL(invalidate_bdev);
-
-/*
- * Drop all buffers & page cache for given bdev range. This function bails
- * with error if bdev has other exclusive owner (such as filesystem).
- */
-int truncate_bdev_range(struct block_device *bdev, fmode_t mode,
- loff_t lstart, loff_t lend)
-{
- /*
- * If we don't hold exclusive handle for the device, upgrade to it
- * while we discard the buffer cache to avoid discarding buffers
- * under live filesystem.
- */
- if (!(mode & FMODE_EXCL)) {
- int err = bd_prepare_to_claim(bdev, truncate_bdev_range);
- if (err)
- goto invalidate;
- }
-
- truncate_inode_pages_range(bdev->bd_inode->i_mapping, lstart, lend);
- if (!(mode & FMODE_EXCL))
- bd_abort_claiming(bdev, truncate_bdev_range);
- return 0;
-
-invalidate:
- /*
- * Someone else has handle exclusively open. Try invalidating instead.
- * The 'end' argument is inclusive so the rounding is safe.
- */
- return invalidate_inode_pages2_range(bdev->bd_inode->i_mapping,
- lstart >> PAGE_SHIFT,
- lend >> PAGE_SHIFT);
-}
-
-static void set_init_blocksize(struct block_device *bdev)
-{
- unsigned int bsize = bdev_logical_block_size(bdev);
- loff_t size = i_size_read(bdev->bd_inode);
-
- while (bsize < PAGE_SIZE) {
- if (size & bsize)
- break;
- bsize <<= 1;
- }
- bdev->bd_inode->i_blkbits = blksize_bits(bsize);
-}
-
-int set_blocksize(struct block_device *bdev, int size)
-{
- /* Size must be a power of two, and between 512 and PAGE_SIZE */
- if (size > PAGE_SIZE || size < 512 || !is_power_of_2(size))
- return -EINVAL;
-
- /* Size cannot be smaller than the size supported by the device */
- if (size < bdev_logical_block_size(bdev))
- return -EINVAL;
-
- /* Don't change the size if it is same as current */
- if (bdev->bd_inode->i_blkbits != blksize_bits(size)) {
- sync_blockdev(bdev);
- bdev->bd_inode->i_blkbits = blksize_bits(size);
- kill_bdev(bdev);
- }
- return 0;
-}
-
-EXPORT_SYMBOL(set_blocksize);
-
-int sb_set_blocksize(struct super_block *sb, int size)
-{
- if (set_blocksize(sb->s_bdev, size))
- return 0;
- /* If we get here, we know size is power of two
- * and it's value is between 512 and PAGE_SIZE */
- sb->s_blocksize = size;
- sb->s_blocksize_bits = blksize_bits(size);
- return sb->s_blocksize;
-}
-
-EXPORT_SYMBOL(sb_set_blocksize);
-
-int sb_min_blocksize(struct super_block *sb, int size)
-{
- int minsize = bdev_logical_block_size(sb->s_bdev);
- if (size < minsize)
- size = minsize;
- return sb_set_blocksize(sb, size);
-}
-
-EXPORT_SYMBOL(sb_min_blocksize);
-
-static int
-blkdev_get_block(struct inode *inode, sector_t iblock,
- struct buffer_head *bh, int create)
-{
- bh->b_bdev = I_BDEV(inode);
- bh->b_blocknr = iblock;
- set_buffer_mapped(bh);
- return 0;
-}
-
-static struct inode *bdev_file_inode(struct file *file)
-{
- return file->f_mapping->host;
-}
-
-static unsigned int dio_bio_write_op(struct kiocb *iocb)
-{
- unsigned int op = REQ_OP_WRITE | REQ_SYNC | REQ_IDLE;
-
- /* avoid the need for a I/O completion work item */
- if (iocb->ki_flags & IOCB_DSYNC)
- op |= REQ_FUA;
- return op;
-}
-
-#define DIO_INLINE_BIO_VECS 4
-
-static void blkdev_bio_end_io_simple(struct bio *bio)
-{
- struct task_struct *waiter = bio->bi_private;
-
- WRITE_ONCE(bio->bi_private, NULL);
- blk_wake_io_task(waiter);
-}
-
-static ssize_t
-__blkdev_direct_IO_simple(struct kiocb *iocb, struct iov_iter *iter,
- unsigned int nr_pages)
-{
- struct file *file = iocb->ki_filp;
- struct block_device *bdev = I_BDEV(bdev_file_inode(file));
- struct bio_vec inline_vecs[DIO_INLINE_BIO_VECS], *vecs;
- loff_t pos = iocb->ki_pos;
- bool should_dirty = false;
- struct bio bio;
- ssize_t ret;
- blk_qc_t qc;
-
- if ((pos | iov_iter_alignment(iter)) &
- (bdev_logical_block_size(bdev) - 1))
- return -EINVAL;
-
- if (nr_pages <= DIO_INLINE_BIO_VECS)
- vecs = inline_vecs;
- else {
- vecs = kmalloc_array(nr_pages, sizeof(struct bio_vec),
- GFP_KERNEL);
- if (!vecs)
- return -ENOMEM;
- }
-
- bio_init(&bio, vecs, nr_pages);
- bio_set_dev(&bio, bdev);
- bio.bi_iter.bi_sector = pos >> 9;
- bio.bi_write_hint = iocb->ki_hint;
- bio.bi_private = current;
- bio.bi_end_io = blkdev_bio_end_io_simple;
- bio.bi_ioprio = iocb->ki_ioprio;
-
- ret = bio_iov_iter_get_pages(&bio, iter);
- if (unlikely(ret))
- goto out;
- ret = bio.bi_iter.bi_size;
-
- if (iov_iter_rw(iter) == READ) {
- bio.bi_opf = REQ_OP_READ;
- if (iter_is_iovec(iter))
- should_dirty = true;
- } else {
- bio.bi_opf = dio_bio_write_op(iocb);
- task_io_account_write(ret);
- }
- if (iocb->ki_flags & IOCB_NOWAIT)
- bio.bi_opf |= REQ_NOWAIT;
- if (iocb->ki_flags & IOCB_HIPRI)
- bio_set_polled(&bio, iocb);
-
- qc = submit_bio(&bio);
- for (;;) {
- set_current_state(TASK_UNINTERRUPTIBLE);
- if (!READ_ONCE(bio.bi_private))
- break;
- if (!(iocb->ki_flags & IOCB_HIPRI) ||
- !blk_poll(bdev_get_queue(bdev), qc, true))
- blk_io_schedule();
- }
- __set_current_state(TASK_RUNNING);
-
- bio_release_pages(&bio, should_dirty);
- if (unlikely(bio.bi_status))
- ret = blk_status_to_errno(bio.bi_status);
-
-out:
- if (vecs != inline_vecs)
- kfree(vecs);
-
- bio_uninit(&bio);
-
- return ret;
-}
-
-struct blkdev_dio {
- union {
