X-Git-Url: http://pilppa.org/gitweb/?a=blobdiff_plain;f=drivers%2Fblock%2Floop.c;h=5c4ee70d5cf319311deab818996928af5f2736f6;hb=cdce1f0931831cebfbeb811a266a2f4adf5c8a35;hp=91ebb007416c185587b22ac08e46993f09fcb7dc;hpb=7924e4f6519dd5b349ed146fe9fe35206730be67;p=linux-2.6-omap-h63xx.git

diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 91ebb007416..5c4ee70d5cf 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -40,8 +40,7 @@
  * Heinz Mauelshagen <mge@sistina.com>, Feb 2002
  *
  * Support for falling back on the write file operation when the address space
- * operations prepare_write and/or commit_write are not available on the
- * backing filesystem.
+ * operations write_begin is not available on the backing filesystem.
  * Anton Altaparmakov, 16 Feb 2005
  *
  * Still To Fix:
@@ -82,6 +81,9 @@
 static LIST_HEAD(loop_devices);
 static DEFINE_MUTEX(loop_devices_mutex);
 
+static int max_part;
+static int part_shift;
+
 /*
  * Transfer functions
  */
@@ -207,7 +209,7 @@ lo_do_transfer(struct loop_device *lo, int cmd,
  * 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 *unused)
+		loff_t pos, struct page *unused)
 {
 	struct file *file = lo->lo_backing_file; /* kudos to NFsckingS */
 	struct address_space *mapping = file->f_mapping;
@@ -299,7 +301,7 @@ static int __do_lo_send_write(struct file *file,
  * filesystems.
  */
 static int do_lo_send_direct_write(struct loop_device *lo,
-		struct bio_vec *bvec, int bsize, loff_t pos, struct page *page)
+		struct bio_vec *bvec, loff_t pos, struct page *page)
 {
 	ssize_t bw = __do_lo_send_write(lo->lo_backing_file,
 			kmap(bvec->bv_page) + bvec->bv_offset,
@@ -323,7 +325,7 @@ static int do_lo_send_direct_write(struct loop_device *lo,
  * destination pages of the backing file.
  */
 static int do_lo_send_write(struct loop_device *lo, struct bio_vec *bvec,
-		int bsize, loff_t pos, struct page *page)
+		loff_t pos, struct page *page)
 {
 	int ret = lo_do_transfer(lo, WRITE, page, 0, bvec->bv_page,
 			bvec->bv_offset, bvec->bv_len, pos >> 9);
@@ -338,10 +340,9 @@ static int do_lo_send_write(struct loop_device *lo, struct bio_vec *bvec,
 	return ret;
 }
 
-static int lo_send(struct loop_device *lo, struct bio *bio, int bsize,
-		loff_t pos)
+static int lo_send(struct loop_device *lo, struct bio *bio, loff_t pos)
 {
-	int (*do_lo_send)(struct loop_device *, struct bio_vec *, int, loff_t,
+	int (*do_lo_send)(struct loop_device *, struct bio_vec *, loff_t,
 			struct page *page);
 	struct bio_vec *bvec;
 	struct page *page = NULL;
@@ -359,7 +360,7 @@ static int lo_send(struct loop_device *lo, struct bio *bio, int bsize,
 		}
 	}
 	bio_for_each_segment(bvec, bio, i) {
-		ret = do_lo_send(lo, bvec, bsize, pos, page);
+		ret = do_lo_send(lo, bvec, pos, page);
 		if (ret < 0)
 			break;
 		pos += bvec->bv_len;
@@ -475,7 +476,7 @@ static int do_bio_filebacked(struct loop_device *lo, struct bio *bio)
 
 	pos = ((loff_t) bio->bi_sector << 9) + lo->lo_offset;
 	if (bio_rw(bio) == WRITE)
-		ret = lo_send(lo, bio, lo->lo_blocksize, pos);
+		ret = lo_send(lo, bio, pos);
 	else
 		ret = lo_receive(lo, bio, lo->lo_blocksize, pos);
 	return ret;
@@ -543,7 +544,7 @@ static void loop_unplug(struct request_queue *q)
 {
 	struct loop_device *lo = q->queuedata;
 
-	clear_bit(QUEUE_FLAG_PLUGGED, &q->queue_flags);
+	queue_flag_clear_unlocked(QUEUE_FLAG_PLUGGED, q);
 	blk_run_address_space(lo->lo_backing_file->f_mapping);
 }
 
