X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=fs%2Fblock_dev.c;h=b3c1efff5e1db0180c610bf0df465527587c934c;hb=7ef0d7377cb287e08f3ae94cebc919448e1f5dff;hp=d9bdf2b3ade2922a0564a4630f3b3ce461d1c176;hpb=cda9205da24aeaa8fb086b0fb85cdf39571ecc3f;p=safe%2Fjmp%2Flinux-2.6 diff --git a/fs/block_dev.c b/fs/block_dev.c index d9bdf2b..b3c1eff 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -12,6 +12,7 @@ #include #include #include +#include #include #include #include @@ -22,6 +23,7 @@ #include #include #include +#include #include #include "internal.h" @@ -30,6 +32,8 @@ struct bdev_inode { 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); @@ -55,17 +59,19 @@ static sector_t max_block(struct block_device *bdev) 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 */ @@ -129,199 +135,43 @@ blkdev_get_block(struct inode *inode, sector_t iblock, return 0; } -static int blk_end_aio(struct bio *bio, unsigned int bytes_done, int error) +static int +blkdev_get_blocks(struct inode *inode, sector_t iblock, + struct buffer_head *bh, int create) { - 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); - } + sector_t end_block = max_block(I_BDEV(inode)); + unsigned long max_blocks = bh->b_size >> inode->i_blkbits; - /* 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); + if ((iblock + max_blocks) > end_block) { + max_blocks = end_block - iblock; + if ((long)max_blocks <= 0) { + if (create) + return -EIO; /* write fully beyond EOF */ + /* + * It is a read which is fully beyond EOF. We return + * a !buffer_mapped buffer + */ + max_blocks = 0; + } } + bh->b_bdev = I_BDEV(inode); + bh->b_blocknr = iblock; + bh->b_size = max_blocks << inode->i_blkbits; + if (max_blocks) + set_buffer_mapped(bh); 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); + loff_t offset, unsigned long nr_segs) +{ + struct file *file = iocb->ki_filp; + struct inode *inode = file->f_mapping->host; - /* - * 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; + return blockdev_direct_IO_no_locking(rw, iocb, inode, I_BDEV(inode), + iov, offset, nr_segs, blkdev_get_blocks, NULL); } static int blkdev_writepage(struct page *page, struct writeback_control *wbc) @@ -334,14 +184,26 @@ static int blkdev_readpage(struct file * file, struct page * page) 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; } /* @@ -409,24 +271,22 @@ static void bdev_destroy_inode(struct inode *inode) kmem_cache_free(bdev_cachep, bdi); } -static void init_once(void * foo, struct kmem_cache * 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); - sema_init(&bdev->bd_mount_sem, 1); - 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); + /* Initialize mutex for freeze. */ + mutex_init(&bdev->bd_fsfreeze_mutex); } static inline void __bd_forget(struct inode *inode) @@ -448,7 +308,7 @@ static void bdev_clear_inode(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, @@ -468,21 +328,21 @@ static struct file_system_type bd_type = { .kill_sb = kill_anon_super, }; -static struct vfsmount *bd_mnt __read_mostly; -struct super_block *blockdev_superblock; +struct super_block *blockdev_superblock __read_mostly; void __init bdev_cache_init(void) { int err; + 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_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 */ @@ -516,7 +376,7 @@ struct block_device *bdget(dev_t dev) struct block_device *bdev; struct inode *inode; - inode = iget5_locked(bd_mnt->mnt_sb, hash(dev), + inode = iget5_locked(blockdev_superblock, hash(dev), bdev_test, bdev_set, &dev); if (!inode) @@ -548,12 +408,10 @@ EXPORT_SYMBOL(bdget); 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); @@ -608,7 +466,7 @@ void bd_forget(struct inode *inode) spin_lock(&bdev_lock); if (inode->i_bdev) { - if (inode->i_sb != blockdev_superblock) + if (!sb_is_blkdev_sb(inode->i_sb)) bdev = inode->i_bdev; __bd_forget(inode); } @@ -685,22 +543,6 @@ EXPORT_SYMBOL(bd_release); * /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) @@ -749,11 +591,11 @@ static int bd_holder_grab_dirs(struct block_device *bdev, if (!bo->hdev) goto fail_put_sdir; - bo->sdev = bdev_get_kobj(bdev); + bo->sdev = kobject_get(&part_to_dev(bdev->bd_part)->kobj); if (!bo->sdev) goto fail_put_hdev; - bo->hdir = bdev_get_holder(bdev); + bo->hdir = kobject_get(bdev->bd_part->holder_dir); if (!bo->hdir) goto fail_put_sdev; @@ -834,7 +676,7 @@ static struct bd_holder *find_bd_holder(struct block_device *bdev, */ static int add_bd_holder(struct block_device *bdev, struct bd_holder *bo) { - int ret; + int err; if (!bo) return -EINVAL; @@ -842,15 +684,18 @@ static int add_bd_holder(struct block_device *bdev, struct bd_holder *bo) 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); + 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; } - if (ret == 0) - list_add_tail(&bo->list, &bdev->bd_holder_list); - return ret; + + list_add_tail(&bo->list, &bdev->bd_holder_list); + return 0; } /** @@ -908,7 +753,7 @@ static struct bd_holder *del_bd_holder(struct block_device *bdev, static int bd_claim_by_kobject(struct block_device *bdev, void *holder, struct kobject *kobj) { - int res; + int err; struct bd_holder *bo, *found; if (!kobj) @@ -919,21 +764,24 @@ static int bd_claim_by_kobject(struct block_device *bdev, void *holder, 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); + err = bd_claim(bdev, holder); + if (err) + goto fail; - return res; + 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; } /** @@ -947,15 +795,12 @@ static int bd_claim_by_kobject(struct block_device *bdev, void *holder, 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); } @@ -998,18 +843,98 @@ EXPORT_SYMBOL_GPL(bd_release_from_disk); * to be used for internal purposes. If you ever need it - reconsider * your API. */ -struct block_device *open_by_devnum(dev_t dev, unsigned mode) +struct block_device *open_by_devnum(dev_t dev, fmode_t mode) { struct block_device *bdev = bdget(dev); int err = -ENOMEM; - int flags = mode & FMODE_WRITE ? O_RDWR : O_RDONLY; if (bdev) - err = blkdev_get(bdev, mode, flags); + err = blkdev_get(bdev, mode); return err ? ERR_PTR(err) : bdev; } EXPORT_SYMBOL(open_by_devnum); +/** + * flush_disk - invalidates all buffer-cache entries on a disk + * + * @bdev: struct block device to be flushed + * + * Invalidates all buffer-cache entries on a disk. It should be called + * when a disk has been changed -- either by a media change or online + * resize. + */ +static void flush_disk(struct block_device *bdev) +{ + if (__invalidate_device(bdev)) { + char name[BDEVNAME_SIZE] = ""; + + if (bdev->bd_disk) + disk_name(bdev->bd_disk, 0, name); + printk(KERN_WARNING "VFS: busy inodes on changed media or " + "resized disk %s\n", name); + } + + if (!bdev->bd_disk) + return; + if (disk_partitionable(bdev->bd_disk)) + bdev->bd_invalidated = 1; +} + +/** + * check_disk_size_change - checks for disk size change and adjusts bdev size. + * @disk: struct gendisk to check + * @bdev: struct bdev to adjust. + * + * This routine checks to see if the bdev size does not match the disk size + * and adjusts it if it differs. + */ +void check_disk_size_change(struct gendisk *disk, struct block_device *bdev) +{ + loff_t disk_size, bdev_size; + + disk_size = (loff_t)get_capacity(disk) << 9; + bdev_size = i_size_read(bdev->bd_inode); + if (disk_size != bdev_size) { + char name[BDEVNAME_SIZE]; + + disk_name(disk, 0, name); + printk(KERN_INFO + "%s: detected capacity change from %lld to %lld\n", + name, bdev_size, disk_size); + i_size_write(bdev->bd_inode, disk_size); + flush_disk(bdev); + } +} +EXPORT_SYMBOL(check_disk_size_change); + +/** + * revalidate_disk - wrapper for lower-level driver's revalidate_disk call-back + * @disk: struct gendisk to be revalidated + * + * This routine is a wrapper for lower-level driver's revalidate_disk + * call-backs. It is used to do common