* Copyright (C) 2001 Andrea Arcangeli <andrea@suse.de> SuSE
*/
-#include <linux/config.h>
#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/devfs_fs_kernel.h>
#include <linux/smp_lock.h>
#include <linux/highmem.h>
#include <linux/blkdev.h>
#include <linux/module.h>
#include <linux/blkpg.h>
#include <linux/buffer_head.h>
+#include <linux/writeback.h>
#include <linux/mpage.h>
#include <linux/mount.h>
#include <linux/uio.h>
#include <linux/namei.h>
#include <asm/uaccess.h>
+#include "internal.h"
struct bdev_inode {
struct block_device bdev;
int sb_set_blocksize(struct super_block *sb, int size)
{
- int bits = 9; /* 2^9 = 512 */
-
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;
- for (size >>= 10; size; size >>= 1)
- ++bits;
- sb->s_blocksize_bits = bits;
+ sb->s_blocksize_bits = blksize_bits(size);
return sb->s_blocksize;
}
static int
blkdev_get_blocks(struct inode *inode, sector_t iblock,
- unsigned long max_blocks, struct buffer_head *bh, int create)
+ struct buffer_head *bh, int create)
{
sector_t end_block = max_block(I_BDEV(inode));
+ unsigned long max_blocks = bh->b_size >> inode->i_blkbits;
if ((iblock + max_blocks) > end_block) {
max_blocks = end_block - iblock;
iov, offset, nr_segs, blkdev_get_blocks, NULL);
}
+#if 0
+static int blk_end_aio(struct bio *bio, unsigned int bytes_done, int error)
+{
+ struct kiocb *iocb = bio->bi_private;
+ atomic_t *bio_count = &iocb->ki_bio_count;
+
+ if (bio_data_dir(bio) == READ)
+ bio_check_pages_dirty(bio);
+ else {
+ bio_release_pages(bio);
+ bio_put(bio);
+ }
+
+ /* iocb->ki_nbytes stores error code from LLDD */
+ if (error)
+ iocb->ki_nbytes = -EIO;
+
+ if (atomic_dec_and_test(bio_count)) {
+ if ((long)iocb->ki_nbytes < 0)
+ aio_complete(iocb, iocb->ki_nbytes, 0);
+ else
+ aio_complete(iocb, iocb->ki_left, 0);
+ }
+
+ return 0;
+}
+
+#define VEC_SIZE 16
+struct pvec {
+ unsigned short nr;
+ unsigned short idx;
+ struct page *page[VEC_SIZE];
+};
+
+#define PAGES_SPANNED(addr, len) \
+ (DIV_ROUND_UP((addr) + (len), PAGE_SIZE) - (addr) / PAGE_SIZE);
+
+/*
+ * get page pointer for user addr, we internally cache struct page array for
+ * (addr, count) range in pvec to avoid frequent call to get_user_pages. If
+ * internal page list is exhausted, a batch count of up to VEC_SIZE is used
+ * to get next set of page struct.
