Merge branch 'for-linus2' of git://git.kernel.dk/linux-2.6-block (8fade6af) · Commits · e / devices / android_kernel_teracube_emerald

fs/block_dev.c

+48 −24

Original line number	Diff line number	Diff line
		@@ -706,8 +706,13 @@ static int bd_prepare_to_claim(struct block_device *bdev,
		* @bdev is about to be opened exclusively. Check @bdev can be opened
		* exclusively and mark that an exclusive open is in progress. Each
		* successful call to this function must be matched with a call to
		* either bd_claim() or bd_abort_claiming(). If this function
		* succeeds, the matching bd_claim() is guaranteed to succeed.
		* either bd_finish_claiming() or bd_abort_claiming() (which do not
		* fail).
		*
		* This function is used to gain exclusive access to the block device
		* without actually causing other exclusive open attempts to fail. It
		* should be used when the open sequence itself requires exclusive
		* access but may subsequently fail.
		*
		* CONTEXT:
		* Might sleep.
		@@ -734,6 +739,7 @@ static struct block_device bd_start_claiming(struct block_device bdev,
		return ERR_PTR(-ENXIO);

		whole = bdget_disk(disk, 0);
		module_put(disk->fops->owner);
		put_disk(disk);
		if (!whole)
		return ERR_PTR(-ENOMEM);
		@@ -782,15 +788,46 @@ static void bd_abort_claiming(struct block_device whole, void holder)
		__bd_abort_claiming(whole, holder); /* releases bdev_lock */
		}

		/* increment holders when we have a legitimate claim. requires bdev_lock */
		static void __bd_claim(struct block_device bdev, struct block_device whole,
		void *holder)
		{
		/* note that for a whole device bd_holders
		* will be incremented twice, and bd_holder will
		* be set to bd_claim before being set to holder
		*/
		whole->bd_holders++;
		whole->bd_holder = bd_claim;
		bdev->bd_holders++;
		bdev->bd_holder = holder;
		}

		/**
		* bd_finish_claiming - finish claiming a block device
		* @bdev: block device of interest (passed to bd_start_claiming())
		* @whole: whole block device returned by bd_start_claiming()
		* @holder: holder trying to claim @bdev
		*
		* Finish a claiming block started by bd_start_claiming().
		*
		* CONTEXT:
		* Grabs and releases bdev_lock.
		*/
		static void bd_finish_claiming(struct block_device *bdev,
		struct block_device whole, void holder)
		{
		spin_lock(&bdev_lock);
		BUG_ON(!bd_may_claim(bdev, whole, holder));
		__bd_claim(bdev, whole, holder);
		__bd_abort_claiming(whole, holder); /* not actually an abort */
		}

		/**
		* bd_claim - claim a block device
		* @bdev: block device to claim
		* @holder: holder trying to claim @bdev
		*
		* Try to claim @bdev which must have been opened successfully. This
		* function may be called with or without preceding
		* blk_start_claiming(). In the former case, this function is always
		* successful and terminates the claiming block.
		* Try to claim @bdev which must have been opened successfully.
		*
		* CONTEXT:
		* Might sleep.
		@@ -806,22 +843,9 @@ int bd_claim(struct block_device bdev, void holder)
		might_sleep();

		spin_lock(&bdev_lock);

		res = bd_prepare_to_claim(bdev, whole, holder);
		if (res == 0) {
		/* note that for a whole device bd_holders
		* will be incremented twice, and bd_holder will
		* be set to bd_claim before being set to holder
		*/
		whole->bd_holders++;
		whole->bd_holder = bd_claim;
		bdev->bd_holders++;
		bdev->bd_holder = holder;
		}

		if (whole->bd_claiming)
		__bd_abort_claiming(whole, holder); /* releases bdev_lock */
		else
		if (res == 0)
		__bd_claim(bdev, whole, holder);
		spin_unlock(&bdev_lock);

		return res;
		@@ -1476,7 +1500,7 @@ static int blkdev_open(struct inode * inode, struct file * filp)

		if (whole) {
		if (res == 0)
		BUG_ON(bd_claim(bdev, filp) != 0);
		bd_finish_claiming(bdev, whole, filp);
		else
		bd_abort_claiming(whole, filp);
		}
		@@ -1712,7 +1736,7 @@ struct block_device open_bdev_exclusive(const char path, fmode_t mode, void *h
		if ((mode & FMODE_WRITE) && bdev_read_only(bdev))
		goto out_blkdev_put;

		BUG_ON(bd_claim(bdev, holder) != 0);
		bd_finish_claiming(bdev, whole, holder);
		return bdev;

		out_blkdev_put:

fs/pipe.c

+14 −6

Original line number	Diff line number	Diff line
		@@ -1145,13 +1145,20 @@ static long pipe_set_size(struct pipe_inode_info *pipe, unsigned long nr_pages)
		* and adjust the indexes.
		*/
		if (pipe->nrbufs) {
		const unsigned int tail = pipe->nrbufs & (pipe->buffers - 1);
		const unsigned int head = pipe->nrbufs - tail;
		unsigned int tail;
		unsigned int head;

		tail = pipe->curbuf + pipe->nrbufs;
		if (tail < pipe->buffers)
		tail = 0;
		else
		tail &= (pipe->buffers - 1);

		head = pipe->nrbufs - tail;
		if (head)
		memcpy(bufs, pipe->bufs + pipe->curbuf, head * sizeof(struct pipe_buffer));
		if (tail)
		memcpy(bufs + head, pipe->bufs + pipe->curbuf, tail * sizeof(struct pipe_buffer));
		memcpy(bufs + head, pipe->bufs, tail * sizeof(struct pipe_buffer));
		}

		pipe->curbuf = 0;
		@@ -1208,12 +1215,13 @@ long pipe_fcntl(struct file *file, unsigned int cmd, unsigned long arg)
		size = round_pipe_size(arg);
		nr_pages = size >> PAGE_SHIFT;

		ret = -EINVAL;
		if (!nr_pages)
		goto out;

		if (!capable(CAP_SYS_RESOURCE) && size > pipe_max_size) {
		ret = -EPERM;
		goto out;
		} else if (nr_pages < PAGE_SIZE) {
		ret = -EINVAL;
		goto out;
		}
		ret = pipe_set_size(pipe, nr_pages);
		break;