Merge branch 'tee' of git://brick.kernel.dk/data/git/linux-2.6-block (9ca68662) · Commits · EulixOS / Software / Kernel

arch/i386/kernel/syscall_table.S

+1 −0

Original line number	Diff line number	Diff line
		@@ -314,3 +314,4 @@ ENTRY(sys_call_table)
		.long sys_get_robust_list
		.long sys_splice
		.long sys_sync_file_range
		.long sys_tee /* 315 */

arch/ia64/kernel/entry.S

+1 −0

Original line number	Diff line number	Diff line
		@@ -1609,5 +1609,6 @@ sys_call_table:
		data8 sys_set_robust_list
		data8 sys_get_robust_list
		data8 sys_sync_file_range // 1300
		data8 sys_tee

		.org sys_call_table + 8*NR_syscalls // guard against failures to increase NR_syscalls

arch/powerpc/kernel/systbl.S

+1 −0

Original line number	Diff line number	Diff line
		@@ -323,3 +323,4 @@ COMPAT_SYS(pselect6)
		COMPAT_SYS(ppoll)
		SYSCALL(unshare)
		SYSCALL(splice)
		SYSCALL(tee)

fs/pipe.c

+7 −0

Original line number	Diff line number	Diff line
		@@ -131,12 +131,19 @@ static int anon_pipe_buf_steal(struct pipe_inode_info *pipe,
		return 0;
		}

		static void anon_pipe_buf_get(struct pipe_inode_info *info,
		struct pipe_buffer *buf)
		{
		page_cache_get(buf->page);
		}

		static struct pipe_buf_operations anon_pipe_buf_ops = {
		.can_merge = 1,
		.map = anon_pipe_buf_map,
		.unmap = anon_pipe_buf_unmap,
		.release = anon_pipe_buf_release,
		.steal = anon_pipe_buf_steal,
		.get = anon_pipe_buf_get,
		};

		static ssize_t

fs/splice.c

+230 −42

Original line number	Diff line number	Diff line
		@@ -125,12 +125,19 @@ static void page_cache_pipe_buf_unmap(struct pipe_inode_info *info,
		kunmap(buf->page);
		}

		static void page_cache_pipe_buf_get(struct pipe_inode_info *info,
		struct pipe_buffer *buf)
		{
		page_cache_get(buf->page);
		}

		static struct pipe_buf_operations page_cache_pipe_buf_ops = {
		.can_merge = 0,
		.map = page_cache_pipe_buf_map,
		.unmap = page_cache_pipe_buf_unmap,
		.release = page_cache_pipe_buf_release,
		.steal = page_cache_pipe_buf_steal,
		.get = page_cache_pipe_buf_get,
		};

		/*
		@@ -231,8 +238,9 @@ static ssize_t move_to_pipe(struct pipe_inode_info pipe, struct page *pages,
		}

		static int
		__generic_file_splice_read(struct file in, struct pipe_inode_info pipe,
		size_t len, unsigned int flags)
		__generic_file_splice_read(struct file in, loff_t ppos,
		struct pipe_inode_info *pipe, size_t len,
		unsigned int flags)
		{
		struct address_space *mapping = in->f_mapping;
		unsigned int offset, nr_pages;
		@@ -241,8 +249,8 @@ __generic_file_splice_read(struct file in, struct pipe_inode_info pipe,
		pgoff_t index;
		int i, error;

		index = in->f_pos >> PAGE_CACHE_SHIFT;
		offset = in->f_pos & ~PAGE_CACHE_MASK;
		index = *ppos >> PAGE_CACHE_SHIFT;
		offset = *ppos & ~PAGE_CACHE_MASK;
		nr_pages = (len + offset + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;

		if (nr_pages > PIPE_BUFFERS)
		@@ -348,8 +356,9 @@ __generic_file_splice_read(struct file in, struct pipe_inode_info pipe,
		*
		* Will read pages from given file and fill them into a pipe.
		*/
		ssize_t generic_file_splice_read(struct file in, struct pipe_inode_info pipe,
		size_t len, unsigned int flags)
		ssize_t generic_file_splice_read(struct file in, loff_t ppos,
		struct pipe_inode_info *pipe, size_t len,
		unsigned int flags)
		{
		ssize_t spliced;
		int ret;
		@@ -358,12 +367,12 @@ ssize_t generic_file_splice_read(struct file in, struct pipe_inode_info pipe,
		spliced = 0;

		while (len) {
		ret = __generic_file_splice_read(in, pipe, len, flags);
		ret = __generic_file_splice_read(in, ppos, pipe, len, flags);

		if (ret <= 0)
		break;

		in->f_pos += ret;
		*ppos += ret;
		len -= ret;
		spliced += ret;