- struct kiocb *iocb;
- struct task_struct *waiter;
- };
- size_t size;
- atomic_t ref;
- bool multi_bio : 1;
- bool should_dirty : 1;
- bool is_sync : 1;
- struct bio bio;
-};
-
-static struct bio_set blkdev_dio_pool;
-
-static int blkdev_iopoll(struct kiocb *kiocb, bool wait)
-{
- struct block_device *bdev = I_BDEV(kiocb->ki_filp->f_mapping->host);
- struct request_queue *q = bdev_get_queue(bdev);
-
- return blk_poll(q, READ_ONCE(kiocb->ki_cookie), wait);
-}
-
-static void blkdev_bio_end_io(struct bio *bio)
-{
- struct blkdev_dio *dio = bio->bi_private;
- bool should_dirty = dio->should_dirty;
-
- if (bio->bi_status && !dio->bio.bi_status)
- dio->bio.bi_status = bio->bi_status;
-
- if (!dio->multi_bio || atomic_dec_and_test(&dio->ref)) {
- if (!dio->is_sync) {
- struct kiocb *iocb = dio->iocb;
- ssize_t ret;
-
- if (likely(!dio->bio.bi_status)) {
- ret = dio->size;
- iocb->ki_pos += ret;
- } else {
- ret = blk_status_to_errno(dio->bio.bi_status);
- }
-
- dio->iocb->ki_complete(iocb, ret, 0);
- if (dio->multi_bio)
- bio_put(&dio->bio);
- } else {
- struct task_struct *waiter = dio->waiter;
-
- WRITE_ONCE(dio->waiter, NULL);
- blk_wake_io_task(waiter);
- }
- }
-
- if (should_dirty) {
- bio_check_pages_dirty(bio);
- } else {
- bio_release_pages(bio, false);
- bio_put(bio);
- }
-}
-
-static ssize_t __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
- unsigned int nr_pages)
-{
- struct file *file = iocb->ki_filp;
- struct inode *inode = bdev_file_inode(file);
- struct block_device *bdev = I_BDEV(inode);
- struct blk_plug plug;
- struct blkdev_dio *dio;
- struct bio *bio;
- bool is_poll = (iocb->ki_flags & IOCB_HIPRI) != 0;
- bool is_read = (iov_iter_rw(iter) == READ), is_sync;
- loff_t pos = iocb->ki_pos;
- blk_qc_t qc = BLK_QC_T_NONE;
- int ret = 0;
-
- if ((pos | iov_iter_alignment(iter)) &
- (bdev_logical_block_size(bdev) - 1))
- return -EINVAL;
-
- bio = bio_alloc_kiocb(iocb, nr_pages, &blkdev_dio_pool);
-
- dio = container_of(bio, struct blkdev_dio, bio);
- dio->is_sync = is_sync = is_sync_kiocb(iocb);
- if (dio->is_sync) {
- dio->waiter = current;
- bio_get(bio);
- } else {
- dio->iocb = iocb;
- }
-
- dio->size = 0;
- dio->multi_bio = false;
- dio->should_dirty = is_read && iter_is_iovec(iter);
-
- /*
- * Don't plug for HIPRI/polled IO, as those should go straight
- * to issue
- */
- if (!is_poll)
- blk_start_plug(&plug);
-
- for (;;) {
- bio_set_dev(bio, bdev);
- bio->bi_iter.bi_sector = pos >> 9;
- bio->bi_write_hint = iocb->ki_hint;
- bio->bi_private = dio;
- bio->bi_end_io = blkdev_bio_end_io;
- bio->bi_ioprio = iocb->ki_ioprio;
-
- ret = bio_iov_iter_get_pages(bio, iter);
- if (unlikely(ret)) {
- bio->bi_status = BLK_STS_IOERR;
- bio_endio(bio);
- break;
- }
-
- if (is_read) {
- bio->bi_opf = REQ_OP_READ;
- if (dio->should_dirty)
- bio_set_pages_dirty(bio);
- } else {
- bio->bi_opf = dio_bio_write_op(iocb);
- task_io_account_write(bio->bi_iter.bi_size);
- }
- if (iocb->ki_flags & IOCB_NOWAIT)
- bio->bi_opf |= REQ_NOWAIT;
-
- dio->size += bio->bi_iter.bi_size;
- pos += bio->bi_iter.bi_size;
-
- nr_pages = bio_iov_vecs_to_alloc(iter, BIO_MAX_VECS);
- if (!nr_pages) {
- bool polled = false;
-
- if (iocb->ki_flags & IOCB_HIPRI) {
- bio_set_polled(bio, iocb);
- polled = true;
- }
-
- qc = submit_bio(bio);
-
- if (polled)
- WRITE_ONCE(iocb->ki_cookie, qc);
- break;
- }
-
- if (!dio->multi_bio) {
- /*
- * AIO needs an extra reference to ensure the dio
- * structure which is embedded into the first bio
- * stays around.
- */
- if (!is_sync)
- bio_get(bio);
- dio->multi_bio = true;
- atomic_set(&dio->ref, 2);
- } else {
- atomic_inc(&dio->ref);
- }
-
- submit_bio(bio);
- bio = bio_alloc(GFP_KERNEL, nr_pages);
- }
-
- if (!is_poll)
- blk_finish_plug(&plug);
-
- if (!is_sync)
- return -EIOCBQUEUED;
-
- for (;;) {
- set_current_state(TASK_UNINTERRUPTIBLE);
- if (!READ_ONCE(dio->waiter))
- break;
-
- if (!(iocb->ki_flags & IOCB_HIPRI) ||
- !blk_poll(bdev_get_queue(bdev), qc, true))
- blk_io_schedule();
- }
- __set_current_state(TASK_RUNNING);
-
- if (!ret)
- ret = blk_status_to_errno(dio->bio.bi_status);
- if (likely(!ret))
- ret = dio->size;
-
- bio_put(&dio->bio);
- return ret;
-}
-
-static ssize_t
-blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
-{
- unsigned int nr_pages;
-
- if (!iov_iter_count(iter))
- return 0;
-
- nr_pages = bio_iov_vecs_to_alloc(iter, BIO_MAX_VECS + 1);
- if (is_sync_kiocb(iocb) && nr_pages <= BIO_MAX_VECS)
- return __blkdev_direct_IO_simple(iocb, iter, nr_pages);
-
- return __blkdev_direct_IO(iocb, iter, bio_max_segs(nr_pages));
-}
-
-static __init int blkdev_init(void)
-{
- return bioset_init(&blkdev_dio_pool, 4,
- offsetof(struct blkdev_dio, bio),
- BIOSET_NEED_BVECS|BIOSET_PERCPU_CACHE);
-}
-module_init(blkdev_init);
-
-int __sync_blockdev(struct block_device *bdev, int wait)
-{
- if (!bdev)
- return 0;
- if (!wait)
- return filemap_flush(bdev->bd_inode->i_mapping);
- return filemap_write_and_wait(bdev->bd_inode->i_mapping);
-}
-
-/*
- * Write out and wait upon all the dirty data associated with a block
- * device via its mapping. Does not take the superblock lock.
