#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;
return kobject_get(bdev->bd_disk->holder_dir);
}
-static void add_symlink(struct kobject *from, struct kobject *to)
+static int add_symlink(struct kobject *from, struct kobject *to)
{
if (!from || !to)
- return;
- sysfs_create_link(from, to, kobject_name(to));
+ return 0;
+ return sysfs_create_link(from, to, kobject_name(to));
}
static void del_symlink(struct kobject *from, struct kobject *to)
* If there is no matching entry with @bo in @bdev->bd_holder_list,
* add @bo to the list, create symlinks.
*
- * Returns 1 if @bo was added to the list.
- * Returns 0 if @bo wasn't used by any reason and should be freed.
+ * Returns 0 if symlinks are created or already there.
+ * Returns -ve if something fails and @bo can be freed.
*/
static int add_bd_holder(struct block_device *bdev, struct bd_holder *bo)
{
struct bd_holder *tmp;
+ int ret;
if (!bo)
- return 0;
+ return -EINVAL;
list_for_each_entry(tmp, &bdev->bd_holder_list, list) {
if (tmp->sdir == bo->sdir) {
tmp->count++;
+ /* We've already done what we need to do here. */
+ free_bd_holder(bo);
return 0;
}
}
if (!bd_holder_grab_dirs(bdev, bo))
- return 0;
+ return -EBUSY;
- add_symlink(bo->sdir, bo->sdev);
- add_symlink(bo->hdir, bo->hdev);
- list_add_tail(&bo->list, &bdev->bd_holder_list);
- return 1;
+ 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;
}
/**
if (!bo)
return -ENOMEM;
- mutex_lock(&bdev->bd_mutex);
+ mutex_lock_nested(&bdev->bd_mutex, BD_MUTEX_PARTITION);
res = bd_claim(bdev, holder);
- if (res || !add_bd_holder(bdev, bo))
+ if (res == 0)
+ res = add_bd_holder(bdev, bo);
+ if (res)
free_bd_holder(bo);
mutex_unlock(&bdev->bd_mutex);
if (!kobj)
return;
- mutex_lock(&bdev->bd_mutex);
+ mutex_lock_nested(&bdev->bd_mutex, BD_MUTEX_PARTITION);
bd_release(bdev);
if ((bo = del_bd_holder(bdev, kobj)))
free_bd_holder(bo);
EXPORT_SYMBOL(open_by_devnum);
+static int
+blkdev_get_partition(struct block_device *bdev, mode_t mode, unsigned flags);
+
+struct block_device *open_partition_by_devnum(dev_t dev, unsigned mode)
+{
+ struct block_device *bdev = bdget(dev);
+ int err = -ENOMEM;
+ int flags = mode & FMODE_WRITE ? O_RDWR : O_RDONLY;
+ if (bdev)
+ err = blkdev_get_partition(bdev, mode, flags);
+ return err ? ERR_PTR(err) : bdev;
+}
+
+EXPORT_SYMBOL(open_partition_by_devnum);
+
+
/*
* This routine checks whether a removable media has been changed,
* and invalidates all buffer-cache-entries in that case. This
}
EXPORT_SYMBOL(bd_set_size);
-static int do_open(struct block_device *bdev, struct file *file)
+static int __blkdev_put(struct block_device *bdev, unsigned int subclass)
+{
+ int ret = 0;
+ struct inode *bd_inode = bdev->bd_inode;
+ struct gendisk *disk = bdev->bd_disk;
+
+ mutex_lock_nested(&bdev->bd_mutex, subclass);
+ lock_kernel();
+ 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 {
+ mutex_lock_nested(&bdev->bd_contains->bd_mutex,
+ subclass + 1);
+ bdev->bd_contains->bd_part_count--;
+ mutex_unlock(&bdev->bd_contains->bd_mutex);
+ }
+ if (!bdev->bd_openers) {
+ struct module *owner = disk->fops->owner;
+
+ put_disk(disk);
+ module_put(owner);
+
+ if (bdev->bd_contains != bdev) {
+ kobject_put(&bdev->bd_part->kobj);
+ bdev->bd_part = NULL;
+ }
+ 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, subclass + 1);
+ bdev->bd_contains = NULL;
+ }
+ unlock_kernel();
+ mutex_unlock(&bdev->bd_mutex);
+ bdput(bdev);
+ return ret;
+}
+
+int blkdev_put(struct block_device *bdev)
+{
+ return __blkdev_put(bdev, BD_MUTEX_NORMAL);
+}
+EXPORT_SYMBOL(blkdev_put);
+
+int blkdev_put_partition(struct block_device *bdev)
+{
+ return __blkdev_put(bdev, BD_MUTEX_PARTITION);
+}
+EXPORT_SYMBOL(blkdev_put_partition);
+
+static int
