* 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/device_cgroup.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 <linux/log2.h>
#include <asm/uaccess.h>
+#include "internal.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);
return retval;
}
-/* Kill _all_ buffers, dirty or not.. */
+/* Kill _all_ buffers and pagecache , dirty or not.. */
static void kill_bdev(struct block_device *bdev)
{
- invalidate_bdev(bdev, 1);
+ if (bdev->bd_inode->i_mapping->nrpages == 0)
+ return;
+ invalidate_bh_lrus();
truncate_inode_pages(bdev->bd_inode->i_mapping, 0);
}
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 || (size & (size-1)))
+ if (size > PAGE_SIZE || size < 512 || !is_power_of_2(size))
return -EINVAL;
/* Size cannot be smaller than the size supported by the device */
return block_read_full_page(page, blkdev_get_block);
}
-static int blkdev_prepare_write(struct file *file, struct page *page, unsigned from, unsigned to)
+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_prepare_write(page, from, to, blkdev_get_block);
+ *pagep = NULL;
+ return block_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
+ blkdev_get_block);
}
-static int blkdev_commit_write(struct file *file, struct page *page, unsigned from, unsigned to)
+static int blkdev_write_end(struct file *file, struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned copied,
+ struct page *page, void *fsdata)
{
- return block_commit_write(page, from, to);
+ int ret;
+ ret = block_write_end(file, mapping, pos, len, copied, page, fsdata);
+
+ unlock_page(page);
+ page_cache_release(page);
+
+ return ret;
}
/*
* 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 __read_mostly;
+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 bdev_inode *ei = (struct bdev_inode *) foo;
struct block_device *bdev = &ei->bdev;
- if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
- SLAB_CTOR_CONSTRUCTOR)
- {
- memset(bdev, 0, sizeof(*bdev));
- mutex_init(&bdev->bd_mutex);
- mutex_init(&bdev->bd_mount_mutex);
- INIT_LIST_HEAD(&bdev->bd_inodes);
- INIT_LIST_HEAD(&bdev->bd_list);
+ memset(bdev, 0, sizeof(*bdev));
+ 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);
+ INIT_LIST_HEAD(&bdev->bd_holder_list);
#endif
- inode_init_once(&ei->vfs_inode);
- }
+ inode_init_once(&ei->vfs_inode);
}
static inline void __bd_forget(struct inode *inode)
spin_unlock(&bdev_lock);
}
-static struct super_operations bdev_sops = {
+static const struct super_operations bdev_sops = {
.statfs = simple_statfs,
.alloc_inode = bdev_alloc_inode,
.destroy_inode = bdev_destroy_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 = {
bdev_cachep = kmem_cache_create("bdev_cache", sizeof(struct bdev_inode),
0, (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|
SLAB_MEM_SPREAD|SLAB_PANIC),
- init_once, NULL);
+ init_once);
err = register_filesystem(&bd_type);
if (err)
panic("Cannot register bdev pseudo-fs");
bd_mnt = kern_mount(&bd_type);
- err = PTR_ERR(bd_mnt);
if (IS_ERR(bd_mnt))
panic("Cannot create bdev pseudo-fs");
blockdev_superblock = bd_mnt->mnt_sb; /* For writeback */
long nr_blockdev_pages(void)
{
- struct list_head *p;
+ struct block_device *bdev;
long ret = 0;
spin_lock(&bdev_lock);
- list_for_each(p, &all_bdevs) {
- struct block_device *bdev;
- bdev = list_entry(p, struct block_device, bd_list);
+ list_for_each_entry(bdev, &all_bdevs, bd_list) {
ret += bdev->bd_inode->i_mapping->nrpages;
}
spin_unlock(&bdev_lock);
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)
static struct kobject *bdev_get_kobj(struct block_device *bdev)
{
if (bdev->bd_contains != bdev)
- return kobject_get(&bdev->bd_part->kobj);
+ return kobject_get(&bdev->bd_part->dev.kobj);
else
- return kobject_get(&bdev->bd_disk->kobj);
+ return kobject_get(&bdev->bd_disk->dev.kobj);
}
static struct kobject *bdev_get_holder(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)
}
/**
+ * 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()
*
- * If there is no matching entry with @bo in @bdev->bd_holder_list,
- * add @bo to the list, create symlinks.
+ * Add @bo to @bdev->bd_holder_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.
+ * Returns -ve if something fails.