+ */
+static struct page *blk_get_page(unsigned long addr, size_t count, int rw,
+ struct pvec *pvec)
+{
+ int ret, nr_pages;
+ if (pvec->idx == pvec->nr) {
+ nr_pages = PAGES_SPANNED(addr, count);
+ nr_pages = min(nr_pages, VEC_SIZE);
+ down_read(¤t->mm->mmap_sem);
+ ret = get_user_pages(current, current->mm, addr, nr_pages,
+ rw == READ, 0, pvec->page, NULL);
+ up_read(¤t->mm->mmap_sem);
+ if (ret < 0)
+ return ERR_PTR(ret);
+ pvec->nr = ret;
+ pvec->idx = 0;
+ }
+ return pvec->page[pvec->idx++];
+}
+
+/* return a page back to pvec array */
+static void blk_unget_page(struct page *page, struct pvec *pvec)
+{
+ pvec->page[--pvec->idx] = page;
+}
+
+static ssize_t
+blkdev_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov,
+ loff_t pos, unsigned long nr_segs)
+{
+ struct inode *inode = iocb->ki_filp->f_mapping->host;
+ unsigned blkbits = blksize_bits(bdev_hardsect_size(I_BDEV(inode)));
+ unsigned blocksize_mask = (1 << blkbits) - 1;
+ unsigned long seg = 0; /* iov segment iterator */
+ unsigned long nvec; /* number of bio vec needed */
+ unsigned long cur_off; /* offset into current page */
+ unsigned long cur_len; /* I/O len of current page, up to PAGE_SIZE */
+
+ unsigned long addr; /* user iovec address */
+ size_t count; /* user iovec len */
+ size_t nbytes = iocb->ki_nbytes = iocb->ki_left; /* total xfer size */
+ loff_t size; /* size of block device */
+ struct bio *bio;
+ atomic_t *bio_count = &iocb->ki_bio_count;
+ struct page *page;
+ struct pvec pvec;
+
+ pvec.nr = 0;
+ pvec.idx = 0;
+
+ if (pos & blocksize_mask)
+ return -EINVAL;
+
+ size = i_size_read(inode);
+ if (pos + nbytes > size) {
+ nbytes = size - pos;
+ iocb->ki_left = nbytes;
+ }
+
+ /*
+ * check first non-zero iov alignment, the remaining
+ * iov alignment is checked inside bio loop below.
+ */
+ do {
+ addr = (unsigned long) iov[seg].iov_base;
+ count = min(iov[seg].iov_len, nbytes);
+ if (addr & blocksize_mask || count & blocksize_mask)
+ return -EINVAL;
+ } while (!count && ++seg < nr_segs);
+ atomic_set(bio_count, 1);
+
+ while (nbytes) {
+ /* roughly estimate number of bio vec needed */
+ nvec = (nbytes + PAGE_SIZE - 1) / PAGE_SIZE;
+ nvec = max(nvec, nr_segs - seg);
+ nvec = min(nvec, (unsigned long) BIO_MAX_PAGES);
+
+ /* bio_alloc should not fail with GFP_KERNEL flag */
+ bio = bio_alloc(GFP_KERNEL, nvec);
+ bio->bi_bdev = I_BDEV(inode);
+ bio->bi_end_io = blk_end_aio;
+ bio->bi_private = iocb;
+ bio->bi_sector = pos >> blkbits;
+same_bio:
+ cur_off = addr & ~PAGE_MASK;
+ cur_len = PAGE_SIZE - cur_off;
+ if (count < cur_len)
+ cur_len = count;
+
+ page = blk_get_page(addr, count, rw, &pvec);
+ if (unlikely(IS_ERR(page)))
+ goto backout;
+
+ if (bio_add_page(bio, page, cur_len, cur_off)) {
+ pos += cur_len;
+ addr += cur_len;
+ count -= cur_len;
+ nbytes -= cur_len;
+
+ if (count)
+ goto same_bio;
+ while (++seg < nr_segs) {
+ addr = (unsigned long) iov[seg].iov_base;
+ count = iov[seg].iov_len;
+ if (!count)
+ continue;
+ if (unlikely(addr & blocksize_mask ||
+ count & blocksize_mask)) {
+ page = ERR_PTR(-EINVAL);
+ goto backout;
+ }
+ count = min(count, nbytes);
+ goto same_bio;
+ }
+ } else {
+ blk_unget_page(page, &pvec);
+ }
+
+ /* bio is ready, submit it */
+ if (rw == READ)
+ bio_set_pages_dirty(bio);
+ atomic_inc(bio_count);
+ submit_bio(rw, bio);
+ }
+
+completion:
+ iocb->ki_left -= nbytes;
+ nbytes = iocb->ki_left;
+ iocb->ki_pos += nbytes;
+
+ blk_run_address_space(inode->i_mapping);
+ if (atomic_dec_and_test(bio_count))
+ aio_complete(iocb, nbytes, 0);
+
+ return -EIOCBQUEUED;
+
+backout:
+ /*
+ * back out nbytes count constructed so far for this bio,
+ * we will throw away current bio.