+blkdev_get_whole(struct block_device *bdev, mode_t mode, unsigned flags);
+
+static int
+do_open(struct block_device *bdev, struct file *file, unsigned int subclass)
{
struct module *owner = NULL;
struct gendisk *disk;
}
owner = disk->fops->owner;
- mutex_lock(&bdev->bd_mutex);
+ mutex_lock_nested(&bdev->bd_mutex, subclass);
+
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);
+ ret = blkdev_get_whole(whole, file->f_mode, file->f_flags);
if (ret)
goto out_first;
bdev->bd_contains = whole;
- mutex_lock(&whole->bd_mutex);
+ mutex_lock_nested(&whole->bd_mutex, BD_MUTEX_WHOLE);
whole->bd_part_count++;
p = disk->part[part - 1];
bdev->bd_inode->i_data.backing_dev_info =
if (bdev->bd_invalidated)
rescan_partitions(bdev->bd_disk, bdev);
} else {
- mutex_lock(&bdev->bd_contains->bd_mutex);
+ mutex_lock_nested(&bdev->bd_contains->bd_mutex,
+ BD_MUTEX_WHOLE);
bdev->bd_contains->bd_part_count++;
mutex_unlock(&bdev->bd_contains->bd_mutex);
}
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, BD_MUTEX_WHOLE);
bdev->bd_contains = NULL;
put_disk(disk);
module_put(owner);
fake_file.f_dentry = &fake_dentry;
fake_dentry.d_inode = bdev->bd_inode;
- return do_open(bdev, &fake_file);
+ return do_open(bdev, &fake_file, BD_MUTEX_NORMAL);
}
EXPORT_SYMBOL(blkdev_get);
+static int
+blkdev_get_whole(struct block_device *bdev, mode_t mode, unsigned flags)
+{
+ /*
+ * This crockload is due to bad choice of ->open() type.
+ * It will go away.
+ * For now, block device ->open() routine must _not_
+ * examine anything in 'inode' argument except ->i_rdev.
+ */
+ struct file fake_file = {};
+ struct dentry fake_dentry = {};
+ fake_file.f_mode = mode;
+ fake_file.f_flags = flags;
+ fake_file.f_dentry = &fake_dentry;
+ fake_dentry.d_inode = bdev->bd_inode;
+
+ return do_open(bdev, &fake_file, BD_MUTEX_WHOLE);
+}
+
+static int
+blkdev_get_partition(struct block_device *bdev, mode_t mode, unsigned flags)
+{
+ /*
+ * This crockload is due to bad choice of ->open() type.
+ * It will go away.
+ * For now, block device ->open() routine must _not_
+ * examine anything in 'inode' argument except ->i_rdev.
+ */
+ struct file fake_file = {};
+ struct dentry fake_dentry = {};
+ fake_file.f_mode = mode;
+ fake_file.f_flags = flags;
+ fake_file.f_dentry = &fake_dentry;
+ fake_dentry.d_inode = bdev->bd_inode;
+
+ return do_open(bdev, &fake_file, BD_MUTEX_PARTITION);
+}
+
static int blkdev_open(struct inode * inode, struct file * filp)
{
struct block_device *bdev;
bdev = bd_acquire(inode);
- res = do_open(bdev, filp);
+ res = do_open(bdev, filp, BD_MUTEX_NORMAL);
if (res)
return res;
return res;
}
-int blkdev_put(struct block_device *bdev)
-{
- int ret = 0;
- struct inode *bd_inode = bdev->bd_inode;
- struct gendisk *disk = bdev->bd_disk;
-
- mutex_lock(&bdev->bd_mutex);
- lock_kernel();
- 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 {
- mutex_lock(&bdev->bd_contains->bd_mutex);
- bdev->bd_contains->bd_part_count--;
- mutex_unlock(&bdev->bd_contains->bd_mutex);
- }
- if (!bdev->bd_openers) {
- struct module *owner = disk->fops->owner;
-
- put_disk(disk);
- module_put(owner);
-
- if (bdev->bd_contains != bdev) {
- kobject_put(&bdev->bd_part->kobj);
- bdev->bd_part = NULL;
- }
- 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);
- }
- bdev->bd_contains = NULL;
- }
- unlock_kernel();
- mutex_unlock(&bdev->bd_mutex);
- bdput(bdev);
- return ret;
-}
-
-EXPORT_SYMBOL(blkdev_put);
-
static int blkdev_close(struct inode * inode, struct file * filp)
{
struct block_device *bdev = I_BDEV(filp->f_mapping->host);
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);
.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,
}
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);