@@ -649,8 +650,8 @@ static void do_loop_switch(struct loop_device *lo, struct switch_request *p)
  * This can only work if the loop device is used read-only, and if the
  * new backing store is the same size and type as the old backing store.
  */
-static int loop_change_fd(struct loop_device *lo, struct file *lo_file,
-		       struct block_device *bdev, unsigned int arg)
+static int loop_change_fd(struct loop_device *lo, struct block_device *bdev,
+			  unsigned int arg)
 {
 	struct file	*file, *old_file;
 	struct inode	*inode;
@@ -692,6 +693,8 @@ static int loop_change_fd(struct loop_device *lo, struct file *lo_file,
 		goto out_putf;
 
 	fput(old_file);
+	if (max_part > 0)
+		ioctl_by_bdev(bdev, BLKRRPART, 0);
 	return 0;
 
  out_putf:
@@ -707,7 +710,7 @@ static inline int is_loop_device(struct file *file)
 	return i && S_ISBLK(i->i_mode) && MAJOR(i->i_rdev) == LOOP_MAJOR;
 }
 
-static int loop_set_fd(struct loop_device *lo, struct file *lo_file,
+static int loop_set_fd(struct loop_device *lo, fmode_t mode,
 		       struct block_device *bdev, unsigned int arg)
 {
 	struct file	*file, *f;
@@ -735,7 +738,7 @@ static int loop_set_fd(struct loop_device *lo, struct file *lo_file,
 	while (is_loop_device(f)) {
 		struct loop_device *l;
 
-		if (f->f_mapping->host->i_rdev == lo_file->f_mapping->host->i_rdev)
+		if (f->f_mapping->host->i_bdev == bdev)
 			goto out_putf;
 
 		l = f->f_mapping->host->i_bdev->bd_disk->private_data;
@@ -761,7 +764,7 @@ 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->write_begin)
+		if (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;
@@ -781,7 +784,7 @@ static int loop_set_fd(struct loop_device *lo, struct file *lo_file,
 		goto out_putf;
 	}
 
-	if (!(lo_file->f_mode & FMODE_WRITE))
+	if (!(mode & FMODE_WRITE))
 		lo_flags |= LO_FLAGS_READ_ONLY;
 
 	set_device_ro(bdev, (lo_flags & LO_FLAGS_READ_ONLY) != 0);
@@ -819,6 +822,8 @@ static int loop_set_fd(struct loop_device *lo, struct file *lo_file,
 	}
 	lo->lo_state = Lo_bound;
 	wake_up_process(lo->lo_thread);
+	if (max_part > 0)
+		ioctl_by_bdev(bdev, BLKRRPART, 0);
 	return 0;
 
 out_clr:
@@ -911,14 +916,18 @@ static int loop_clr_fd(struct loop_device *lo, struct block_device *bdev)
 	memset(lo->lo_encrypt_key, 0, LO_KEY_SIZE);
 	memset(lo->lo_crypt_name, 0, LO_NAME_SIZE);
 	memset(lo->lo_file_name, 0, LO_NAME_SIZE);
-	invalidate_bdev(bdev);
+	if (bdev)
+		invalidate_bdev(bdev);
 	set_capacity(lo->lo_disk, 0);
-	bd_set_size(bdev, 0);
+	if (bdev)
+		bd_set_size(bdev, 0);
 	mapping_set_gfp_mask(filp->f_mapping, gfp);
 	lo->lo_state = Lo_unbound;
 	fput(filp);
 	/* This is safe: open() is still holding a reference. */
 	module_put(THIS_MODULE);
+	if (max_part > 0)
+		ioctl_by_bdev(bdev, BLKRRPART, 0);
 	return 0;
 }
 
@@ -1128,22 +1137,22 @@ loop_get_status64(struct loop_device *lo, struct loop_info64 __user *arg) {
 	return err;
 }
 
-static int lo_ioctl(struct inode * inode, struct file * file,
+static int lo_ioctl(struct block_device *bdev, fmode_t mode,
 	unsigned int cmd, unsigned long arg)
 {
-	struct loop_device *lo = inode->i_bdev->bd_disk->private_data;
+	struct loop_device *lo = bdev->bd_disk->private_data;
 	int err;
 
 	mutex_lock(&lo->lo_ctl_mutex);
 	switch (cmd) {
 	case LOOP_SET_FD:
-		err = loop_set_fd(lo, file, inode->i_bdev, arg);
+		err = loop_set_fd(lo, mode, bdev, arg);
 		break;
 	case LOOP_CHANGE_FD:
-		err = loop_change_fd(lo, file, inode->i_bdev, arg);
+		err = loop_change_fd(lo, bdev, arg);
 		break;
 	case LOOP_CLR_FD:
-		err = loop_clr_fd(lo, inode->i_bdev);
+		err = loop_clr_fd(lo, bdev);
 		break;
 	case LOOP_SET_STATUS:
 		err = loop_set_status_old(lo, (struct loop_info __user *) arg);
@@ -1283,10 +1292,10 @@ loop_get_status_compat(struct loop_device *lo,
 	return err;
 }
 