+ */
+ nbytes += bio->bi_size;
+ bio_release_pages(bio);
+ bio_put(bio);
+
+ /*
+ * if no bio was submmitted, return the error code.
+ * otherwise, proceed with pending I/O completion.
+ */
+ if (atomic_read(bio_count) == 1)
+ return PTR_ERR(page);
+ goto completion;
+}
+#endif
+
static int blkdev_writepage(struct page *page, struct writeback_control *wbc)
{
return block_write_full_page(page, blkdev_get_block, wbc);
/*
* private llseek:
- * for a block special file file->f_dentry->d_inode->i_size is zero
+ * for a block special file file->f_path.dentry->d_inode->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 origin)
*/
static __cacheline_aligned_in_smp DEFINE_SPINLOCK(bdev_lock);
-static kmem_cache_t * bdev_cachep;
+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, SLAB_KERNEL);
+ struct bdev_inode *ei = kmem_cache_alloc(bdev_cachep, GFP_KERNEL);
if (!ei)
return NULL;
return &ei->vfs_inode;
kmem_cache_free(bdev_cachep, bdi);
}
-static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags)
+static void init_once(void * foo, struct kmem_cache * cachep, unsigned long flags)
{
struct bdev_inode *ei = (struct bdev_inode *) foo;
struct block_device *bdev = &ei->bdev;
SLAB_CTOR_CONSTRUCTOR)
{
memset(bdev, 0, sizeof(*bdev));
- sema_init(&bdev->bd_sem, 1);
+ mutex_init(&bdev->bd_mutex);
sema_init(&bdev->bd_mount_sem, 1);
INIT_LIST_HEAD(&bdev->bd_inodes);
INIT_LIST_HEAD(&bdev->bd_list);
+#ifdef CONFIG_SYSFS
+ INIT_LIST_HEAD(&bdev->bd_holder_list);
+#endif
inode_init_once(&ei->vfs_inode);
}
}
.clear_inode = bdev_clear_inode,
};
-static struct super_block *bd_get_sb(struct file_system_type *fs_type,
- int flags, const char *dev_name, void *data)
+static int bd_get_sb(struct file_system_type *fs_type,
+ int flags, const char *dev_name, void *data, struct vfsmount *mnt)
{
- return get_sb_pseudo(fs_type, "bdev:", &bdev_sops, 0x62646576);
+ return get_sb_pseudo(fs_type, "bdev:", &bdev_sops, 0x62646576, mnt);
}
static struct file_system_type bd_type = {
.kill_sb = kill_anon_super,
};
-static struct vfsmount *bd_mnt;
+static struct vfsmount *bd_mnt __read_mostly;
struct super_block *blockdev_superblock;
void __init bdev_cache_init(void)
{
int err;
bdev_cachep = kmem_cache_create("bdev_cache", sizeof(struct bdev_inode),
- 0, SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|SLAB_PANIC,
+ 0, (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|
+ SLAB_MEM_SPREAD|SLAB_PANIC),
init_once, NULL);
err = register_filesystem(&bd_type);
if (err)
static struct block_device *bd_acquire(struct inode *inode)
{
struct block_device *bdev;
+
spin_lock(&bdev_lock);
bdev = inode->i_bdev;
- if (bdev && igrab(bdev->bd_inode)) {
+ if (bdev) {
+ atomic_inc(&bdev->bd_inode->i_count);
spin_unlock(&bdev_lock);
return bdev;
}
spin_unlock(&bdev_lock);
+
bdev = bdget(inode->i_rdev);
if (bdev) {
spin_lock(&bdev_lock);
- if (inode->i_bdev)
- __bd_forget(inode);
- inode->i_bdev = bdev;
- inode->i_mapping = bdev->bd_inode->i_mapping;
- list_add(&inode->i_devices, &bdev->bd_inodes);
+ if (!inode->i_bdev) {
+ /*
+ * We take an additional bd_inode->i_count for inode,
+ * and it's released in clear_inode() of inode.
