16 Aug
2023
16 Aug
'23
11:17 a.m.
On Wed, Aug 16, 2023 at 03:38:10PM +0500, Muhammad Usama Anjum wrote:
The PAGEMAP_SCAN IOCTL on the pagemap file can be used to get or optionally clear the info about page table entries.
[...]
--- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c
[...]
+static long do_pagemap_scan(struct mm_struct *mm, unsigned long uarg) +{
[...]
- for (walk_start = p.arg.start; walk_start < p.arg.end;
walk_start = p.arg.walk_end) {
[...]
/* The walk_end isn't set when ret is zero */if (!p.arg.walk_end)p.arg.walk_end = p.arg.end;
This is now redundant with the `if` after the loop. [1]
if (ret != -ENOSPC)break;if (p.arg.vec_len == 0 || p.found_pages == p.arg.max_pages)break;- }
- /* ENOSPC signifies early stop (buffer full) from the walk. */
- if (!ret || ret == -ENOSPC)
ret = n_ranges_out;- if (!p.arg.walk_end)
p.arg.walk_end = p.arg.end;
[1] The one above.
Best Regards Michał Mirosław