On 12/6/21 7:34 PM, Christoph Hellwig wrote:
On Fri, Dec 03, 2021 at 04:12:18PM +0530, Amit Daniel Kachhap wrote:
+ return read_from_oldmem_to_kernel(buf, count, ppos,
+ cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT));
Overly long line.
+ssize_t read_from_oldmem(char __user *ubuf, char *kbuf, size_t count,
+ u64 *ppos, bool encrypted)
{
unsigned long pfn, offset;
size_t nr_bytes;
@@ -156,19 +163,27 @@ ssize_t read_from_oldmem(char *buf, size_t count,
/* If pfn is not ram, return zeros for sparse dump files */
if (!pfn_is_ram(pfn)) {
tmp = 0;
- if (!userbuf)
- memset(buf, 0, nr_bytes);
- else if (clear_user(buf, nr_bytes))
+ if (kbuf)
+ memset(kbuf, 0, nr_bytes);
+ else if (clear_user(ubuf, nr_bytes))
tmp = -EFAULT;
This looks like a huge mess. What speak against using an iov_iter
here?
iov_iter seems to be a reasonable way. As a start I thought of adding
minimal changes.