- */
-int sync_blockdev(struct block_device *bdev)
-{
- return __sync_blockdev(bdev, 1);
-}
-EXPORT_SYMBOL(sync_blockdev);
-
-/*
- * Write out and wait upon all dirty data associated with this
- * device. Filesystem data as well as the underlying block
- * device. Takes the superblock lock.
- */
-int fsync_bdev(struct block_device *bdev)
-{
- struct super_block *sb = get_super(bdev);
- if (sb) {
- int res = sync_filesystem(sb);
- drop_super(sb);
- return res;
- }
- return sync_blockdev(bdev);
-}
-EXPORT_SYMBOL(fsync_bdev);
-
-/**
- * freeze_bdev -- lock a filesystem and force it into a consistent state
- * @bdev: blockdevice to lock
- *
- * If a superblock is found on this device, we take the s_umount semaphore
- * on it to make sure nobody unmounts until the snapshot creation is done.
- * The reference counter (bd_fsfreeze_count) guarantees that only the last
- * unfreeze process can unfreeze the frozen filesystem actually when multiple
- * freeze requests arrive simultaneously. It counts up in freeze_bdev() and
- * count down in thaw_bdev(). When it becomes 0, thaw_bdev() will unfreeze
- * actually.
- */
-int freeze_bdev(struct block_device *bdev)
-{
- struct super_block *sb;
- int error = 0;
-
- mutex_lock(&bdev->bd_fsfreeze_mutex);
- if (++bdev->bd_fsfreeze_count > 1)
- goto done;
-
- sb = get_active_super(bdev);
- if (!sb)
- goto sync;
- if (sb->s_op->freeze_super)
- error = sb->s_op->freeze_super(sb);
- else
- error = freeze_super(sb);
- deactivate_super(sb);
-
- if (error) {
- bdev->bd_fsfreeze_count--;
- goto done;
- }
- bdev->bd_fsfreeze_sb = sb;
-
-sync:
- sync_blockdev(bdev);
-done:
- mutex_unlock(&bdev->bd_fsfreeze_mutex);
- return error;
-}
-EXPORT_SYMBOL(freeze_bdev);
-
-/**
- * thaw_bdev -- unlock filesystem
- * @bdev: blockdevice to unlock
- *
- * Unlocks the filesystem and marks it writeable again after freeze_bdev().
- */
-int thaw_bdev(struct block_device *bdev)
-{
- struct super_block *sb;
- int error = -EINVAL;
-
- mutex_lock(&bdev->bd_fsfreeze_mutex);
- if (!bdev->bd_fsfreeze_count)
- goto out;
-
- error = 0;
- if (--bdev->bd_fsfreeze_count > 0)
- goto out;
-
- sb = bdev->bd_fsfreeze_sb;
- if (!sb)
- goto out;
-
- if (sb->s_op->thaw_super)
- error = sb->s_op->thaw_super(sb);
- else
- error = thaw_super(sb);
- if (error)
- bdev->bd_fsfreeze_count++;
- else
- bdev->bd_fsfreeze_sb = NULL;
-out:
- mutex_unlock(&bdev->bd_fsfreeze_mutex);
- return error;
-}
-EXPORT_SYMBOL(thaw_bdev);
-
-static int blkdev_writepage(struct page *page, struct writeback_control *wbc)
-{
- return block_write_full_page(page, blkdev_get_block, wbc);
-}
-
-static int blkdev_readpage(struct file * file, struct page * page)
-{
- return block_read_full_page(page, blkdev_get_block);
-}
-
-static void blkdev_readahead(struct readahead_control *rac)
-{
- mpage_readahead(rac, blkdev_get_block);
-}
-
-static int blkdev_write_begin(struct file *file, struct address_space *mapping,
- loff_t pos, unsigned len, unsigned flags,
- struct page **pagep, void **fsdata)
-{
- return block_write_begin(mapping, pos, len, flags, pagep,
- blkdev_get_block);
-}
-
-static int blkdev_write_end(struct file *file, struct address_space *mapping,
- loff_t pos, unsigned len, unsigned copied,
- struct page *page, void *fsdata)
-{
- int ret;
- ret = block_write_end(file, mapping, pos, len, copied, page, fsdata);
-
- unlock_page(page);
- put_page(page);
-
- return ret;
-}
-
-/*
- * private llseek:
- * for a block special file file_inode(file)->i_size is zero
- * so we compute the size by hand (just as in block_read/write above)
- */
-static loff_t block_llseek(struct file *file, loff_t offset, int whence)
-{
- struct inode *bd_inode = bdev_file_inode(file);
- loff_t retval;
-
- inode_lock(bd_inode);
- retval = fixed_size_llseek(file, offset, whence, i_size_read(bd_inode));
- inode_unlock(bd_inode);
- return retval;
-}
-
-static int blkdev_fsync(struct file *filp, loff_t start, loff_t end,
- int datasync)
-{
- struct inode *bd_inode = bdev_file_inode(filp);
- struct block_device *bdev = I_BDEV(bd_inode);
- int error;
-
- error = file_write_and_wait_range(filp, start, end);
- if (error)
- return error;
-
- /*
- * There is no need to serialise calls to blkdev_issue_flush with
- * i_mutex and doing so causes performance issues with concurrent
- * O_SYNC writers to a block device.
- */
- error = blkdev_issue_flush(bdev);
- if (error == -EOPNOTSUPP)
- error = 0;
-
- return error;
-}
-
-/**
- * bdev_read_page() - Start reading a page from a block device
- * @bdev: The device to read the page from
- * @sector: The offset on the device to read the page to (need not be aligned)
- * @page: The page to read
- *
- * On entry, the page should be locked. It will be unlocked when the page
- * has been read. If the block driver implements rw_page synchronously,
- * that will be true on exit from this function, but it need not be.