pre and post operations needed + * for all revalidate_disk operations. + */ +int revalidate_disk(struct gendisk *disk) +{ + struct block_device *bdev; + int ret = 0; + + if (disk->fops->revalidate_disk) + ret = disk->fops->revalidate_disk(disk); + + bdev = bdget_disk(disk, 0); + if (!bdev) + return ret; + + mutex_lock(&bdev->bd_mutex); + check_disk_size_change(disk, bdev); + mutex_unlock(&bdev->bd_mutex); + bdput(bdev); + return ret; +} +EXPORT_SYMBOL(revalidate_disk); + /* * This routine checks whether a removable media has been changed, * and invalidates all buffer-cache-entries in that case. This @@ -1029,13 +954,9 @@ int check_disk_change(struct block_device *bdev) if (!bdops->media_changed(bdev->bd_disk)) return 0; - if (__invalidate_device(bdev)) - printk("VFS: busy inodes on changed media.\n"); - + flush_disk(bdev); if (bdops->revalidate_disk) bdops->revalidate_disk(bdev->bd_disk); - if (bdev->bd_disk->minors > 1) - bdev->bd_invalidated = 1; return 1; } @@ -1056,37 +977,72 @@ void bd_set_size(struct block_device *bdev, loff_t size) } EXPORT_SYMBOL(bd_set_size); -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 __blkdev_put(struct block_device *bdev, fmode_t mode, int for_part); -static int do_open(struct block_device *bdev, struct file *file, int for_part) +/* + * bd_mutex locking: + * + * mutex_lock(part->bd_mutex) + * mutex_lock_nested(whole->bd_mutex, 1) + */ + +static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part) { - struct module *owner = NULL; struct gendisk *disk; - int ret = -ENXIO; - int part; + int ret; + int partno; + int perm = 0; - file->f_mapping = bdev->bd_inode->i_mapping; - lock_kernel(); - disk = get_gendisk(bdev->bd_dev, &part); - if (!disk) { - unlock_kernel(); + if (mode & FMODE_READ) + perm |= MAY_READ; + if (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; } - owner = disk->fops->owner; + + lock_kernel(); + restart: + + ret = -ENXIO; + disk = get_gendisk(bdev->bd_dev, &partno); + if (!disk) + goto out_unlock_kernel; 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; + + ret = -ENXIO; + bdev->bd_part = disk_get_part(disk, partno); + if (!bdev->bd_part) + goto out_clear; + if (disk->fops->open) { - ret = disk->fops->open(bdev->bd_inode, file); + ret = disk->fops->open(bdev, mode); + if (ret == -ERESTARTSYS) { + /* Lost a race with 'disk' being + * deleted, try again. + * See md.c + */ + disk_put_part(bdev->bd_part); + bdev->bd_part = NULL; + module_put(disk->fops->owner); + put_disk(disk); + bdev->bd_disk = NULL; + mutex_unlock(&bdev->bd_mutex); + goto restart; + } if (ret) - goto out_first; + goto out_clear; } if (!bdev->bd_openers) { bd_set_size(bdev,(loff_t)get_capacity(disk)<<9); @@ -1098,36 +1054,35 @@ static int do_open(struct block_device *bdev, struct file *file, int for_part) 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; + goto out_clear; BUG_ON(for_part); - ret = __blkdev_get(whole, file->f_mode, file->f_flags, 1); + ret = __blkdev_get(whole, mode, 1); if (ret) - goto out_first; + goto out_clear; bdev->bd_contains = whole; - 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) { + bdev->bd_part = disk_get_part(disk, partno); + if (!(disk->flags & GENHD_FL_UP) || + !bdev->bd_part || !bdev->bd_part->nr_sects) { ret = -ENXIO; - goto out_first; + goto out_clear; } - kobject_get(&p->kobj); - bdev->bd_part = p; - bd_set_size(bdev, (loff_t) p->nr_sects << 9); + bd_set_size(bdev, (loff_t)bdev->bd_part->nr_sects << 9); } } else { put_disk(disk); - module_put(owner); + module_put(disk->fops->owner); + disk = NULL; if (bdev->bd_contains == bdev) { if (bdev->bd_disk->fops->open) { - ret = bdev->bd_disk->fops->open(bdev->bd_inode, file); + ret = bdev->bd_disk->fops->open(bdev, mode); if (ret) - goto out; + goto out_unlock_bdev; } if (bdev->bd_invalidated) rescan_partitions(bdev->bd_disk, bdev); @@ -1140,44 +1095,30 @@ static int do_open(struct block_device *bdev, struct