		@@ -561,7 +570,7 @@ typedef int (splice_actor)(struct pipe_inode_info , struct pipe_buffer ,
		* to the wanted destination. See pipe_to_file/pipe_to_sendpage above.
		*/
		static ssize_t move_from_pipe(struct pipe_inode_info pipe, struct file out,
		size_t len, unsigned int flags,
		loff_t *ppos, size_t len, unsigned int flags,
		splice_actor *actor)
		{
		int ret, do_wakeup, err;
		@@ -573,7 +582,7 @@ static ssize_t move_from_pipe(struct pipe_inode_info pipe, struct file out,
		sd.total_len = len;
		sd.flags = flags;
		sd.file = out;
		sd.pos = out->f_pos;
		sd.pos = *ppos;

		if (pipe->inode)
		mutex_lock(&pipe->inode->i_mutex);
		@@ -656,9 +665,7 @@ static ssize_t move_from_pipe(struct pipe_inode_info pipe, struct file out,
		kill_fasync(&pipe->fasync_writers, SIGIO, POLL_OUT);
		}

		out->f_pos = sd.pos;
		return ret;

		}

		/**
		@@ -674,12 +681,12 @@ static ssize_t move_from_pipe(struct pipe_inode_info pipe, struct file out,
		*/
		ssize_t
		generic_file_splice_write(struct pipe_inode_info pipe, struct file out,
		size_t len, unsigned int flags)
		loff_t *ppos, size_t len, unsigned int flags)
		{
		struct address_space *mapping = out->f_mapping;
		ssize_t ret;

		ret = move_from_pipe(pipe, out, len, flags, pipe_to_file);
		ret = move_from_pipe(pipe, out, ppos, len, flags, pipe_to_file);

		/*
		* If file or inode is SYNC and we actually wrote some data, sync it.
		@@ -715,9 +722,9 @@ EXPORT_SYMBOL(generic_file_splice_write);
		*
		*/
		ssize_t generic_splice_sendpage(struct pipe_inode_info pipe, struct file out,
		size_t len, unsigned int flags)
		loff_t *ppos, size_t len, unsigned int flags)
		{
		return move_from_pipe(pipe, out, len, flags, pipe_to_sendpage);
		return move_from_pipe(pipe, out, ppos, len, flags, pipe_to_sendpage);
		}

		EXPORT_SYMBOL(generic_splice_sendpage);
		@@ -726,9 +733,8 @@ EXPORT_SYMBOL(generic_splice_sendpage);
		* Attempt to initiate a splice from pipe to file.
		*/
		static long do_splice_from(struct pipe_inode_info pipe, struct file out,
		size_t len, unsigned int flags)
		loff_t *ppos, size_t len, unsigned int flags)
		{
		loff_t pos;
		int ret;

		if (unlikely(!out->f_op \|\| !out->f_op->splice_write))
		@@ -737,22 +743,21 @@ static long do_splice_from(struct pipe_inode_info pipe, struct file out,
		if (unlikely(!(out->f_mode & FMODE_WRITE)))
		return -EBADF;

		pos = out->f_pos;

		ret = rw_verify_area(WRITE, out, &pos, len);
		ret = rw_verify_area(WRITE, out, ppos, len);
		if (unlikely(ret < 0))
		return ret;

		return out->f_op->splice_write(pipe, out, len, flags);
		return out->f_op->splice_write(pipe, out, ppos, len, flags);
		}

		/*
		* Attempt to initiate a splice from a file to a pipe.
		*/
		static long do_splice_to(struct file in, struct pipe_inode_info pipe,
		size_t len, unsigned int flags)
		static long do_splice_to(struct file in, loff_t ppos,
		struct pipe_inode_info *pipe, size_t len,
		unsigned int flags)
		{
		loff_t pos, isize, left;
		loff_t isize, left;
		int ret;

		if (unlikely(!in->f_op \|\| !in->f_op->splice_read))
		@@ -761,28 +766,27 @@ static long do_splice_to(struct file in, struct pipe_inode_info pipe,
		if (unlikely(!(in->f_mode & FMODE_READ)))
		return -EBADF;

		pos = in->f_pos;