- *
- * Errors returned by this function are usually "soft", eg out of memory, or
- * queue full; callers should try a different route to read this page rather
- * than propagate an error back up the stack.
- *
- * Return: negative errno if an error occurs, 0 if submission was successful.
- */
-int bdev_read_page(struct block_device *bdev, sector_t sector,
- struct page *page)
-{
- const struct block_device_operations *ops = bdev->bd_disk->fops;
- int result = -EOPNOTSUPP;
-
- if (!ops->rw_page || bdev_get_integrity(bdev))
- return result;
-
- result = blk_queue_enter(bdev->bd_disk->queue, 0);
- if (result)
- return result;
- result = ops->rw_page(bdev, sector + get_start_sect(bdev), page,
- REQ_OP_READ);
- blk_queue_exit(bdev->bd_disk->queue);
- return result;
-}
-
-/**
- * bdev_write_page() - Start writing a page to a block device
- * @bdev: The device to write the page to
- * @sector: The offset on the device to write the page to (need not be aligned)
- * @page: The page to write
- * @wbc: The writeback_control for the write
- *
- * On entry, the page should be locked and not currently under writeback.
- * On exit, if the write started successfully, the page will be unlocked and
- * under writeback. If the write failed already (eg the driver failed to
- * queue the page to the device), the page will still be locked. If the
- * caller is a ->writepage implementation, it will need to unlock the page.
- *
- * Errors returned by this function are usually "soft", eg out of memory, or
- * queue full; callers should try a different route to write this page rather
- * than propagate an error back up the stack.
- *
- * Return: negative errno if an error occurs, 0 if submission was successful.
- */
-int bdev_write_page(struct block_device *bdev, sector_t sector,
- struct page *page, struct writeback_control *wbc)
-{
- int result;
- const struct block_device_operations *ops = bdev->bd_disk->fops;
-
- if (!ops->rw_page || bdev_get_integrity(bdev))
- return -EOPNOTSUPP;
- result = blk_queue_enter(bdev->bd_disk->queue, 0);
- if (result)
- return result;
-
- set_page_writeback(page);
- result = ops->rw_page(bdev, sector + get_start_sect(bdev), page,
- REQ_OP_WRITE);
- if (result) {
- end_page_writeback(page);
- } else {
- clean_page_buffers(page);
- unlock_page(page);
- }
- blk_queue_exit(bdev->bd_disk->queue);
- return result;
-}
-
-/*
- * pseudo-fs
- */
-
-static __cacheline_aligned_in_smp DEFINE_SPINLOCK(bdev_lock);
-static struct kmem_cache * bdev_cachep __read_mostly;
-
-static struct inode *bdev_alloc_inode(struct super_block *sb)
-{
- struct bdev_inode *ei = kmem_cache_alloc(bdev_cachep, GFP_KERNEL);
-
- if (!ei)
- return NULL;
- memset(&ei->bdev, 0, sizeof(ei->bdev));
- return &ei->vfs_inode;
-}
-
-static void bdev_free_inode(struct inode *inode)
-{
- struct block_device *bdev = I_BDEV(inode);
-
- free_percpu(bdev->bd_stats);
- kfree(bdev->bd_meta_info);
-
- if (!bdev_is_partition(bdev)) {
- if (bdev->bd_disk && bdev->bd_disk->bdi)
- bdi_put(bdev->bd_disk->bdi);
- kfree(bdev->bd_disk);
- }
-
- if (MAJOR(bdev->bd_dev) == BLOCK_EXT_MAJOR)
- blk_free_ext_minor(MINOR(bdev->bd_dev));
-
- kmem_cache_free(bdev_cachep, BDEV_I(inode));
-}
-
-static void init_once(void *data)
-{
- struct bdev_inode *ei = data;
-
- inode_init_once(&ei->vfs_inode);
-}
-
-static void bdev_evict_inode(struct inode *inode)
-{
- truncate_inode_pages_final(&inode->i_data);
- invalidate_inode_buffers(inode); /* is it needed here? */
- clear_inode(inode);
-}
-
-static const struct super_operations bdev_sops = {
- .statfs = simple_statfs,
- .alloc_inode = bdev_alloc_inode,
- .free_inode = bdev_free_inode,
- .drop_inode = generic_delete_inode,
- .evict_inode = bdev_evict_inode,
-};
-
-static int bd_init_fs_context(struct fs_context *fc)
-{
- struct pseudo_fs_context *ctx = init_pseudo(fc, BDEVFS_MAGIC);
- if (!ctx)
- return -ENOMEM;
- fc->s_iflags |= SB_I_CGROUPWB;
- ctx->ops = &bdev_sops;
- return 0;
-}
-
-static struct file_system_type bd_type = {
- .name = "bdev",
- .init_fs_context = bd_init_fs_context,
- .kill_sb = kill_anon_super,
-};
-
-struct super_block *blockdev_superblock __read_mostly;
-EXPORT_SYMBOL_GPL(blockdev_superblock);
-
-void __init bdev_cache_init(void)
-{
- int err;
- static struct vfsmount *bd_mnt;
-
- bdev_cachep = kmem_cache_create("bdev_cache", sizeof(struct bdev_inode),
- 0, (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|
- SLAB_MEM_SPREAD|SLAB_ACCOUNT|SLAB_PANIC),
- init_once);
- err = register_filesystem(&bd_type);
- if (err)
- panic("Cannot register bdev pseudo-fs");
- bd_mnt = kern_mount(&bd_type);
- if (IS_ERR(bd_mnt))
- panic("Cannot create bdev pseudo-fs");
- blockdev_superblock = bd_mnt->mnt_sb; /* For writeback */
-}
-
-struct block_device *bdev_alloc(struct gendisk *disk, u8 partno)
-{
- struct block_device *bdev;
- struct inode *inode;
-
- inode = new_inode(blockdev_superblock);
- if (!inode)
- return NULL;
- inode->i_mode = S_IFBLK;
- inode->i_rdev = 0;
- inode->i_data.a_ops = &def_blk_aops;
- mapping_set_gfp_mask(&inode->i_data, GFP_USER);
-
- bdev = I_BDEV(inode);
- mutex_init(&bdev->bd_fsfreeze_mutex);
- spin_lock_init(&bdev->bd_size_lock);
- bdev->bd_disk = disk;
- bdev->bd_partno = partno;
- bdev->bd_inode = inode;
- bdev->bd_stats = alloc_percpu(struct disk_stats);
- if (!bdev->bd_stats) {
- iput(inode);
- return NULL;
- }
- return bdev;
-}
-
-void bdev_add(struct block_device *bdev, dev_t dev)
-{
- bdev->bd_dev = dev;
- bdev->bd_inode->i_rdev = dev;
- bdev->bd_inode->i_ino = dev;
- insert_inode_hash(bdev->bd_inode);
-}
-
-long nr_blockdev_pages(void)
-{
- struct inode *inode;
- long ret = 0;
-
- spin_lock(&blockdev_superblock->s_inode_list_lock);
- list_for_each_entry(inode, &blockdev_superblock->s_inodes, i_sb_list)
- ret += inode->i_mapping->nrpages;
- spin_unlock(&blockdev_superblock->s_inode_list_lock);
-
- return ret;
-}
-
-/**
- * bd_may_claim - test whether a block device can be claimed
- * @bdev: block device of interest
- * @whole: whole block device containing @bdev, may equal @bdev
- * @holder: holder trying to claim @bdev
- *
- * Test whether @bdev can be claimed by @holder.
