afs: Don't invoke the server to read data beyond EOF

When writing a new page, clear space in the page rather than attempting to
load it from the server if the space is beyond the EOF.

Signed-off-by: David Howells <dhowells@redhat.com>
This commit is contained in:
David Howells 2018-10-20 00:57:57 +01:00
parent f51375cd9e
commit 2a0b4f64c9

View File

@ -33,10 +33,21 @@ static int afs_fill_page(struct afs_vnode *vnode, struct key *key,
loff_t pos, unsigned int len, struct page *page)
{
struct afs_read *req;
size_t p;
void *data;
int ret;
_enter(",,%llu", (unsigned long long)pos);
if (pos >= vnode->vfs_inode.i_size) {
p = pos & ~PAGE_MASK;
ASSERTCMP(p + len, <=, PAGE_SIZE);
data = kmap(page);
memset(data + p, 0, len);
kunmap(page);
return 0;
}
req = kzalloc(sizeof(struct afs_read) + sizeof(struct page *),
GFP_KERNEL);
if (!req)