Commit 7ce469a5 authored by Yan, Zheng's avatar Yan, Zheng Committed by Ilya Dryomov

ceph: fix splice read for no Fc capability case

When iov_iter type is ITER_PIPE, copy_page_to_iter() increases
the page's reference and add the page to a pipe_buffer. It also
set the pipe_buffer's ops to page_cache_pipe_buf_ops. The comfirm
callback in page_cache_pipe_buf_ops expects the page is from page
cache and uptodate, otherwise it return error.

For ceph_sync_read() case, pages are not from page cache. So we
can't call copy_page_to_iter() when iov_iter type is ITER_PIPE.
The fix is using iov_iter_get_pages_alloc() to allocate pages
for the pipe. (the code is similar to default_file_splice_read)
Signed-off-by: default avatarYan, Zheng <zyan@redhat.com>
parent 2b1ac852
......@@ -458,71 +458,60 @@ enum {
* only return a short read to the caller if we hit EOF.
*/
static int striped_read(struct inode *inode,
u64 off, u64 len,
u64 pos, u64 len,
struct page **pages, int num_pages,
int *checkeof)
int page_align, int *checkeof)
{
struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
struct ceph_inode_info *ci = ceph_inode(inode);
u64 pos, this_len, left;
u64 this_len;
loff_t i_size;
int page_align, pages_left;
int read, ret;
struct page **page_pos;
int page_idx;
int ret, read = 0;
bool hit_stripe, was_short;
/*
* we may need to do multiple reads. not atomic, unfortunately.
*/
pos = off;
left = len;
page_pos = pages;
pages_left = num_pages;
read = 0;
more:
page_align = pos & ~PAGE_MASK;
this_len = left;
this_len = len;
page_idx = (page_align + read) >> PAGE_SHIFT;
ret = ceph_osdc_readpages(&fsc->client->osdc, ceph_vino(inode),
&ci->i_layout, pos, &this_len,
ci->i_truncate_seq,
ci->i_truncate_size,
page_pos, pages_left, page_align);
ci->i_truncate_seq, ci->i_truncate_size,
pages + page_idx, num_pages - page_idx,
((page_align + read) & ~PAGE_MASK));
if (ret == -ENOENT)
ret = 0;
hit_stripe = this_len < left;
hit_stripe = this_len < len;
was_short = ret >= 0 && ret < this_len;
dout("striped_read %llu~%llu (read %u) got %d%s%s\n", pos, left, read,
dout("striped_read %llu~%llu (read %u) got %d%s%s\n", pos, len, read,
ret, hit_stripe ? " HITSTRIPE" : "", was_short ? " SHORT" : "");
i_size = i_size_read(inode);
if (ret >= 0) {
int didpages;
if (was_short && (pos + ret < i_size)) {
int zlen = min(this_len - ret, i_size - pos - ret);
int zoff = (off & ~PAGE_MASK) + read + ret;
int zoff = page_align + read + ret;
dout(" zero gap %llu to %llu\n",
pos + ret, pos + ret + zlen);
pos + ret, pos + ret + zlen);
ceph_zero_page_vector_range(zoff, zlen, pages);
ret += zlen;
}
didpages = (page_align + ret) >> PAGE_SHIFT;
read += ret;
pos += ret;
read = pos - off;
left -= ret;
page_pos += didpages;
pages_left -= didpages;
len -= ret;
/* hit stripe and need continue*/
if (left && hit_stripe && pos < i_size)
if (len && hit_stripe && pos < i_size)
goto more;
}
if (read > 0) {
ret = read;
/* did we bounce off eof? */
if (pos + left > i_size)
if (pos + len > i_size)
*checkeof = CHECK_EOF;
}
......@@ -536,15 +525,16 @@ static int striped_read(struct inode *inode,
*
* If the read spans object boundary, just do multiple reads.
*/
static ssize_t ceph_sync_read(struct kiocb *iocb, struct iov_iter *i,
int *checkeof)
static ssize_t ceph_sync_read(struct kiocb *iocb, struct iov_iter *to,
int *checkeof)
{
struct file *file = iocb->ki_filp;
struct inode *inode = file_inode(file);
struct page **pages;
u64 off = iocb->ki_pos;
int num_pages, ret;
size_t len = iov_iter_count(i);
int num_pages;
ssize_t ret;
size_t len = iov_iter_count(to);
dout("sync_read on file %p %llu~%u %s\n", file, off,
(unsigned)len,
......@@ -563,35 +553,56 @@ static ssize_t ceph_sync_read(struct kiocb *iocb, struct iov_iter *i,
if (ret < 0)
return ret;
num_pages = calc_pages_for(off, len);
pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL);
if (IS_ERR(pages))
return PTR_ERR(pages);
ret = striped_read(inode, off, len, pages,
num_pages, checkeof);
if (ret > 0) {
int l, k = 0;
size_t left = ret;
while (left) {
size_t page_off = off & ~PAGE_MASK;
size_t copy = min_t(size_t, left,
PAGE_SIZE - page_off);
l = copy_page_to_iter(pages[k++], page_off, copy, i);
off += l;
left -= l;
if (l < copy)
break;
if (unlikely(to->type & ITER_PIPE)) {
size_t page_off;
ret = iov_iter_get_pages_alloc(to, &pages, len,
&page_off);
if (ret <= 0)
return -ENOMEM;
num_pages = DIV_ROUND_UP(ret + page_off, PAGE_SIZE);
ret = striped_read(inode, off, ret, pages, num_pages,
page_off, checkeof);
if (ret > 0) {
iov_iter_advance(to, ret);
off += ret;
} else {
iov_iter_advance(to, 0);
}
ceph_put_page_vector(pages, num_pages, false);
} else {
num_pages = calc_pages_for(off, len);
pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL);
if (IS_ERR(pages))
return PTR_ERR(pages);
ret = striped_read(inode, off, len, pages, num_pages,
(off & ~PAGE_MASK), checkeof);
if (ret > 0) {
int l, k = 0;
size_t left = ret;
while (left) {
size_t page_off = off & ~PAGE_MASK;
size_t copy = min_t(size_t, left,
PAGE_SIZE - page_off);
l = copy_page_to_iter(pages[k++], page_off,
copy, to);
off += l;
left -= l;
if (l < copy)
break;
}
}
ceph_release_page_vector(pages, num_pages);
}
ceph_release_page_vector(pages, num_pages);
if (off > iocb->ki_pos) {
ret = off - iocb->ki_pos;
iocb->ki_pos = off;
}
dout("sync_read result %d\n", ret);
dout("sync_read result %zd\n", ret);
return ret;
}
......@@ -1771,6 +1782,7 @@ const struct file_operations ceph_file_fops = {
.fsync = ceph_fsync,
.lock = ceph_lock,
.flock = ceph_flock,
.splice_read = generic_file_splice_read,
.splice_write = iter_file_splice_write,
.unlocked_ioctl = ceph_ioctl,
.compat_ioctl = ceph_ioctl,
......
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