- *
- * CONTEXT:
- * spin_lock(&bdev_lock).
- *
- * RETURNS:
- * %true if @bdev can be claimed, %false otherwise.
- */
-static bool bd_may_claim(struct block_device *bdev, struct block_device *whole,
- void *holder)
-{
- if (bdev->bd_holder == holder)
- return true; /* already a holder */
- else if (bdev->bd_holder != NULL)
- return false; /* held by someone else */
- else if (whole == bdev)
- return true; /* is a whole device which isn't held */
-
- else if (whole->bd_holder == bd_may_claim)
- return true; /* is a partition of a device that is being partitioned */
- else if (whole->bd_holder != NULL)
- return false; /* is a partition of a held device */
- else
- return true; /* is a partition of an un-held device */
-}
-
-/**
- * bd_prepare_to_claim - claim a block device
- * @bdev: block device of interest
- * @holder: holder trying to claim @bdev
- *
- * Claim @bdev. This function fails if @bdev is already claimed by another
- * holder and waits if another claiming is in progress. return, the caller
- * has ownership of bd_claiming and bd_holder[s].
- *
- * RETURNS:
- * 0 if @bdev can be claimed, -EBUSY otherwise.
- */
-int bd_prepare_to_claim(struct block_device *bdev, void *holder)
-{
- struct block_device *whole = bdev_whole(bdev);
-
- if (WARN_ON_ONCE(!holder))
- return -EINVAL;
-retry:
- spin_lock(&bdev_lock);
- /* if someone else claimed, fail */
- if (!bd_may_claim(bdev, whole, holder)) {
- spin_unlock(&bdev_lock);
- return -EBUSY;
- }
-
- /* if claiming is already in progress, wait for it to finish */
- if (whole->bd_claiming) {
- wait_queue_head_t *wq = bit_waitqueue(&whole->bd_claiming, 0);
- DEFINE_WAIT(wait);
-
- prepare_to_wait(wq, &wait, TASK_UNINTERRUPTIBLE);
- spin_unlock(&bdev_lock);
- schedule();
- finish_wait(wq, &wait);
- goto retry;
- }
-
- /* yay, all mine */
- whole->bd_claiming = holder;
- spin_unlock(&bdev_lock);
- return 0;
-}
-EXPORT_SYMBOL_GPL(bd_prepare_to_claim); /* only for the loop driver */
-
-static void bd_clear_claiming(struct block_device *whole, void *holder)
-{
- lockdep_assert_held(&bdev_lock);
- /* tell others that we're done */
- BUG_ON(whole->bd_claiming != holder);
- whole->bd_claiming = NULL;
- wake_up_bit(&whole->bd_claiming, 0);
-}
-
-/**
- * bd_finish_claiming - finish claiming of a block device
- * @bdev: block device of interest
- * @holder: holder that has claimed @bdev
- *
- * Finish exclusive open of a block device. Mark the device as exlusively
- * open by the holder and wake up all waiters for exclusive open to finish.
- */
-static void bd_finish_claiming(struct block_device *bdev, void *holder)
-{
- struct block_device *whole = bdev_whole(bdev);
-
- spin_lock(&bdev_lock);
- BUG_ON(!bd_may_claim(bdev, whole, holder));
- /*
- * Note that for a whole device bd_holders will be incremented twice,
- * and bd_holder will be set to bd_may_claim before being set to holder
- */
- whole->bd_holders++;
- whole->bd_holder = bd_may_claim;
- bdev->bd_holders++;
- bdev->bd_holder = holder;
- bd_clear_claiming(whole, holder);
- spin_unlock(&bdev_lock);
-}
-
-/**
- * bd_abort_claiming - abort claiming of a block device
- * @bdev: block device of interest
- * @holder: holder that has claimed @bdev
- *
- * Abort claiming of a block device when the exclusive open failed. This can be
- * also used when exclusive open is not actually desired and we just needed
- * to block other exclusive openers for a while.