+ * So, we can access it via ->i_mapping always
+ * without igrab().
+ */
+ atomic_inc(&bdev->bd_inode->i_count);
+ inode->i_bdev = bdev;
+ inode->i_mapping = bdev->bd_inode->i_mapping;
+ list_add(&inode->i_devices, &bdev->bd_inodes);
+ }
spin_unlock(&bdev_lock);
}
return bdev;
void bd_forget(struct inode *inode)
{
+ struct block_device *bdev = NULL;
+
spin_lock(&bdev_lock);
- if (inode->i_bdev)
+ if (inode->i_bdev) {
+ if (inode->i_sb != blockdev_superblock)
+ bdev = inode->i_bdev;
__bd_forget(inode);
+ }
spin_unlock(&bdev_lock);
+
+ if (bdev)
+ iput(bdev->bd_inode);
}
int bd_claim(struct block_device *bdev, void *holder)
EXPORT_SYMBOL(bd_release);
+#ifdef CONFIG_SYSFS
+/*
+ * Functions for bd_claim_by_kobject / bd_release_from_kobject
+ *
+ * If a kobject is passed to bd_claim_by_kobject()
+ * and the kobject has a parent directory,
+ * following symlinks are created:
+ * o from the kobject to the claimed bdev
+ * o from "holders" directory of the bdev to the parent of the kobject
+ * bd_release_from_kobject() removes these symlinks.
+ *
+ * Example:
+ * If /dev/dm-0 maps to /dev/sda, kobject corresponding to
+ * /sys/block/dm-0/slaves is passed to bd_claim_by_kobject(), then:
+ * /sys/block/dm-0/slaves/sda --> /sys/block/sda
+ * /sys/block/sda/holders/dm-0 --> /sys/block/dm-0
+ */
+
+static struct kobject *bdev_get_kobj(struct block_device *bdev)
+{
+ if (bdev->bd_contains != bdev)
+ return kobject_get(&bdev->bd_part->kobj);
+ else
+ return kobject_get(&bdev->bd_disk->kobj);
+}
+
+static struct kobject *bdev_get_holder(struct block_device *bdev)
+{
+ if (bdev->bd_contains != bdev)
+ return kobject_get(bdev->bd_part->holder_dir);
+ else
+ return kobject_get(bdev->bd_disk->holder_dir);
+}
+
+static int add_symlink(struct kobject *from, struct kobject *to)
+{
+ if (!from || !to)
+ return 0;
+ return sysfs_create_link(from, to, kobject_name(to));
+}
+
+static void del_symlink(struct kobject *from, struct kobject *to)
+{
+ if (!from || !to)
+ return;
+ sysfs_remove_link(from, kobject_name(to));
+}
+
+/*
+ * 'struct bd_holder' contains pointers to kobjects symlinked by
+ * bd_claim_by_kobject.
+ * It's connected to bd_holder_list which is protected by bdev->bd_sem.
+ */
+struct bd_holder {
+ struct list_head list; /* chain of holders of the bdev */
+ int count; /* references from the holder */
+ struct kobject *sdir; /* holder object, e.g. "/block/dm-0/slaves" */
+ struct kobject *hdev; /* e.g. "/block/dm-0" */
+ struct kobject *hdir; /* e.g. "/block/sda/holders" */
+ struct kobject *sdev; /* e.g. "/block/sda" */
+};
+
+/*
+ * Get references of related kobjects at once.
+ * Returns 1 on success. 0 on failure.
+ *
+ * Should call bd_holder_release_dirs() after successful use.
