return 0;
}
-static int
-pipe_iov_copy_to_user(struct iovec *iov, const void *from, unsigned long len,
- int atomic)
-{
- unsigned long copy;
-
- while (len > 0) {
- while (!iov->iov_len)
- iov++;
- copy = min_t(unsigned long, len, iov->iov_len);
-
- if (atomic) {
- if (__copy_to_user_inatomic(iov->iov_base, from, copy))
- return -EFAULT;
- } else {
- if (copy_to_user(iov->iov_base, from, copy))
- return -EFAULT;
- }
- from += copy;
- len -= copy;
- iov->iov_base += copy;
- iov->iov_len -= copy;
- }
- return 0;
-}
-
-/*
- * Attempt to pre-fault in the user memory, so we can use atomic copies.
- * Returns the number of bytes not faulted in.
- */
-static int iov_fault_in_pages_write(struct iovec *iov, unsigned long len)
-{
- while (!iov->iov_len)
- iov++;
-
- while (len > 0) {
- unsigned long this_len;
-
- this_len = min_t(unsigned long, len, iov->iov_len);
- if (fault_in_pages_writeable(iov->iov_base, this_len))
- break;
-
- len -= this_len;
- iov++;
- }
-
- return len;
-}
-
/*
* Pre-fault in the user memory, so we can use atomic copies.
*/
page_cache_release(page);
}
-/**
- * generic_pipe_buf_map - virtually map a pipe buffer
- * @pipe: the pipe that the buffer belongs to
- * @buf: the buffer that should be mapped
- * @atomic: whether to use an atomic map
- *
- * Description:
- * This function returns a kernel virtual address mapping for the
- * pipe_buffer passed in @buf. If @atomic is set, an atomic map is provided
- * and the caller has to be careful not to fault before calling
- * the unmap function.
- *
- * Note that this function calls kmap_atomic() if @atomic != 0.
- */
-void *generic_pipe_buf_map(struct pipe_inode_info *pipe,
- struct pipe_buffer *buf, int atomic)
-{
- if (atomic) {
- buf->flags |= PIPE_BUF_FLAG_ATOMIC;
- return kmap_atomic(buf->page);
- }
-
- return kmap(buf->page);
-}
-EXPORT_SYMBOL(generic_pipe_buf_map);
-
-/**
- * generic_pipe_buf_unmap - unmap a previously mapped pipe buffer
- * @pipe: the pipe that the buffer belongs to
- * @buf: the buffer that should be unmapped
- * @map_data: the data that the mapping function returned
- *
- * Description:
- * This function undoes the mapping that ->map() provided.
- */
-void generic_pipe_buf_unmap(struct pipe_inode_info *pipe,
- struct pipe_buffer *buf, void *map_data)
-{
- if (buf->flags & PIPE_BUF_FLAG_ATOMIC) {
- buf->flags &= ~PIPE_BUF_FLAG_ATOMIC;
- kunmap_atomic(map_data);
- } else
- kunmap(buf->page);
-}
-EXPORT_SYMBOL(generic_pipe_buf_unmap);
-
/**
* generic_pipe_buf_steal - attempt to take ownership of a &pipe_buffer
* @pipe: the pipe that the buffer belongs to
static const struct pipe_buf_operations anon_pipe_buf_ops = {
.can_merge = 1,
- .map = generic_pipe_buf_map,
- .unmap = generic_pipe_buf_unmap,
.confirm = generic_pipe_buf_confirm,
.release = anon_pipe_buf_release,
.steal = generic_pipe_buf_steal,
static const struct pipe_buf_operations packet_pipe_buf_ops = {
.can_merge = 0,
- .map = generic_pipe_buf_map,
- .unmap = generic_pipe_buf_unmap,
.confirm = generic_pipe_buf_confirm,
.release = anon_pipe_buf_release,
.steal = generic_pipe_buf_steal,
ssize_t ret;
struct iovec *iov = (struct iovec *)_iov;
size_t total_len;
+ struct iov_iter iter;
total_len = iov_length(iov, nr_segs);
/* Null read succeeds. */
if (unlikely(total_len == 0))
return 0;
+ iov_iter_init(&iter, iov, nr_segs, total_len, 0);
+
do_wakeup = 0;
ret = 0;
__pipe_lock(pipe);
int curbuf = pipe->curbuf;
struct pipe_buffer *buf = pipe->bufs + curbuf;
const struct pipe_buf_operations *ops = buf->ops;
- void *addr;
size_t chars = buf->len;
- int error, atomic;
+ size_t written;
+ int error;
if (chars > total_len)
chars = total_len;
break;
}
- atomic = !iov_fault_in_pages_write(iov, chars);
-redo:
- addr = ops->map(pipe, buf, atomic);
- error = pipe_iov_copy_to_user(iov, addr + buf->offset, chars, atomic);
- ops->unmap(pipe, buf, addr);
- if (unlikely(error)) {
- /*
- * Just retry with the slow path if we failed.
- */
- if (atomic) {
- atomic = 0;
- goto redo;
- }
+ written = copy_page_to_iter(buf->page, buf->offset, chars, &iter);
+ if (unlikely(written < chars)) {
if (!ret)
- ret = error;
+ ret = -EFAULT;
break;
}
ret += chars;
iov_fault_in_pages_read(iov, chars);
redo1:
- addr = ops->map(pipe, buf, atomic);
+ if (atomic)
+ addr = kmap_atomic(buf->page);
+ else
+ addr = kmap(buf->page);
error = pipe_iov_copy_from_user(offset + addr, iov,
chars, atomic);
- ops->unmap(pipe, buf, addr);
+ if (atomic)
+ kunmap_atomic(addr);
+ else
+ kunmap(buf->page);
ret = error;
do_wakeup = 1;
if (error) {
projects / linux.git / blobdiff