- */
-void bd_abort_claiming(struct block_device *bdev, void *holder)
-{
- spin_lock(&bdev_lock);
- bd_clear_claiming(bdev_whole(bdev), holder);
- spin_unlock(&bdev_lock);
-}
-EXPORT_SYMBOL(bd_abort_claiming);
-
-static void blkdev_flush_mapping(struct block_device *bdev)
-{
- WARN_ON_ONCE(bdev->bd_holders);
- sync_blockdev(bdev);
- kill_bdev(bdev);
- bdev_write_inode(bdev);
-}
-
-static int blkdev_get_whole(struct block_device *bdev, fmode_t mode)
-{
- struct gendisk *disk = bdev->bd_disk;
- int ret = 0;
-
- if (disk->fops->open) {
- ret = disk->fops->open(bdev, mode);
- if (ret) {
- /* avoid ghost partitions on a removed medium */
- if (ret == -ENOMEDIUM &&
- test_bit(GD_NEED_PART_SCAN, &disk->state))
- bdev_disk_changed(disk, true);
- return ret;
- }
- }
-
- if (!bdev->bd_openers)
- set_init_blocksize(bdev);
- if (test_bit(GD_NEED_PART_SCAN, &disk->state))
- bdev_disk_changed(disk, false);
- bdev->bd_openers++;
- return 0;;
-}
-
-static void blkdev_put_whole(struct block_device *bdev, fmode_t mode)
-{
- if (!--bdev->bd_openers)
- blkdev_flush_mapping(bdev);
- if (bdev->bd_disk->fops->release)
- bdev->bd_disk->fops->release(bdev->bd_disk, mode);
-}
-
-static int blkdev_get_part(struct block_device *part, fmode_t mode)
-{
- struct gendisk *disk = part->bd_disk;
- int ret;
-
- if (part->bd_openers)
- goto done;
-
- ret = blkdev_get_whole(bdev_whole(part), mode);
- if (ret)
- return ret;
-
- ret = -ENXIO;
- if (!bdev_nr_sectors(part))
- goto out_blkdev_put;
-
- disk->open_partitions++;
- set_init_blocksize(part);
-done:
- part->bd_openers++;
- return 0;
-
-out_blkdev_put:
- blkdev_put_whole(bdev_whole(part), mode);
- return ret;
-}
-
-static void blkdev_put_part(struct block_device *part, fmode_t mode)
-{
- struct block_device *whole = bdev_whole(part);
-
- if (--part->bd_openers)
- return;
- blkdev_flush_mapping(part);
- whole->bd_disk->open_partitions--;
- blkdev_put_whole(whole, mode);
-}
-
-struct block_device *blkdev_get_no_open(dev_t dev)
-{
- struct block_device *bdev;
- struct inode *inode;
-
- inode = ilookup(blockdev_superblock, dev);
- if (!inode) {
- blk_request_module(dev);
- inode = ilookup(blockdev_superblock, dev);
- if (!inode)
- return NULL;
- }
-
- /* switch from the inode reference to a device mode one: */
- bdev = &BDEV_I(inode)->bdev;
- if (!kobject_get_unless_zero(&bdev->bd_device.kobj))
- bdev = NULL;
- iput(inode);
-
- if (!bdev)
- return NULL;
- if ((bdev->bd_disk->flags & GENHD_FL_HIDDEN) ||
- !try_module_get(bdev->bd_disk->fops->owner)) {
- put_device(&bdev->bd_device);
- return NULL;
- }
-
- return bdev;
-}
-
-void blkdev_put_no_open(struct block_device *bdev)
-{
- module_put(bdev->bd_disk->fops->owner);
- put_device(&bdev->bd_device);
-}
-
-/**
- * blkdev_get_by_dev - open a block device by device number
- * @dev: device number of block device to open
- * @mode: FMODE_* mask
- * @holder: exclusive holder identifier
- *
- * Open the block device described by device number @dev. If @mode includes
- * %FMODE_EXCL, the block device is opened with exclusive access. Specifying
- * %FMODE_EXCL with a %NULL @holder is invalid. Exclusive opens may nest for
- * the same @holder.
- *
- * Use this interface ONLY if you really do not have anything better - i.e. when
- * you are behind a truly sucky interface and all you are given is a device
- * number. Everything else should use blkdev_get_by_path().
- *
- * CONTEXT:
- * Might sleep.
- *
- * RETURNS:
- * Reference to the block_device on success, ERR_PTR(-errno) on failure.
- */
-struct block_device *blkdev_get_by_dev(dev_t dev, fmode_t mode, void *holder)
-{
- bool unblock_events = true;
- struct block_device *bdev;
- struct gendisk *disk;
- int ret;
-
- ret = devcgroup_check_permission(DEVCG_DEV_BLOCK,
- MAJOR(dev), MINOR(dev),
- ((mode & FMODE_READ) ? DEVCG_ACC_READ : 0) |
- ((mode & FMODE_WRITE) ? DEVCG_ACC_WRITE : 0));
- if (ret)
- return ERR_PTR(ret);
-
- bdev = blkdev_get_no_open(dev);
- if (!bdev)
- return ERR_PTR(-ENXIO);
- disk = bdev->bd_disk;
-
- if (mode & FMODE_EXCL) {
- ret = bd_prepare_to_claim(bdev, holder);
- if (ret)
- goto put_blkdev;
- }
-
- disk_block_events(disk);
-
- mutex_lock(&disk->open_mutex);
- ret = -ENXIO;
- if (!disk_live(disk))
- goto abort_claiming;
- if (bdev_is_partition(bdev))
- ret = blkdev_get_part(bdev, mode);
- else
- ret = blkdev_get_whole(bdev, mode);
- if (ret)
- goto abort_claiming;
- if (mode & FMODE_EXCL) {
- bd_finish_claiming(bdev, holder);
-
- /*
- * Block event polling for write claims if requested. Any write
- * holder makes the write_holder state stick until all are
- * released. This is good enough and tracking individual
- * writeable reference is too fragile given the way @mode is
- * used in blkdev_get/put().
- */
- if ((mode & FMODE_WRITE) && !bdev->bd_write_holder &&
- (disk->flags & GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE)) {
- bdev->bd_write_holder = true;
- unblock_events = false;
- }
- }
- mutex_unlock(&disk->open_mutex);
-
- if (unblock_events)
- disk_unblock_events(disk);
- return bdev;
-
-abort_claiming:
- if (mode & FMODE_EXCL)
- bd_abort_claiming(bdev, holder);
- mutex_unlock(&disk->open_mutex);
- disk_unblock_events(disk);
-put_blkdev:
- blkdev_put_no_open(bdev);
- return ERR_PTR(ret);
-}
-EXPORT_SYMBOL(blkdev_get_by_dev);
-
-/**
- * blkdev_get_by_path - open a block device by name
- * @path: path to the block device to open
- * @mode: FMODE_* mask
- * @holder: exclusive holder identifier
- *
- * Open the block device described by the device file at @path. If @mode
- * includes %FMODE_EXCL, the block device is opened with exclusive access.
- * Specifying %FMODE_EXCL with a %NULL @holder is invalid. Exclusive opens may
- * nest for the same @holder.
- *
- * CONTEXT:
- * Might sleep.
- *
- * RETURNS:
- * Reference to the block_device on success, ERR_PTR(-errno) on failure.
- */
-struct block_device *blkdev_get_by_path(const char *path, fmode_t mode,
- void *holder)
-{
- struct block_device *bdev;
- dev_t dev;
- int error;
-
- error = lookup_bdev(path, &dev);
- if (error)
- return ERR_PTR(error);
-
- bdev = blkdev_get_by_dev(dev, mode, holder);
- if (!IS_ERR(bdev) && (mode & FMODE_WRITE) && bdev_read_only(bdev)) {
- blkdev_put(bdev, mode);
- return ERR_PTR(-EACCES);
- }
-
- return bdev;
-}
-EXPORT_SYMBOL(blkdev_get_by_path);
-
-static int blkdev_open(struct inode * inode, struct file * filp)
-{
- struct block_device *bdev;
-
- /*
- * Preserve backwards compatibility and allow large file access
- * even if userspace doesn't ask for it explicitly. Some mkfs
- * binary needs it. We might want to drop this workaround
- * during an unstable branch.