+ */
+static int bd_holder_grab_dirs(struct block_device *bdev,
+ struct bd_holder *bo)
+{
+ if (!bdev || !bo)
+ return 0;
+
+ bo->sdir = kobject_get(bo->sdir);
+ if (!bo->sdir)
+ return 0;
+
+ bo->hdev = kobject_get(bo->sdir->parent);
+ if (!bo->hdev)
+ goto fail_put_sdir;
+
+ bo->sdev = bdev_get_kobj(bdev);
+ if (!bo->sdev)
+ goto fail_put_hdev;
+
+ bo->hdir = bdev_get_holder(bdev);
+ if (!bo->hdir)
+ goto fail_put_sdev;
+
+ return 1;
+
+fail_put_sdev:
+ kobject_put(bo->sdev);
+fail_put_hdev:
+ kobject_put(bo->hdev);
+fail_put_sdir:
+ kobject_put(bo->sdir);
+
+ return 0;
+}
+
+/* Put references of related kobjects at once. */
+static void bd_holder_release_dirs(struct bd_holder *bo)
+{
+ kobject_put(bo->hdir);
+ kobject_put(bo->sdev);
+ kobject_put(bo->hdev);
+ kobject_put(bo->sdir);
+}
+
+static struct bd_holder *alloc_bd_holder(struct kobject *kobj)
+{
+ struct bd_holder *bo;
+
+ bo = kzalloc(sizeof(*bo), GFP_KERNEL);
+ if (!bo)
+ return NULL;
+
+ bo->count = 1;
+ bo->sdir = kobj;
+
+ return bo;
+}
+
+static void free_bd_holder(struct bd_holder *bo)
+{
+ kfree(bo);
+}
+
+/**
+ * find_bd_holder - find matching struct bd_holder from the block device
+ *
+ * @bdev: struct block device to be searched
+ * @bo: target struct bd_holder
+ *
+ * Returns matching entry with @bo in @bdev->bd_holder_list.
+ * If found, increment the reference count and return the pointer.
+ * If not found, returns NULL.
+ */
+static struct bd_holder *find_bd_holder(struct block_device *bdev,
+ struct bd_holder *bo)
+{
+ struct bd_holder *tmp;
+
+ list_for_each_entry(tmp, &bdev->bd_holder_list, list)
+ if (tmp->sdir == bo->sdir) {
+ tmp->count++;
+ return tmp;
+ }
+
+ return NULL;
+}
+
+/**
+ * add_bd_holder - create sysfs symlinks for bd_claim() relationship
+ *
+ * @bdev: block device to be bd_claimed
+ * @bo: preallocated and initialized by alloc_bd_holder()
+ *
+ * Add @bo to @bdev->bd_holder_list, create symlinks.
+ *
+ * Returns 0 if symlinks are created.
+ * Returns -ve if something fails.
+ */
+static int add_bd_holder(struct block_device *bdev, struct bd_holder *bo)
+{
+ int ret;
+
+ if (!bo)
+ return -EINVAL;
+
+ if (!bd_holder_grab_dirs(bdev, bo))
+ return -EBUSY;
+
+ ret = add_symlink(bo->sdir, bo->sdev);
+ if (ret == 0) {
+ ret = add_symlink(bo->hdir, bo->hdev);
+ if (ret)
+ del_symlink(bo->sdir, bo->sdev);
+ }
+ if (ret == 0)
+ list_add_tail(&bo->list, &bdev->bd_holder_list);
+ return ret;
+}
+
+/**
+ * del_bd_holder - delete sysfs symlinks for bd_claim() relationship
+ *
+ * @bdev: block device to be bd_claimed
+ * @kobj: holder's kobject
+ *
+ * If there is matching entry with @kobj in @bdev->bd_holder_list
+ * and no other bd_claim() from the same kobject,
+ * remove the struct bd_holder from the list, delete symlinks for it.
+ *
+ * Returns a pointer to the struct bd_holder when it's removed from the list
+ * and ready to be freed.
+ * Returns NULL if matching claim isn't found or there is other bd_claim()
+ * by the same kobject.
