ceph_aio_read(): keep iov_iter across retries

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2014-03-05 19:22:23 -05:00
parent 886a391150
commit 05bb2e0bc7

View file

@ -806,6 +806,9 @@ static ssize_t ceph_aio_read(struct kiocb *iocb, const struct iovec *iov,
ssize_t ret;
int want, got = 0;
int checkeof = 0, read = 0;
struct iov_iter i;
iov_iter_init(&i, iov, nr_segs, len, 0);
again:
dout("aio_read %p %llx.%llx %llu~%u trying to get caps on %p\n",
@ -822,28 +825,26 @@ static ssize_t ceph_aio_read(struct kiocb *iocb, const struct iovec *iov,
if ((got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0 ||
(iocb->ki_filp->f_flags & O_DIRECT) ||
(fi->flags & CEPH_F_SYNC)) {
struct iov_iter i;
dout("aio_sync_read %p %llx.%llx %llu~%u got cap refs on %s\n",
inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len,
ceph_cap_string(got));
if (!read)
len = iov_length(iov, nr_segs);
iov_iter_init(&i, iov, nr_segs, len, read);
/* hmm, this isn't really async... */
ret = ceph_sync_read(iocb, &i, &checkeof);
} else {
/*
* We can't modify the content of iov,
* so we only read from beginning.
*
* When we switch generic_file_aio_read() to iov_iter, the
* if () below will be removed -- AV
*/
if (read) {
iocb->ki_pos = pos;
len = iocb->ki_nbytes;
read = 0;
iov_iter_init(&i, iov, nr_segs, len, 0);
}
dout("aio_read %p %llx.%llx %llu~%u got cap refs on %s\n",
inode, ceph_vinop(inode), pos, (unsigned)len,
@ -866,6 +867,7 @@ static ssize_t ceph_aio_read(struct kiocb *iocb, const struct iovec *iov,
", reading more\n", iocb->ki_pos,
inode->i_size);
iov_iter_advance(&i, ret);
read += ret;
len -= ret;
checkeof = 0;