- */
- filp->f_flags |= O_LARGEFILE;
-
- filp->f_mode |= FMODE_NOWAIT | FMODE_BUF_RASYNC;
-
- if (filp->f_flags & O_NDELAY)
- filp->f_mode |= FMODE_NDELAY;
- if (filp->f_flags & O_EXCL)
- filp->f_mode |= FMODE_EXCL;
- if ((filp->f_flags & O_ACCMODE) == 3)
- filp->f_mode |= FMODE_WRITE_IOCTL;
-
- bdev = blkdev_get_by_dev(inode->i_rdev, filp->f_mode, filp);
- if (IS_ERR(bdev))
- return PTR_ERR(bdev);
- filp->f_mapping = bdev->bd_inode->i_mapping;
- filp->f_wb_err = filemap_sample_wb_err(filp->f_mapping);
- return 0;
-}
-
-void blkdev_put(struct block_device *bdev, fmode_t mode)
-{
- struct gendisk *disk = bdev->bd_disk;
-
- /*
- * Sync early if it looks like we're the last one. If someone else
- * opens the block device between now and the decrement of bd_openers
- * then we did a sync that we didn't need to, but that's not the end
- * of the world and we want to avoid long (could be several minute)
- * syncs while holding the mutex.
- */
- if (bdev->bd_openers == 1)
- sync_blockdev(bdev);
-
- mutex_lock(&disk->open_mutex);
- if (mode & FMODE_EXCL) {
- struct block_device *whole = bdev_whole(bdev);
- bool bdev_free;
-
- /*
- * Release a claim on the device. The holder fields
- * are protected with bdev_lock. open_mutex is to
- * synchronize disk_holder unlinking.
- */
- spin_lock(&bdev_lock);
-
- WARN_ON_ONCE(--bdev->bd_holders < 0);
- WARN_ON_ONCE(--whole->bd_holders < 0);
-
- if ((bdev_free = !bdev->bd_holders))
- bdev->bd_holder = NULL;
- if (!whole->bd_holders)
- whole->bd_holder = NULL;
-
- spin_unlock(&bdev_lock);
-
- /*
- * If this was the last claim, remove holder link and
- * unblock evpoll if it was a write holder.
- */
- if (bdev_free && bdev->bd_write_holder) {
- disk_unblock_events(disk);
- bdev->bd_write_holder = false;
- }
- }
-
- /*
- * Trigger event checking and tell drivers to flush MEDIA_CHANGE
- * event. This is to ensure detection of media removal commanded
- * from userland - e.g. eject(1).
- */
- disk_flush_events(disk, DISK_EVENT_MEDIA_CHANGE);
-
- if (bdev_is_partition(bdev))
- blkdev_put_part(bdev, mode);
- else
- blkdev_put_whole(bdev, mode);
- mutex_unlock(&disk->open_mutex);
-
- blkdev_put_no_open(bdev);
-}
-EXPORT_SYMBOL(blkdev_put);
-
-static int blkdev_close(struct inode * inode, struct file * filp)
-{
- struct block_device *bdev = I_BDEV(bdev_file_inode(filp));
- blkdev_put(bdev, filp->f_mode);
- return 0;
-}
-
-static long block_ioctl(struct file *file, unsigned cmd, unsigned long arg)
-{
- struct block_device *bdev = I_BDEV(bdev_file_inode(file));
- fmode_t mode = file->f_mode;
-
- /*
- * O_NDELAY can be altered using fcntl(.., F_SETFL, ..), so we have
- * to updated it before every ioctl.
- */
- if (file->f_flags & O_NDELAY)
- mode |= FMODE_NDELAY;
- else
- mode &= ~FMODE_NDELAY;
-
- return blkdev_ioctl(bdev, mode, cmd, arg);
-}
-
-/*
- * Write data to the block device. Only intended for the block device itself
- * and the raw driver which basically is a fake block device.
- *
- * Does not take i_mutex for the write and thus is not for general purpose
- * use.
- */
-static ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from)
-{
- struct file *file = iocb->ki_filp;
- struct inode *bd_inode = bdev_file_inode(file);
- loff_t size = i_size_read(bd_inode);
- struct blk_plug plug;
- size_t shorted = 0;
- ssize_t ret;
-
- if (bdev_read_only(I_BDEV(bd_inode)))
- return -EPERM;
-
- if (IS_SWAPFILE(bd_inode) && !is_hibernate_resume_dev(bd_inode->i_rdev))
- return -ETXTBSY;
-
- if (!iov_iter_count(from))
- return 0;
-
- if (iocb->ki_pos >= size)
- return -ENOSPC;
-
- if ((iocb->ki_flags & (IOCB_NOWAIT | IOCB_DIRECT)) == IOCB_NOWAIT)
- return -EOPNOTSUPP;
-
- size -= iocb->ki_pos;
- if (iov_iter_count(from) > size) {
- shorted = iov_iter_count(from) - size;
- iov_iter_truncate(from, size);
- }
-
- blk_start_plug(&plug);
- ret = __generic_file_write_iter(iocb, from);
- if (ret > 0)
- ret = generic_write_sync(iocb, ret);
- iov_iter_reexpand(from, iov_iter_count(from) + shorted);
- blk_finish_plug(&plug);
- return ret;
-}
-
-static ssize_t blkdev_read_iter(struct kiocb *iocb, struct iov_iter *to)
-{
- struct file *file = iocb->ki_filp;
- struct inode *bd_inode = bdev_file_inode(file);
- loff_t size = i_size_read(bd_inode);
- loff_t pos = iocb->ki_pos;
- size_t shorted = 0;
- ssize_t ret;
-
- if (pos >= size)
- return 0;
-
- size -= pos;
- if (iov_iter_count(to) > size) {
- shorted = iov_iter_count(to) - size;
- iov_iter_truncate(to, size);
- }
-
- ret = generic_file_read_iter(iocb, to);
- iov_iter_reexpand(to, iov_iter_count(to) + shorted);
- return ret;
-}
-
-static int blkdev_writepages(struct address_space *mapping,
- struct writeback_control *wbc)
-{
- return generic_writepages(mapping, wbc);
-}
-
-static const struct address_space_operations def_blk_aops = {
- .set_page_dirty = __set_page_dirty_buffers,
- .readpage = blkdev_readpage,
- .readahead = blkdev_readahead,
- .writepage = blkdev_writepage,
- .write_begin = blkdev_write_begin,
- .write_end = blkdev_write_end,
- .writepages = blkdev_writepages,
- .direct_IO = blkdev_direct_IO,
- .migratepage = buffer_migrate_page_norefs,
- .is_dirty_writeback = buffer_check_dirty_writeback,
-};
-
-#define BLKDEV_FALLOC_FL_SUPPORTED \
- (FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE | \
- FALLOC_FL_ZERO_RANGE | FALLOC_FL_NO_HIDE_STALE)
-
-static long blkdev_fallocate(struct file *file, int mode, loff_t start,
- loff_t len)
-{
- struct block_device *bdev = I_BDEV(bdev_file_inode(file));
- loff_t end = start + len - 1;
- loff_t isize;
- int error;
-
- /* Fail if we don't recognize the flags. */
- if (mode & ~BLKDEV_FALLOC_FL_SUPPORTED)
- return -EOPNOTSUPP;
-
- /* Don't go off the end of the device. */
- isize = i_size_read(bdev->bd_inode);
- if (start >= isize)
- return -EINVAL;
- if (end >= isize) {
- if (mode & FALLOC_FL_KEEP_SIZE) {
- len = isize - start;
- end = start + len - 1;
- } else
- return -EINVAL;
- }
-
- /*
- * Don't allow IO that isn't aligned to logical block size.