+ */
+static struct bd_holder *del_bd_holder(struct block_device *bdev,
+ struct kobject *kobj)
+{
+ struct bd_holder *bo;
+
+ list_for_each_entry(bo, &bdev->bd_holder_list, list) {
+ if (bo->sdir == kobj) {
+ bo->count--;
+ BUG_ON(bo->count < 0);
+ if (!bo->count) {
+ list_del(&bo->list);
+ del_symlink(bo->sdir, bo->sdev);
+ del_symlink(bo->hdir, bo->hdev);
+ bd_holder_release_dirs(bo);
+ return bo;
+ }
+ break;
+ }
+ }
+
+ return NULL;
+}
+
+/**
+ * bd_claim_by_kobject - bd_claim() with additional kobject signature
+ *
+ * @bdev: block device to be claimed
+ * @holder: holder's signature
+ * @kobj: holder's kobject
+ *
+ * Do bd_claim() and if it succeeds, create sysfs symlinks between
+ * the bdev and the holder's kobject.
+ * Use bd_release_from_kobject() when relesing the claimed bdev.
+ *
+ * Returns 0 on success. (same as bd_claim())
+ * Returns errno on failure.
+ */
+static int bd_claim_by_kobject(struct block_device *bdev, void *holder,
+ struct kobject *kobj)
+{
+ int res;
+ struct bd_holder *bo, *found;
+
+ if (!kobj)
+ return -EINVAL;
+
+ bo = alloc_bd_holder(kobj);
+ if (!bo)
+ return -ENOMEM;
+
+ mutex_lock(&bdev->bd_mutex);
+ res = bd_claim(bdev, holder);
+ if (res == 0) {
+ found = find_bd_holder(bdev, bo);
+ if (found == NULL) {
+ res = add_bd_holder(bdev, bo);
+ if (res)
+ bd_release(bdev);
+ }
+ }
+
+ if (res || found)
+ free_bd_holder(bo);
+ mutex_unlock(&bdev->bd_mutex);
+
+ return res;
+}
+
+/**
+ * bd_release_from_kobject - bd_release() with additional kobject signature
+ *
+ * @bdev: block device to be released
+ * @kobj: holder's kobject
+ *
+ * Do bd_release() and remove sysfs symlinks created by bd_claim_by_kobject().
+ */
+static void bd_release_from_kobject(struct block_device *bdev,
+ struct kobject *kobj)
+{
+ struct bd_holder *bo;
+
+ if (!kobj)
+ return;
+
+ mutex_lock(&bdev->bd_mutex);
+ bd_release(bdev);
+ if ((bo = del_bd_holder(bdev, kobj)))
+ free_bd_holder(bo);
+ mutex_unlock(&bdev->bd_mutex);
+}
+
+/**
+ * bd_claim_by_disk - wrapper function for bd_claim_by_kobject()
+ *
+ * @bdev: block device to be claimed
+ * @holder: holder's signature
+ * @disk: holder's gendisk
+ *
+ * Call bd_claim_by_kobject() with getting @disk->slave_dir.
+ */
+int bd_claim_by_disk(struct block_device *bdev, void *holder,
+ struct gendisk *disk)
+{
+ return bd_claim_by_kobject(bdev, holder, kobject_get(disk->slave_dir));
+}
+EXPORT_SYMBOL_GPL(bd_claim_by_disk);
+
+/**
+ * bd_release_from_disk - wrapper function for bd_release_from_kobject()
+ *
+ * @bdev: block device to be claimed
+ * @disk: holder's gendisk
+ *
+ * Call bd_release_from_kobject() and put @disk->slave_dir.