file *file, int for_part) unlock_kernel(); return 0; -out_first: + out_clear: + disk_put_part(bdev->bd_part); bdev->bd_disk = NULL; + bdev->bd_part = NULL; bdev->bd_inode->i_data.backing_dev_info = &default_backing_dev_info; if (bdev != bdev->bd_contains) - __blkdev_put(bdev->bd_contains, 1); + __blkdev_put(bdev->bd_contains, mode, 1); bdev->bd_contains = NULL; - put_disk(disk); - module_put(owner); -out: + out_unlock_bdev: mutex_unlock(&bdev->bd_mutex); + out_unlock_kernel: unlock_kernel(); - if (ret) - bdput(bdev); - return ret; -} -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. - * 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_path.dentry = &fake_dentry; - fake_dentry.d_inode = bdev->bd_inode; + if (disk) + module_put(disk->fops->owner); + put_disk(disk); + bdput(bdev); - return do_open(bdev, &fake_file, for_part); + return ret; } -int blkdev_get(struct block_device *bdev, mode_t mode, unsigned flags) +int blkdev_get(struct block_device *bdev, fmode_t mode) { - return __blkdev_get(bdev, mode, flags, 0); + return __blkdev_get(bdev, mode, 0); } EXPORT_SYMBOL(blkdev_get); @@ -1194,28 +1135,39 @@ static int blkdev_open(struct inode * inode, struct file * filp) */ filp->f_flags |= O_LARGEFILE; + 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 = bd_acquire(inode); if (bdev == NULL) return -ENOMEM; - res = do_open(bdev, filp, 0); + filp->f_mapping = bdev->bd_inode->i_mapping; + + res = blkdev_get(bdev, filp->f_mode); if (res) return res; - if (!(filp->f_flags & O_EXCL) ) - return 0; + if (filp->f_mode & FMODE_EXCL) { + res = bd_claim(bdev, filp); + if (res) + goto out_blkdev_put; + } - if (!(res = bd_claim(bdev, filp))) - return 0; + return 0; - blkdev_put(bdev); + out_blkdev_put: + blkdev_put(bdev, filp->f_mode); return res; } -static int __blkdev_put(struct block_device *bdev, int for_part) +static int __blkdev_put(struct block_device *bdev, fmode_t mode, int for_part) { int ret = 0; - struct inode *bd_inode = bdev->bd_inode; struct gendisk *disk = bdev->bd_disk; struct block_device *victim = NULL; @@ -1230,18 +1182,15 @@ static int __blkdev_put(struct block_device *bdev, int for_part) } if (bdev->bd_contains == bdev) { if (disk->fops->release) - ret = disk->fops->release(bd_inode, NULL); + ret = disk->fops->release(disk, mode); } 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; - } + 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) @@ -1252,13 +1201,13 @@ static int __blkdev_put(struct block_device *bdev, int for_part) mutex_unlock(&bdev->bd_mutex); bdput(bdev); if (victim) - __blkdev_put(victim, 1); + __blkdev_put(victim, mode, 1); return ret; } -int blkdev_put(struct block_device *bdev) +int blkdev_put(struct block_device *bdev, fmode_t mode) { - return __blkdev_put(bdev, 0); + return __blkdev_put(bdev, mode, 0); } EXPORT_SYMBOL(blkdev_put); @@ -1267,21 +1216,48 @@ static int blkdev_close(struct inode * inode, struct file * filp) struct block_device *bdev = I_BDEV(filp->f_mapping->host); if (bdev->bd_holder == filp) bd_release(bdev); - return blkdev_put(bdev); + return blkdev_put(bdev, filp->f_mode); } static long block_ioctl(struct file *file, unsigned cmd, unsigned long arg) { - return blkdev_ioctl(file->f_mapping->host, file, cmd, arg); + struct block_device *bdev = I_BDEV(file->f_mapping->host); + 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); +} + +/* + * Try to release a page associated with block device when the system + * is under memory pressure. + */ +static int blkdev_releasepage(struct page *page, gfp_t wait) +{ + struct super_block *super = BDEV_I(page->mapping->host)->bdev.bd_super; + + if (super && super->s_op->bdev_try_to_free_page) + return super->s_op->bdev_try_to_free_page(super, page, wait); + + return try_to_free_buffers(page); } -const 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, + .releasepage = blkdev_releasepage, .direct_IO = blkdev_direct_IO, }; @@ -1299,7 +1275,6 @@ const struct file_operations def_blk_fops = { #ifdef CONFIG_COMPAT .compat_ioctl = compat_blkdev_ioctl, #endif - .sendfile = generic_file_sendfile, .splice_read = generic_file_splice_read, .splice_write = generic_file_splice_write, }; @@ -1309,7 +1284,7 @@ int ioctl_by_bdev(struct block_device *bdev, unsigned cmd, unsigned long arg) int res; mm_segment_t old_fs = get_fs(); set_fs(KERNEL_DS); - res = blkdev_ioctl(bdev->bd_inode, NULL, cmd, arg); + res = blkdev_ioctl(bdev, 0, cmd, arg); set_fs(old_fs); return res; } @@ -1318,73 +1293,70 @@ EXPORT_SYMBOL(ioctl_by_bdev); /** * lookup_bdev - lookup a struct block_device by name + * @pathname: special file representing the block device * - * @path: special file representing the block device - * - * Get a reference to the blockdevice at @path in the current + * Get a reference to the blockdevice at @pathname in the current * namespace if possible and return it. Return ERR_PTR(error) * otherwise. */ -struct block_device *lookup_bdev(const char *path) +struct block_device *lookup_bdev(const char *pathname) { struct block_device *bdev; struct inode *inode; - struct nameidata nd; + struct path path; int error; - if (!path || !*path) + if (!pathname || !*pathname) return ERR_PTR(-EINVAL); - error = path_lookup(path, LOOKUP_FOLLOW, &nd); + error = kern_path(pathname, LOOKUP_FOLLOW, &path); if (error) return ERR_PTR(error); - inode = nd.dentry->d_inode; + inode = path.dentry->d_inode; error = -ENOTBLK; if (!S_ISBLK(inode->i_mode)) goto fail; error = -EACCES; - if (nd.mnt->mnt_flags & MNT_NODEV) + if (path.mnt->mnt_flags & MNT_NODEV) goto fail; error = -ENOMEM; bdev = bd_acquire(inode); if (!bdev) goto fail; out: - path_release(&nd); + path_put(&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 + * open_bdev_exclusive - open a block device by name and set it up for use * * @path: special file representing the block device - * @flags: %MS_RDONLY for opening read-only + * @mode: FMODE_... combination to pass be used * @holder: owner for exclusion * * Open the blockdevice described by the special file at @path, claim it * for the @holder. */ -struct block_device *open_bdev_excl(const char *path, int flags, void *holder) +struct block_device *open_bdev_exclusive(const char *path, fmode_t mode, void *holder) { struct block_device *bdev; - mode_t mode = FMODE_READ; int error = 0; bdev = lookup_bdev(path); if (IS_ERR(bdev)) return bdev; - if (!(flags & MS_RDONLY)) - mode |= FMODE_WRITE; - error = blkdev_get(bdev, mode, 0); + error = blkdev_get(bdev, mode); if (error) return ERR_PTR(error); error = -EACCES; - if (!(flags & MS_RDONLY) && bdev_read_only(bdev)) + if ((mode & FMODE_WRITE) && bdev_read_only(bdev)) goto blkdev_put; error = bd_claim(bdev, holder); if (error) @@ -1393,26 +1365,27 @@ struct block_device *open_bdev_excl(const char *path, int flags, void *holder) return bdev; blkdev_put: - blkdev_put(bdev); + blkdev_put(bdev, mode); return ERR_PTR(error); } -EXPORT_SYMBOL(open_bdev_excl); +EXPORT_SYMBOL(open_bdev_exclusive); /** - * close_bdev_excl - release a blockdevice openen by open_bdev_excl() + * close_bdev_exclusive - close a blockdevice opened by open_bdev_exclusive() * * @bdev: blockdevice to close + * @mode: mode, must match that used to open. * - * This is the counterpart to open_bdev_excl(). + * This is the counterpart to open_bdev_exclusive(). */ -void close_bdev_excl(struct block_device *bdev) +void close_bdev_exclusive(struct block_device *bdev, fmode_t mode) { bd_release(bdev); - blkdev_put(bdev); + blkdev_put(bdev, mode); } -EXPORT_SYMBOL(close_bdev_excl); +EXPORT_SYMBOL(close_bdev_exclusive); int __invalidate_device(struct block_device *bdev) { @@ -1430,7 +1403,7 @@ int __invalidate_device(struct block_device *bdev) res = invalidate_inodes(sb); drop_super(sb); } - invalidate_bdev(bdev, 0); + invalidate_bdev(bdev); return res; } EXPORT_SYMBOL(__invalidate_device);