		ret = rw_verify_area(READ, in, &pos, len);
		ret = rw_verify_area(READ, in, ppos, len);
		if (unlikely(ret < 0))
		return ret;

		isize = i_size_read(in->f_mapping->host);
		if (unlikely(in->f_pos >= isize))
		if (unlikely(*ppos >= isize))
		return 0;

		left = isize - in->f_pos;
		left = isize - *ppos;
		if (unlikely(left < len))
		len = left;

		return in->f_op->splice_read(in, pipe, len, flags);
		return in->f_op->splice_read(in, ppos, pipe, len, flags);
		}

		long do_splice_direct(struct file in, struct file out, size_t len,
		unsigned int flags)
		long do_splice_direct(struct file in, loff_t ppos, struct file *out,
		size_t len, unsigned int flags)
		{
		struct pipe_inode_info *pipe;
		long ret, bytes;
		loff_t out_off;
		umode_t i_mode;
		int i;

		@@ -820,6 +824,7 @@ long do_splice_direct(struct file in, struct file out, size_t len,
		*/
		ret = 0;
		bytes = 0;
		out_off = 0;

		while (len) {
		size_t read_len, max_read_len;
		@@ -829,7 +834,7 @@ long do_splice_direct(struct file in, struct file out, size_t len,
		*/
		max_read_len = min(len, (size_t)(PIPE_BUFFERS*PAGE_SIZE));

		ret = do_splice_to(in, pipe, max_read_len, flags);
		ret = do_splice_to(in, ppos, pipe, max_read_len, flags);
		if (unlikely(ret < 0))
		goto out_release;

		@@ -840,7 +845,7 @@ long do_splice_direct(struct file in, struct file out, size_t len,
		* must not do the output in nonblocking mode as then we
		* could get stuck data in the internal pipe:
		*/
		ret = do_splice_from(pipe, out, read_len,
		ret = do_splice_from(pipe, out, &out_off, read_len,
		flags & ~SPLICE_F_NONBLOCK);
		if (unlikely(ret < 0))
		goto out_release;
		@@ -898,6 +903,7 @@ static long do_splice(struct file in, loff_t __user off_in,
		size_t len, unsigned int flags)
		{
		struct pipe_inode_info *pipe;
		loff_t offset, *off;

		pipe = in->f_dentry->d_inode->i_pipe;
		if (pipe) {
		@@ -906,12 +912,13 @@ static long do_splice(struct file in, loff_t __user off_in,
		if (off_out) {
		if (out->f_op->llseek == no_llseek)
		return -EINVAL;
		if (copy_from_user(&out->f_pos, off_out,
		sizeof(loff_t)))
		if (copy_from_user(&offset, off_out, sizeof(loff_t)))
		return -EFAULT;
		}
		off = &offset;
		} else
		off = &out->f_pos;

		return do_splice_from(pipe, out, len, flags);
		return do_splice_from(pipe, out, off, len, flags);
		}

		pipe = out->f_dentry->d_inode->i_pipe;
		@@ -921,11 +928,13 @@ static long do_splice(struct file in, loff_t __user off_in,
		if (off_in) {
		if (in->f_op->llseek == no_llseek)
		return -EINVAL;
		if (copy_from_user(&in->f_pos, off_in, sizeof(loff_t)))
		if (copy_from_user(&offset, off_in, sizeof(loff_t)))
		return -EFAULT;
		}
		off = &offset;
		} else
		off = &in->f_pos;

		return do_splice_to(in, pipe, len, flags);
		return do_splice_to(in, off, pipe, len, flags);
		}

		return -EINVAL;
		@@ -961,3 +970,182 @@ asmlinkage long sys_splice(int fd_in, loff_t __user *off_in,

		return error;
		}

		/*
		* Link contents of ipipe to opipe.
		*/
		static int link_pipe(struct pipe_inode_info *ipipe,
		struct pipe_inode_info *opipe,
		size_t len, unsigned int flags)
		{
		struct pipe_buffer ibuf, obuf;
		int ret = 0, do_wakeup = 0, i;

		/*
		* Potential ABBA deadlock, work around it by ordering lock
		* grabbing by inode address. Otherwise two different processes
		* could deadlock (one doing tee from A -> B, the other from B -> A).
		*/
		if (ipipe->inode < opipe->inode) {
		mutex_lock(&ipipe->inode->i_mutex);
		mutex_lock(&opipe->inode->i_mutex);
		} else {
		mutex_lock(&opipe->inode->i_mutex);
		mutex_lock(&ipipe->inode->i_mutex);
		}

		for (i = 0;; i++) {
		if (!opipe->readers) {
		send_sig(SIGPIPE, current, 0);
		if (!ret)
		ret = -EPIPE;
		break;
		}
		if (ipipe->nrbufs - i) {
		ibuf = ipipe->bufs + ((ipipe->curbuf + i) & (PIPE_BUFFERS - 1));

		/*
		* If we have room, fill this buffer
		*/
		if (opipe->nrbufs < PIPE_BUFFERS) {
		int nbuf = (opipe->curbuf + opipe->nrbufs) & (PIPE_BUFFERS - 1);

		/*
		* Get a reference to this pipe buffer,
		* so we can copy the contents over.
		*/
		ibuf->ops->get(ipipe, ibuf);

		obuf = opipe->bufs + nbuf;
		obuf = ibuf;

		if (obuf->len > len)
		obuf->len = len;

		opipe->nrbufs++;
		do_wakeup = 1;
		ret += obuf->len;
		len -= obuf->len;

		if (!len)
		break;
		if (opipe->nrbufs < PIPE_BUFFERS)
		continue;
		}

		/*
		* We have input available, but no output room.
		* If we already copied data, return that.
		*/
		if (flags & SPLICE_F_NONBLOCK) {
		if (!ret)
		ret = -EAGAIN;
		break;
		}
		if (signal_pending(current)) {
		if (!ret)
		ret = -ERESTARTSYS;
		break;
		}
		if (do_wakeup) {
		smp_mb();
		if (waitqueue_active(&opipe->wait))
		wake_up_interruptible(&opipe->wait);
		kill_fasync(&opipe->fasync_readers, SIGIO, POLL_IN);
		do_wakeup = 0;
		}

		opipe->waiting_writers++;
		pipe_wait(opipe);
		opipe->waiting_writers--;
		continue;
		}

		/*
		* No input buffers, do the usual checks for available
		* writers and blocking and wait if necessary
		*/
		if (!ipipe->writers)
		break;
		if (!ipipe->waiting_writers) {
		if (ret)
		break;
		}
		if (flags & SPLICE_F_NONBLOCK) {
		if (!ret)
		ret = -EAGAIN;
		break;
		}
		if (signal_pending(current)) {
		if (!ret)
		ret = -ERESTARTSYS;
		break;
		}

		if (waitqueue_active(&ipipe->wait))
		wake_up_interruptible_sync(&ipipe->wait);
		kill_fasync(&ipipe->fasync_writers, SIGIO, POLL_OUT);

		pipe_wait(ipipe);
		}

		mutex_unlock(&ipipe->inode->i_mutex);
		mutex_unlock(&opipe->inode->i_mutex);

		if (do_wakeup) {
		smp_mb();
		if (waitqueue_active(&opipe->wait))
		wake_up_interruptible(&opipe->wait);
		kill_fasync(&opipe->fasync_readers, SIGIO, POLL_IN);
		}

		return ret;
		}

		/*
		* This is a tee(1) implementation that works on pipes. It doesn't copy
		* any data, it simply references the 'in' pages on the 'out' pipe.
		* The 'flags' used are the SPLICE_F_* variants, currently the only
		* applicable one is SPLICE_F_NONBLOCK.
		*/
		static long do_tee(struct file in, struct file out, size_t len,
		unsigned int flags)
		{
		struct pipe_inode_info *ipipe = in->f_dentry->d_inode->i_pipe;
		struct pipe_inode_info *opipe = out->f_dentry->d_inode->i_pipe;

		/*
		* Link ipipe to the two output pipes, consuming as we go along.
		*/
		if (ipipe && opipe)
		return link_pipe(ipipe, opipe, len, flags);

		return -EINVAL;
		}

		asmlinkage long sys_tee(int fdin, int fdout, size_t len, unsigned int flags)
		{
		struct file *in;
		int error, fput_in;

		if (unlikely(!len))
		return 0;

		error = -EBADF;
		in = fget_light(fdin, &fput_in);
		if (in) {
		if (in->f_mode & FMODE_READ) {
		int fput_out;
		struct file *out = fget_light(fdout, &fput_out);

		if (out) {
		if (out->f_mode & FMODE_WRITE)
		error = do_tee(in, out, len, flags);
		fput_light(out, fput_out);
		}
		}
		fput_light(in, fput_in);
		}

		return error;
		}