*/
static int add_bd_holder(struct block_device *bdev, struct bd_holder *bo)
{
- struct bd_holder *tmp;
+ int err;
if (!bo)
- return 0;
-
- list_for_each_entry(tmp, &bdev->bd_holder_list, list) {
- if (tmp->sdir == bo->sdir) {
- tmp->count++;
- return 0;
- }
- }
+ return -EINVAL;
if (!bd_holder_grab_dirs(bdev, bo))
- return 0;
+ return -EBUSY;
+
+ err = add_symlink(bo->sdir, bo->sdev);
+ if (err)
+ return err;
+
+ err = add_symlink(bo->hdir, bo->hdev);
+ if (err) {
+ del_symlink(bo->sdir, bo->sdev);
+ return err;
+ }
- add_symlink(bo->sdir, bo->sdev);
- add_symlink(bo->hdir, bo->hdev);
list_add_tail(&bo->list, &bdev->bd_holder_list);
- return 1;
+ return 0;
}
/**
static int bd_claim_by_kobject(struct block_device *bdev, void *holder,
struct kobject *kobj)
{
- int res;
- struct bd_holder *bo;
+ int err;
+ struct bd_holder *bo, *found;
if (!kobj)
return -EINVAL;
return -ENOMEM;
mutex_lock(&bdev->bd_mutex);
- res = bd_claim(bdev, holder);
- if (res || !add_bd_holder(bdev, bo))
- free_bd_holder(bo);
- mutex_unlock(&bdev->bd_mutex);
- return res;
+ err = bd_claim(bdev, holder);
+ if (err)
+ goto fail;
+
+ found = find_bd_holder(bdev, bo);
+ if (found)
+ goto fail;
+
+ err = add_bd_holder(bdev, bo);
+ if (err)
+ bd_release(bdev);
+ else
+ bo = NULL;
+fail:
+ mutex_unlock(&bdev->bd_mutex);
+ free_bd_holder(bo);
+ return err;
}
/**
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);
+ free_bd_holder(del_bd_holder(bdev, kobj));
mutex_unlock(&bdev->bd_mutex);
}
if (bdops->revalidate_disk)
bdops->revalidate_disk(bdev->bd_disk);
- if (bdev->bd_disk->minors > 1)
+ if (disk_max_parts(bdev->bd_disk))
bdev->bd_invalidated = 1;
return 1;
}
}
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);
+
+/*
+ * bd_mutex locking:
+ *
+ * mutex_lock(part->bd_mutex)
+ * mutex_lock_nested(whole->bd_mutex, 1)
+ */
+
+static int do_open(struct block_device *bdev, struct file *file, int for_part)
{
struct module *owner = NULL;
struct gendisk *disk;
- int ret = -ENXIO;
- int part;
+ struct hd_struct *part = NULL;
+ int ret;
+ int partno;
+ int perm = 0;
+
+ if (file->f_mode & FMODE_READ)
+ perm |= MAY_READ;
+ if (file->f_mode & FMODE_WRITE)
+ perm |= MAY_WRITE;
+ /*
+ * hooks: /n/, see "layering violations".
+ */
+ ret = devcgroup_inode_permission(bdev->bd_inode, perm);
+ if (ret != 0) {
+ bdput(bdev);
+ return ret;
+ }
+ ret = -ENXIO;
file->f_mapping = bdev->bd_inode->i_mapping;
lock_kernel();
- disk = get_gendisk(bdev->bd_dev, &part);
+ disk = get_gendisk(bdev->bd_dev, &partno);
if (!disk) {
unlock_kernel();
bdput(bdev);
}
owner = disk->fops->owner;
- mutex_lock(&bdev->bd_mutex);
+ mutex_lock_nested(&bdev->bd_mutex, for_part);
if (!bdev->bd_openers) {
bdev->bd_disk = disk;
bdev->bd_contains = bdev;
- if (!part) {
+ if (!partno) {
struct backing_dev_info *bdi;
if (disk->fops->open) {
ret = disk->fops->open(bdev->bd_inode, file);
if (bdev->bd_invalidated)
rescan_partitions(disk, bdev);
} else {
- struct hd_struct *p;
struct block_device *whole;
whole = bdget_disk(disk, 0);
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;
- mutex_lock(&whole->bd_mutex);
- whole->bd_part_count++;
- p = disk->part[part - 1];
+ part = disk_get_part(disk, partno);
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--;
- mutex_unlock(&whole->bd_mutex);
+ if (!(disk->flags & GENHD_FL_UP) ||
+ !part || !part->nr_sects) {
ret = -ENXIO;
goto out_first;
}
- kobject_get(&p->kobj);
- bdev->bd_part = p;
- bd_set_size(bdev, (loff_t) p->nr_sects << 9);
- mutex_unlock(&whole->bd_mutex);
+ bdev->bd_part = part;
+ bd_set_size(bdev, (loff_t)part->nr_sects << 9);
}
} else {
put_disk(disk);
}
if (bdev->bd_invalidated)
rescan_partitions(bdev->bd_disk, bdev);
- } else {
- mutex_lock(&bdev->bd_contains->bd_mutex);
- bdev->bd_contains->bd_part_count++;
- mutex_unlock(&bdev->bd_contains->bd_mutex);
}
}
bdev->bd_openers++;
+ 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);
+ disk_put_part(part);
module_put(owner);
out:
mutex_unlock(&bdev->bd_mutex);
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;
- mutex_lock(&bdev->bd_mutex);
+ 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 {
- 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;
module_put(owner);
if (bdev->bd_contains != bdev) {
- kobject_put(&bdev->bd_part->kobj);
+ disk_put_part(bdev->bd_part);
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);
- }
+ if (bdev != bdev->bd_contains)
+ victim = bdev->bd_contains;
bdev->bd_contains = NULL;
}
unlock_kernel();
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 = {
+static const struct address_space_operations def_blk_aops = {
.readpage = blkdev_readpage,
.writepage = blkdev_writepage,
.sync_page = block_sync_page,
- .prepare_write = blkdev_prepare_write,
- .commit_write = blkdev_commit_write,
+ .write_begin = blkdev_write_begin,
+ .write_end = blkdev_write_end,
.writepages = generic_writepages,
.direct_IO = blkdev_direct_IO,
};
.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,
};
if (error)
return ERR_PTR(error);
- inode = nd.dentry->d_inode;
+ inode = nd.path.dentry->d_inode;
error = -ENOTBLK;
if (!S_ISBLK(inode->i_mode))
goto fail;
error = -EACCES;
- if (nd.mnt->mnt_flags & MNT_NODEV)
+ if (nd.path.mnt->mnt_flags & MNT_NODEV)
goto fail;
error = -ENOMEM;
bdev = bd_acquire(inode);
if (!bdev)
goto fail;
out:
- path_release(&nd);
+ path_put(&nd.path);
return bdev;
fail:
bdev = ERR_PTR(error);
goto out;
}
+EXPORT_SYMBOL(lookup_bdev);
/**
* open_bdev_excl - open a block device by name and set it up for use
}
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);
+ return res;
+}
+EXPORT_SYMBOL(__invalidate_device);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff