orangefs: make wait_for_direct_io() take iov_iter

incidentally, insane or compromised server returning *more* than
requested on read should not oops the kernel - initialize the
iov_iter for read according to the iovec we've got.  That's why
pvfs_bufmap_copy_to_iovec() needed a separate size argument - we
shouldn't abuse iov_iter_count(iter) for passing that.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
This commit is contained in:
Al Viro 2015-10-08 18:00:26 -04:00 committed by Mike Marshall
parent a5c126a522
commit 3c2fcfcb68

View File

@ -94,7 +94,7 @@ static int postcopy_buffers(struct pvfs2_bufmap *bufmap,
* Post and wait for the I/O upcall to finish
*/
static ssize_t wait_for_direct_io(enum PVFS_io_type type, struct inode *inode,
loff_t *offset, struct iovec *vec, unsigned long nr_segs,
loff_t *offset, struct iov_iter *iter,
size_t total_size, loff_t readahead_size)
{
struct pvfs2_inode_s *pvfs2_inode = PVFS2_I(inode);
@ -137,10 +137,9 @@ static ssize_t wait_for_direct_io(enum PVFS_io_type type, struct inode *inode,
new_op->upcall.req.io.offset = *offset;
gossip_debug(GOSSIP_FILE_DEBUG,
"%s(%pU): nr_segs %lu, offset: %llu total_size: %zd\n",
"%s(%pU): offset: %llu total_size: %zd\n",
__func__,
handle,
nr_segs,
llu(*offset),
total_size);
/*
@ -148,11 +147,9 @@ static ssize_t wait_for_direct_io(enum PVFS_io_type type, struct inode *inode,
* precopy_buffers only pertains to writes.
*/
if (type == PVFS_IO_WRITE) {
struct iov_iter iter;
iov_iter_init(&iter, WRITE, vec, nr_segs, total_size);
ret = precopy_buffers(bufmap,
buffer_index,
&iter,
iter,
total_size);
if (ret < 0)
goto out;
@ -213,11 +210,9 @@ static ssize_t wait_for_direct_io(enum PVFS_io_type type, struct inode *inode,
* postcopy_buffers only pertains to reads.
*/
if (type == PVFS_IO_READ) {
struct iov_iter iter;
iov_iter_init(&iter, READ, vec, nr_segs, new_op->downcall.resp.io.amt_complete);
ret = postcopy_buffers(bufmap,
buffer_index,
&iter,
iter,
new_op->downcall.resp.io.amt_complete);
if (ret < 0) {
/*
@ -563,6 +558,7 @@ static ssize_t do_readv_writev(enum PVFS_io_type type, struct file *file,
#endif
seg = 0;
while (total_count < count) {
struct iov_iter iter;
size_t each_count;
size_t amt_complete;
@ -583,8 +579,11 @@ static ssize_t do_readv_writev(enum PVFS_io_type type, struct file *file,
handle,
(int)*offset);
ret = wait_for_direct_io(type, inode, offset, ptr,
seg_array[seg], each_count, 0);
iov_iter_init(&iter, type == PVFS_IO_READ ? READ : WRITE,
ptr, seg_array[seg], each_count);
ret = wait_for_direct_io(type, inode, offset, &iter,
each_count, 0);
gossip_debug(GOSSIP_FILE_DEBUG,
"%s(%pU): return from wait_for_io:%d\n",
__func__,
@ -654,6 +653,7 @@ ssize_t pvfs2_inode_read(struct inode *inode,
struct pvfs2_inode_s *pvfs2_inode = PVFS2_I(inode);
size_t bufmap_size;
struct iovec vec;
struct iov_iter iter;
ssize_t ret = -EINVAL;
g_pvfs2_stats.reads++;
@ -676,7 +676,8 @@ ssize_t pvfs2_inode_read(struct inode *inode,
count,
llu(*offset));
ret = wait_for_direct_io(PVFS_IO_READ, inode, offset, &vec, 1,
iov_iter_init(&iter, READ, &vec, 1, count);
ret = wait_for_direct_io(PVFS_IO_READ, inode, offset, &iter,
count, readahead_size);
if (ret > 0)
*offset += ret;