-static long lo_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static int lo_compat_ioctl(struct block_device *bdev, fmode_t mode,
+			   unsigned int cmd, unsigned long arg)
 {
-	struct inode *inode = file->f_path.dentry->d_inode;
-	struct loop_device *lo = inode->i_bdev->bd_disk->private_data;
+	struct loop_device *lo = bdev->bd_disk->private_data;
 	int err;
 
 	switch(cmd) {
@@ -1308,7 +1317,7 @@ static long lo_compat_ioctl(struct file *file, unsigned int cmd, unsigned long a
 		arg = (unsigned long) compat_ptr(arg);
 	case LOOP_SET_FD:
 	case LOOP_CHANGE_FD:
-		err = lo_ioctl(inode, file, cmd, arg);
+		err = lo_ioctl(bdev, mode, cmd, arg);
 		break;
 	default:
 		err = -ENOIOCTLCMD;
@@ -1318,9 +1327,9 @@ static long lo_compat_ioctl(struct file *file, unsigned int cmd, unsigned long a
 }
 #endif
 
-static int lo_open(struct inode *inode, struct file *file)
+static int lo_open(struct block_device *bdev, fmode_t mode)
 {
-	struct loop_device *lo = inode->i_bdev->bd_disk->private_data;
+	struct loop_device *lo = bdev->bd_disk->private_data;
 
 	mutex_lock(&lo->lo_ctl_mutex);
 	lo->lo_refcnt++;
@@ -1329,15 +1338,15 @@ static int lo_open(struct inode *inode, struct file *file)
 	return 0;
 }
 
-static int lo_release(struct inode *inode, struct file *file)
+static int lo_release(struct gendisk *disk, fmode_t mode)
 {
-	struct loop_device *lo = inode->i_bdev->bd_disk->private_data;
+	struct loop_device *lo = disk->private_data;
 
 	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);
+		loop_clr_fd(lo, NULL);
 
 	mutex_unlock(&lo->lo_ctl_mutex);
 
@@ -1360,6 +1369,8 @@ static struct block_device_operations lo_fops = {
 static int max_loop;
 module_param(max_loop, int, 0);
 MODULE_PARM_DESC(max_loop, "Maximum number of loop devices");
+module_param(max_part, int, 0);
+MODULE_PARM_DESC(max_part, "Maximum number of partitions per loop device");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS_BLOCKDEV_MAJOR(LOOP_MAJOR);
 
@@ -1412,7 +1423,7 @@ static struct loop_device *loop_alloc(int i)
 	if (!lo->lo_queue)
 		goto out_free_dev;
 
-	disk = lo->lo_disk = alloc_disk(1);
+	disk = lo->lo_disk = alloc_disk(1 << part_shift);
 	if (!disk)
 		goto out_free_queue;
 
@@ -1422,7 +1433,7 @@ static struct loop_device *loop_alloc(int i)
 	init_waitqueue_head(&lo->lo_event);
 	spin_lock_init(&lo->lo_lock);
 	disk->major		= LOOP_MAJOR;
-	disk->first_minor	= i;
+	disk->first_minor	= i << part_shift;
 	disk->fops		= &lo_fops;
 	disk->private_data	= lo;
 	disk->queue		= lo->lo_queue;
@@ -1502,7 +1513,12 @@ static int __init loop_init(void)
 	 *     themselves and have kernel automatically instantiate actual
 	 *     device on-demand.
 	 */
-	if (max_loop > 1UL << MINORBITS)
+
+	part_shift = 0;
+	if (max_part > 0)
+		part_shift = fls(max_part);
+
+	if (max_loop > 1UL << (MINORBITS - part_shift))
 		return -EINVAL;
 
 	if (max_loop) {
@@ -1510,7 +1526,7 @@ static int __init loop_init(void)
 		range = max_loop;
 	} else {
 		nr = 8;
-		range = 1UL << MINORBITS;
+		range = 1UL << (MINORBITS - part_shift);
 	}
 
 	if (register_blkdev(LOOP_MAJOR, "loop"))
@@ -1549,7 +1565,7 @@ static void __exit loop_exit(void)
 	unsigned long range;
 	struct loop_device *lo, *next;
 
-	range = max_loop ? max_loop :  1UL << MINORBITS;
+	range = max_loop ? max_loop :  1UL << (MINORBITS - part_shift);
 
 	list_for_each_entry_safe(lo, next, &loop_devices, lo_list)
 		loop_del_one(lo);