aboutsummaryrefslogtreecommitdiff
path: root/lib/bitmap.c
diff options
context:
space:
mode:
authorLinus Torvalds <[email protected]>2016-10-11 17:34:10 -0700
committerLinus Torvalds <[email protected]>2016-10-11 17:34:10 -0700
commita379f71a30dddbd2e7393624e455ce53c87965d1 (patch)
treec9c71b3eb19ff7e8618ff29e9d5ac99882b823e1 /lib/bitmap.c
parentde34f4da7f62ff59ac6e1ef320b0fcfa3296fce3 (diff)
parent9c5d760b8d229b94c5030863a5edaee5f1a9d7b7 (diff)
Merge branch 'akpm' (patches from Andrew)
Merge more updates from Andrew Morton: - a few block updates that fell in my lap - lib/ updates - checkpatch - autofs - ipc - a ton of misc other things * emailed patches from Andrew Morton <[email protected]>: (100 commits) mm: split gfp_mask and mapping flags into separate fields fs: use mapping_set_error instead of opencoded set_bit treewide: remove redundant #include <linux/kconfig.h> hung_task: allow hung_task_panic when hung_task_warnings is 0 kthread: add kerneldoc for kthread_create() kthread: better support freezable kthread workers kthread: allow to modify delayed kthread work kthread: allow to cancel kthread work kthread: initial support for delayed kthread work kthread: detect when a kthread work is used by more workers kthread: add kthread_destroy_worker() kthread: add kthread_create_worker*() kthread: allow to call __kthread_create_on_node() with va_list args kthread/smpboot: do not park in kthread_create_on_cpu() kthread: kthread worker API cleanup kthread: rename probe_kthread_data() to kthread_probe_data() scripts/tags.sh: enable code completion in VIM mm: kmemleak: avoid using __va() on addresses that don't have a lowmem mapping kdump, vmcoreinfo: report memory sections virtual addresses ipc/sem.c: add cond_resched in exit_sme ...
Diffstat (limited to 'lib/bitmap.c')
-rw-r--r--lib/bitmap.c50
1 files changed, 46 insertions, 4 deletions
diff --git a/lib/bitmap.c b/lib/bitmap.c
index eca88087fa8a..0b66f0e5eb6b 100644
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -496,6 +496,11 @@ EXPORT_SYMBOL(bitmap_print_to_pagebuf);
* ranges. Consecutively set bits are shown as two hyphen-separated
* decimal numbers, the smallest and largest bit numbers set in
* the range.
+ * Optionally each range can be postfixed to denote that only parts of it
+ * should be set. The range will divided to groups of specific size.
+ * From each group will be used only defined amount of bits.
+ * Syntax: range:used_size/group_size
+ * Example: 0-1023:2/256 ==> 0,1,256,257,512,513,768,769
*
* Returns 0 on success, -errno on invalid input strings.
* Error values:
@@ -507,16 +512,20 @@ static int __bitmap_parselist(const char *buf, unsigned int buflen,
int is_user, unsigned long *maskp,
int nmaskbits)
{
- unsigned a, b;
+ unsigned int a, b, old_a, old_b;
+ unsigned int group_size, used_size;
int c, old_c, totaldigits, ndigits;
const char __user __force *ubuf = (const char __user __force *)buf;
- int at_start, in_range;
+ int at_start, in_range, in_partial_range;
totaldigits = c = 0;
+ old_a = old_b = 0;
+ group_size = used_size = 0;
bitmap_zero(maskp, nmaskbits);
do {
at_start = 1;
in_range = 0;
+ in_partial_range = 0;
a = b = 0;
ndigits = totaldigits;
@@ -547,6 +556,24 @@ static int __bitmap_parselist(const char *buf, unsigned int buflen,
if ((totaldigits != ndigits) && isspace(old_c))
return -EINVAL;
+ if (c == '/') {
+ used_size = a;
+ at_start = 1;
+ in_range = 0;
+ a = b = 0;
+ continue;
+ }
+
+ if (c == ':') {
+ old_a = a;
+ old_b = b;
+ at_start = 1;
+ in_range = 0;
+ in_partial_range = 1;
+ a = b = 0;
+ continue;
+ }
+
if (c == '-') {
if (at_start || in_range)
return -EINVAL;
@@ -567,15 +594,30 @@ static int __bitmap_parselist(const char *buf, unsigned int buflen,
}
if (ndigits == totaldigits)
continue;
+ if (in_partial_range) {
+ group_size = a;
+ a = old_a;
+ b = old_b;
+ old_a = old_b = 0;
+ }
/* if no digit is after '-', it's wrong*/
if (at_start && in_range)
return -EINVAL;
- if (!(a <= b))
+ if (!(a <= b) || !(used_size <= group_size))
return -EINVAL;
if (b >= nmaskbits)
return -ERANGE;
while (a <= b) {
- set_bit(a, maskp);
+ if (in_partial_range) {
+ static int pos_in_group = 1;
+
+ if (pos_in_group <= used_size)
+ set_bit(a, maskp);
+
+ if (a == b || ++pos_in_group > group_size)
+ pos_in_group = 1;
+ } else
+ set_bit(a, maskp);
a++;
}
} while (buflen && c == ',');