X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=drivers%2Fblock%2Floop.c;h=91ebb007416c185587b22ac08e46993f09fcb7dc;hb=877c357e7511395bc923ec9efc2e8b021a17ed79;hp=b9233a06934c08d18f962e578c9c2fbc7c7b3ae8;hpb=e3d18658d4f28e4783e1bb1c41e9134c9e5db0a9;p=linux-2.6 diff --git a/drivers/block/loop.c b/drivers/block/loop.c index b9233a0693..91ebb00741 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -29,7 +29,7 @@ * * Maximum number of loop devices when compiled-in now selectable by passing * max_loop=<1-255> to the kernel on boot. - * Erik I. Bolsø, , Oct 31, 1999 + * Erik I. Bolsø, , Oct 31, 1999 * * Completely rewrite request handling to be make_request_fn style and * non blocking, pushing work to a helper thread. Lots of fixes from @@ -204,14 +204,13 @@ lo_do_transfer(struct loop_device *lo, int cmd, * do_lo_send_aops - helper for writing data to a loop device * * This is the fast version for backing filesystems which implement the address - * space operations prepare_write and commit_write. + * space operations write_begin and write_end. */ static int do_lo_send_aops(struct loop_device *lo, struct bio_vec *bvec, - int bsize, loff_t pos, struct page *page) + int bsize, loff_t pos, struct page *unused) { struct file *file = lo->lo_backing_file; /* kudos to NFsckingS */ struct address_space *mapping = file->f_mapping; - const struct address_space_operations *aops = mapping->a_ops; pgoff_t index; unsigned offset, bv_offs; int len, ret; @@ -223,63 +222,45 @@ static int do_lo_send_aops(struct loop_device *lo, struct bio_vec *bvec, len = bvec->bv_len; while (len > 0) { sector_t IV; - unsigned size; + unsigned size, copied; int transfer_result; + struct page *page; + void *fsdata; IV = ((sector_t)index << (PAGE_CACHE_SHIFT - 9))+(offset >> 9); size = PAGE_CACHE_SIZE - offset; if (size > len) size = len; - page = grab_cache_page(mapping, index); - if (unlikely(!page)) + + ret = pagecache_write_begin(file, mapping, pos, size, 0, + &page, &fsdata); + if (ret) goto fail; - ret = aops->prepare_write(file, page, offset, - offset + size); - if (unlikely(ret)) { - if (ret == AOP_TRUNCATED_PAGE) { - page_cache_release(page); - continue; - } - goto unlock; - } + transfer_result = lo_do_transfer(lo, WRITE, page, offset, bvec->bv_page, bv_offs, size, IV); - if (unlikely(transfer_result)) { - /* - * The transfer failed, but we still write the data to - * keep prepare/commit calls balanced. - */ - printk(KERN_ERR "loop: transfer error block %llu\n", - (unsigned long long)index); - zero_user_page(page, offset, size, KM_USER0); - } - flush_dcache_page(page); - ret = aops->commit_write(file, page, offset, - offset + size); - if (unlikely(ret)) { - if (ret == AOP_TRUNCATED_PAGE) { - page_cache_release(page); - continue; - } - goto unlock; - } + copied = size; if (unlikely(transfer_result)) - goto unlock; - bv_offs += size; - len -= size; + copied = 0; + + ret = pagecache_write_end(file, mapping, pos, size, copied, + page, fsdata); + if (ret < 0 || ret != copied) + goto fail; + + if (unlikely(transfer_result)) + goto fail; + + bv_offs += copied; + len -= copied; offset = 0; index++; - pos += size; - unlock_page(page); - page_cache_release(page); + pos += copied; } ret = 0; out: mutex_unlock(&mapping->host->i_mutex); return ret; -unlock: - unlock_page(page); - page_cache_release(page); fail: ret = -1; goto out; @@ -313,7 +294,7 @@ static int __do_lo_send_write(struct file *file, * do_lo_send_direct_write - helper for writing data to a loop device * * This is the fast, non-transforming version for backing filesystems which do - * not implement the address space operations prepare_write and commit_write. + * not implement the address space operations write_begin and write_end. * It uses the write file operation which should be present on all writeable * filesystems. */ @@ -332,7 +313,7 @@ static int do_lo_send_direct_write(struct loop_device *lo, * do_lo_send_write - helper for writing data to a loop device * * This is the slow, transforming version for filesystems which do not - * implement the address space operations prepare_write and commit_write. It + * implement the address space operations write_begin and write_end. It * uses the write file operation which should be present on all writeable * filesystems. * @@ -629,7 +610,7 @@ static int loop_thread(void *data) static int loop_switch(struct loop_device *lo, struct file *file) { struct switch_request w; - struct bio *bio = bio_alloc(GFP_KERNEL, 1); + struct bio *bio = bio_alloc(GFP_KERNEL, 0); if (!bio) return -ENOMEM; init_completion(&w.wait); @@ -780,7 +761,7 @@ static int loop_set_fd(struct loop_device *lo, struct file *lo_file, */ if (!file->f_op->splice_read) goto out_putf; - if (aops->prepare_write && aops->commit_write) + if (aops->prepare_write || aops->write_begin) lo_flags |= LO_FLAGS_USE_AOPS; if (!(lo_flags & LO_FLAGS_USE_AOPS) && !file->f_op->write) lo_flags |= LO_FLAGS_READ_ONLY; @@ -992,6 +973,10 @@ loop_set_status(struct loop_device *lo, const struct loop_info64 *info) lo->transfer = xfer->transfer; lo->ioctl = xfer->ioctl; + if ((lo->lo_flags & LO_FLAGS_AUTOCLEAR) != + (info->lo_flags & LO_FLAGS_AUTOCLEAR)) + lo->lo_flags ^= LO_FLAGS_AUTOCLEAR; + lo->lo_encrypt_key_size = info->lo_encrypt_key_size; lo->lo_init[0] = info->lo_init[0]; lo->lo_init[1] = info->lo_init[1]; @@ -1304,7 +1289,6 @@ static long lo_compat_ioctl(struct file *file, unsigned int cmd, unsigned long a struct loop_device *lo = inode->i_bdev->bd_disk->private_data; int err; - lock_kernel(); switch(cmd) { case LOOP_SET_STATUS: mutex_lock(&lo->lo_ctl_mutex); @@ -1330,7 +1314,6 @@ static long lo_compat_ioctl(struct file *file, unsigned int cmd, unsigned long a err = -ENOIOCTLCMD; break; } - unlock_kernel(); return err; } #endif @@ -1352,6 +1335,10 @@ static int lo_release(struct inode *inode, struct file *file) mutex_lock(&lo->lo_ctl_mutex); --lo->lo_refcnt; + + if ((lo->lo_flags & LO_FLAGS_AUTOCLEAR) && !lo->lo_refcnt) + loop_clr_fd(lo, inode->i_bdev); + mutex_unlock(&lo->lo_ctl_mutex); return 0;