On Mon, 1 Mar 2021, gregkh@xxxxxxxxxxxxxxxxxxx wrote:
>
> The patch below does not apply to the 4.19-stable tree.
> If someone wants it applied there, or to any other stable or longterm
> tree, then please email the backport, including the original git commit
> id to <stable@xxxxxxxxxxxxxxx>.
>
> thanks,
>
> greg k-h
Hi
This is backport of the patch 054bee16163df023e2589db09fd27d81f7ad9e72 for
the stable branches 4.19 and 5.4.
Mikulas
commit 054bee16163df023e2589db09fd27d81f7ad9e72
Author: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Date: Thu Feb 4 05:20:52 2021 -0500
dm writecache: return the exact table values that were set
LVM doesn't like it when the target returns different values from what
was set in the constructor. Fix dm-writecache so that the returned
table values are exactly the same as requested values.
Signed-off-by: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx # v4.18+
Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
---
drivers/md/dm-writecache.c | 32 ++++++++++++++++----------------
1 file changed, 16 insertions(+), 16 deletions(-)
Index: linux-stable/drivers/md/dm-writecache.c
===================================================================
--- linux-stable.orig/drivers/md/dm-writecache.c 2021-07-18 20:54:39.000000000 +0200
+++ linux-stable/drivers/md/dm-writecache.c 2021-07-18 20:59:05.000000000 +0200
@@ -154,6 +154,7 @@ struct dm_writecache {
bool overwrote_committed:1;
bool memory_vmapped:1;
+ bool start_sector_set:1;
bool high_wm_percent_set:1;
bool low_wm_percent_set:1;
bool max_writeback_jobs_set:1;
@@ -162,6 +163,10 @@ struct dm_writecache {
bool writeback_fua_set:1;
bool flush_on_suspend:1;
+ unsigned high_wm_percent_value;
+ unsigned low_wm_percent_value;
+ unsigned autocommit_time_value;
+
unsigned writeback_all;
struct workqueue_struct *writeback_wq;
struct work_struct writeback_work;
@@ -2069,6 +2074,7 @@ static int writecache_ctr(struct dm_targ
if (sscanf(string, "%llu%c", &start_sector, &dummy) != 1)
goto invalid_optional;
wc->start_sector = start_sector;
+ wc->start_sector_set = true;
if (wc->start_sector != start_sector ||
wc->start_sector >= wc->memory_map_size >> SECTOR_SHIFT)
goto invalid_optional;
@@ -2078,6 +2084,7 @@ static int writecache_ctr(struct dm_targ
goto invalid_optional;
if (high_wm_percent < 0 || high_wm_percent > 100)
goto invalid_optional;
+ wc->high_wm_percent_value = high_wm_percent;
wc->high_wm_percent_set = true;
} else if (!strcasecmp(string, "low_watermark") && opt_params >= 1) {
string = dm_shift_arg(&as), opt_params--;
@@ -2085,6 +2092,7 @@ static int writecache_ctr(struct dm_targ
goto invalid_optional;
if (low_wm_percent < 0 || low_wm_percent > 100)
goto invalid_optional;
+ wc->low_wm_percent_value = low_wm_percent;
wc->low_wm_percent_set = true;
} else if (!strcasecmp(string, "writeback_jobs") && opt_params >= 1) {
string = dm_shift_arg(&as), opt_params--;
@@ -2104,6 +2112,7 @@ static int writecache_ctr(struct dm_targ
if (autocommit_msecs > 3600000)
goto invalid_optional;
wc->autocommit_jiffies = msecs_to_jiffies(autocommit_msecs);
+ wc->autocommit_time_value = autocommit_msecs;
wc->autocommit_time_set = true;
} else if (!strcasecmp(string, "fua")) {
if (WC_MODE_PMEM(wc)) {
@@ -2305,7 +2314,6 @@ static void writecache_status(struct dm_
struct dm_writecache *wc = ti->private;
unsigned extra_args;
unsigned sz = 0;
- uint64_t x;
switch (type) {
case STATUSTYPE_INFO:
@@ -2317,7 +2325,7 @@ static void writecache_status(struct dm_
DMEMIT("%c %s %s %u ", WC_MODE_PMEM(wc) ? 'p' : 's',
wc->dev->name, wc->ssd_dev->name, wc->block_size);
extra_args = 0;
- if (wc->start_sector)
+ if (wc->start_sector_set)
extra_args += 2;
if (wc->high_wm_percent_set)
extra_args += 2;
@@ -2333,26 +2341,18 @@ static void writecache_status(struct dm_
extra_args++;
DMEMIT("%u", extra_args);
- if (wc->start_sector)
+ if (wc->start_sector_set)
DMEMIT(" start_sector %llu", (unsigned long long)wc->start_sector);
- if (wc->high_wm_percent_set) {
- x = (uint64_t)wc->freelist_high_watermark * 100;
- x += wc->n_blocks / 2;
- do_div(x, (size_t)wc->n_blocks);
- DMEMIT(" high_watermark %u", 100 - (unsigned)x);
- }
- if (wc->low_wm_percent_set) {
- x = (uint64_t)wc->freelist_low_watermark * 100;
- x += wc->n_blocks / 2;
- do_div(x, (size_t)wc->n_blocks);
- DMEMIT(" low_watermark %u", 100 - (unsigned)x);
- }
+ if (wc->high_wm_percent_set)
+ DMEMIT(" high_watermark %u", wc->high_wm_percent_value);
+ if (wc->low_wm_percent_set)
+ DMEMIT(" low_watermark %u", wc->low_wm_percent_value);
if (wc->max_writeback_jobs_set)
DMEMIT(" writeback_jobs %u", wc->max_writeback_jobs);
if (wc->autocommit_blocks_set)
DMEMIT(" autocommit_blocks %u", wc->autocommit_blocks);
if (wc->autocommit_time_set)
- DMEMIT(" autocommit_time %u", jiffies_to_msecs(wc->autocommit_jiffies));
+ DMEMIT(" autocommit_time %u", wc->autocommit_time_value);
if (wc->writeback_fua_set)
DMEMIT(" %sfua", wc->writeback_fua ? "" : "no");
break;