- */
- if ((start | len) & (bdev_logical_block_size(bdev) - 1))
- return -EINVAL;
-
- /* Invalidate the page cache, including dirty pages. */
- error = truncate_bdev_range(bdev, file->f_mode, start, end);
- if (error)
- return error;
-
- switch (mode) {
- case FALLOC_FL_ZERO_RANGE:
- case FALLOC_FL_ZERO_RANGE | FALLOC_FL_KEEP_SIZE:
- error = blkdev_issue_zeroout(bdev, start >> 9, len >> 9,
- GFP_KERNEL, BLKDEV_ZERO_NOUNMAP);
- break;
- case FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE:
- error = blkdev_issue_zeroout(bdev, start >> 9, len >> 9,
- GFP_KERNEL, BLKDEV_ZERO_NOFALLBACK);
- break;
- case FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE | FALLOC_FL_NO_HIDE_STALE:
- error = blkdev_issue_discard(bdev, start >> 9, len >> 9,
- GFP_KERNEL, 0);
- break;
- default:
- return -EOPNOTSUPP;
- }
- if (error)
- return error;
-
- /*
- * Invalidate the page cache again; if someone wandered in and dirtied
- * a page, we just discard it - userspace has no way of knowing whether
- * the write happened before or after discard completing...
- */
- return truncate_bdev_range(bdev, file->f_mode, start, end);
-}
-
-const struct file_operations def_blk_fops = {
- .open = blkdev_open,
- .release = blkdev_close,
- .llseek = block_llseek,
- .read_iter = blkdev_read_iter,
- .write_iter = blkdev_write_iter,
- .iopoll = blkdev_iopoll,
- .mmap = generic_file_mmap,
- .fsync = blkdev_fsync,
- .unlocked_ioctl = block_ioctl,
-#ifdef CONFIG_COMPAT
- .compat_ioctl = compat_blkdev_ioctl,
-#endif
- .splice_read = generic_file_splice_read,
- .splice_write = iter_file_splice_write,
- .fallocate = blkdev_fallocate,
-};
-
-/**
- * lookup_bdev - lookup a struct block_device by name
- * @pathname: special file representing the block device
- * @dev: return value of the block device's dev_t
- *
- * Get a reference to the blockdevice at @pathname in the current
- * namespace if possible and return it. Return ERR_PTR(error)
- * otherwise.
- */
-int lookup_bdev(const char *pathname, dev_t *dev)
-{
- struct inode *inode;
- struct path path;
- int error;
-
- if (!pathname || !*pathname)
- return -EINVAL;
-
- error = kern_path(pathname, LOOKUP_FOLLOW, &path);
- if (error)
- return error;
-
- inode = d_backing_inode(path.dentry);
- error = -ENOTBLK;
- if (!S_ISBLK(inode->i_mode))
- goto out_path_put;
- error = -EACCES;
- if (!may_open_dev(&path))
- goto out_path_put;
-
- *dev = inode->i_rdev;
- error = 0;
-out_path_put:
- path_put(&path);
- return error;
-}
-EXPORT_SYMBOL(lookup_bdev);
-
-int __invalidate_device(struct block_device *bdev, bool kill_dirty)
-{
- struct super_block *sb = get_super(bdev);
- int res = 0;
-
- if (sb) {
- /*
- * no need to lock the super, get_super holds the
- * read mutex so the filesystem cannot go away
- * under us (->put_super runs with the write lock
- * hold).
- */
- shrink_dcache_sb(sb);
- res = invalidate_inodes(sb, kill_dirty);
- drop_super(sb);
- }
- invalidate_bdev(bdev);
- return res;
-}
-EXPORT_SYMBOL(__invalidate_device);
-
-void iterate_bdevs(void (*func)(struct block_device *, void *), void *arg)
-{
- struct inode *inode, *old_inode = NULL;
-
- spin_lock(&blockdev_superblock->s_inode_list_lock);
- list_for_each_entry(inode, &blockdev_superblock->s_inodes, i_sb_list) {
- struct address_space *mapping = inode->i_mapping;
- struct block_device *bdev;
-
- spin_lock(&inode->i_lock);
- if (inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW) ||
- mapping->nrpages == 0) {
- spin_unlock(&inode->i_lock);
- continue;
- }
- __iget(inode);
- spin_unlock(&inode->i_lock);
- spin_unlock(&blockdev_superblock->s_inode_list_lock);
- /*
- * We hold a reference to 'inode' so it couldn't have been
- * removed from s_inodes list while we dropped the
- * s_inode_list_lock We cannot iput the inode now as we can
- * be holding the last reference and we cannot iput it under
- * s_inode_list_lock. So we keep the reference and iput it
- * later.
- */
- iput(old_inode);
- old_inode = inode;
- bdev = I_BDEV(inode);
-
- mutex_lock(&bdev->bd_disk->open_mutex);
- if (bdev->bd_openers)
- func(bdev, arg);
- mutex_unlock(&bdev->bd_disk->open_mutex);
-
- spin_lock(&blockdev_superblock->s_inode_list_lock);
- }
- spin_unlock(&blockdev_superblock->s_inode_list_lock);
- iput(old_inode);
-}
struct pipe_inode_info;
/*
- * block_dev.c
+ * block/bdev.c
*/
#ifdef CONFIG_BLOCK
extern void __init bdev_cache_init(void);
projects / linux-2.6-microblaze.git / commitdiff