+ */
+void bd_release_from_disk(struct block_device *bdev, struct gendisk *disk)
+{
+ bd_release_from_kobject(bdev, disk->slave_dir);
+ kobject_put(disk->slave_dir);
+}
+EXPORT_SYMBOL_GPL(bd_release_from_disk);
+#endif
+
/*
* Tries to open block device by device number. Use it ONLY if you
* really do not have anything better - i.e. when you are behind a
}
EXPORT_SYMBOL(bd_set_size);
-static int do_open(struct block_device *bdev, struct file *file)
+static int __blkdev_get(struct block_device *bdev, mode_t mode, unsigned flags,
+ int for_part);
+static int __blkdev_put(struct block_device *bdev, int for_part);
+
+static int do_open(struct block_device *bdev, struct file *file, int for_part)
{
struct module *owner = NULL;
struct gendisk *disk;
}
owner = disk->fops->owner;
- down(&bdev->bd_sem);
+ mutex_lock_nested(&bdev->bd_mutex, for_part);
if (!bdev->bd_openers) {
bdev->bd_disk = disk;
bdev->bd_contains = bdev;
ret = -ENOMEM;
if (!whole)
goto out_first;
- ret = blkdev_get(whole, file->f_mode, file->f_flags);
+ BUG_ON(for_part);
+ ret = __blkdev_get(whole, file->f_mode, file->f_flags, 1);
if (ret)
goto out_first;
bdev->bd_contains = whole;
- down(&whole->bd_sem);
- whole->bd_part_count++;
p = disk->part[part - 1];
bdev->bd_inode->i_data.backing_dev_info =
whole->bd_inode->i_data.backing_dev_info;
if (!(disk->flags & GENHD_FL_UP) || !p || !p->nr_sects) {
- whole->bd_part_count--;
- up(&whole->bd_sem);
ret = -ENXIO;
goto out_first;
}
kobject_get(&p->kobj);
bdev->bd_part = p;
bd_set_size(bdev, (loff_t) p->nr_sects << 9);
- up(&whole->bd_sem);
}
} else {
put_disk(disk);
}
if (bdev->bd_invalidated)
rescan_partitions(bdev->bd_disk, bdev);
- } else {
- down(&bdev->bd_contains->bd_sem);
- bdev->bd_contains->bd_part_count++;
- up(&bdev->bd_contains->bd_sem);
}
}
bdev->bd_openers++;
- up(&bdev->bd_sem);
+ if (for_part)
+ bdev->bd_part_count++;
+ mutex_unlock(&bdev->bd_mutex);
unlock_kernel();
return 0;
bdev->bd_disk = NULL;
bdev->bd_inode->i_data.backing_dev_info = &default_backing_dev_info;
if (bdev != bdev->bd_contains)
- blkdev_put(bdev->bd_contains);
+ __blkdev_put(bdev->bd_contains, 1);
bdev->bd_contains = NULL;
put_disk(disk);
module_put(owner);
out:
- up(&bdev->bd_sem);
+ mutex_unlock(&bdev->bd_mutex);
unlock_kernel();
if (ret)
bdput(bdev);
return ret;
}
-int blkdev_get(struct block_device *bdev, mode_t mode, unsigned flags)
+static int __blkdev_get(struct block_device *bdev, mode_t mode, unsigned flags,
+ int for_part)
{
/*
* This crockload is due to bad choice of ->open() type.
struct dentry fake_dentry = {};
fake_file.f_mode = mode;
fake_file.f_flags = flags;
- fake_file.f_dentry = &fake_dentry;
+ fake_file.f_path.dentry = &fake_dentry;
fake_dentry.d_inode = bdev->bd_inode;
- return do_open(bdev, &fake_file);
+ return do_open(bdev, &fake_file, for_part);
}
+int blkdev_get(struct block_device *bdev, mode_t mode, unsigned flags)
+{
+ return __blkdev_get(bdev, mode, flags, 0);
+}
EXPORT_SYMBOL(blkdev_get);
static int blkdev_open(struct inode * inode, struct file * filp)
filp->f_flags |= O_LARGEFILE;
bdev = bd_acquire(inode);
+ if (bdev == NULL)
+ return -ENOMEM;
- res = do_open(bdev, filp);
+ res = do_open(bdev, filp, 0);
if (res)
return res;
return res;
}
-int blkdev_put(struct block_device *bdev)
+static int __blkdev_put(struct block_device *bdev, int for_part)
{
int ret = 0;
struct inode *bd_inode = bdev->bd_inode;
struct gendisk *disk = bdev->bd_disk;
+ struct block_device *victim = NULL;
- down(&bdev->bd_sem);
+ mutex_lock_nested(&bdev->bd_mutex, for_part);
lock_kernel();
+ if (for_part)
+ bdev->bd_part_count--;
+
if (!--bdev->bd_openers) {
sync_blockdev(bdev);
kill_bdev(bdev);
if (bdev->bd_contains == bdev) {
if (disk->fops->release)
ret = disk->fops->release(bd_inode, NULL);
- } else {
- down(&bdev->bd_contains->bd_sem);
- bdev->bd_contains->bd_part_count--;
- up(&bdev->bd_contains->bd_sem);
}
if (!bdev->bd_openers) {
struct module *owner = disk->fops->owner;
}
bdev->bd_disk = NULL;
bdev->bd_inode->i_data.backing_dev_info = &default_backing_dev_info;
- if (bdev != bdev->bd_contains) {
- blkdev_put(bdev->bd_contains);
- }
+ if (bdev != bdev->bd_contains)
+ victim = bdev->bd_contains;
bdev->bd_contains = NULL;
}
unlock_kernel();
- up(&bdev->bd_sem);
+ mutex_unlock(&bdev->bd_mutex);
bdput(bdev);
+ if (victim)
+ __blkdev_put(victim, 1);
return ret;
}
+int blkdev_put(struct block_device *bdev)
+{
+ return __blkdev_put(bdev, 0);
+}
EXPORT_SYMBOL(blkdev_put);
static int blkdev_close(struct inode * inode, struct file * filp)
return blkdev_put(bdev);
}
-static ssize_t blkdev_file_write(struct file *file, const char __user *buf,
- size_t count, loff_t *ppos)
-{
- struct iovec local_iov = { .iov_base = (void __user *)buf, .iov_len = count };
-
- return generic_file_write_nolock(file, &local_iov, 1, ppos);
-}
-
-static ssize_t blkdev_file_aio_write(struct kiocb *iocb, const char __user *buf,
- size_t count, loff_t pos)
-{
- struct iovec local_iov = { .iov_base = (void __user *)buf, .iov_len = count };
-
- return generic_file_aio_write_nolock(iocb, &local_iov, 1, &iocb->ki_pos);
-}
-
static long block_ioctl(struct file *file, unsigned cmd, unsigned long arg)
{
return blkdev_ioctl(file->f_mapping->host, file, cmd, arg);
}
-struct address_space_operations def_blk_aops = {
+const struct address_space_operations def_blk_aops = {
.readpage = blkdev_readpage,
.writepage = blkdev_writepage,
.sync_page = block_sync_page,
.direct_IO = blkdev_direct_IO,
};
-struct file_operations def_blk_fops = {
+const struct file_operations def_blk_fops = {
.open = blkdev_open,
.release = blkdev_close,
.llseek = block_llseek,
- .read = generic_file_read,
- .write = blkdev_file_write,
+ .read = do_sync_read,
+ .write = do_sync_write,
.aio_read = generic_file_aio_read,
- .aio_write = blkdev_file_aio_write,
+ .aio_write = generic_file_aio_write_nolock,
.mmap = generic_file_mmap,
.fsync = block_fsync,
.unlocked_ioctl = block_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = compat_blkdev_ioctl,
#endif
- .readv = generic_file_readv,
- .writev = generic_file_write_nolock,
.sendfile = generic_file_sendfile,
+ .splice_read = generic_file_splice_read,
+ .splice_write = generic_file_splice_write,
};
int ioctl_by_bdev(struct block_device *bdev, unsigned cmd, unsigned long arg)
}
EXPORT_SYMBOL(close_bdev_excl);
+
+int __invalidate_device(struct block_device *bdev)
+{
+ 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);
+ drop_super(sb);
+ }
+ invalidate_bdev(bdev, 0);
+ return res;
+}
+EXPORT_SYMBOL(__invalidate_device);
git://git.onelab.eu / linux-2.6.git / blobdiff