[dm-devel] [PATCH v4 1/4] dm dust: report some message results back to user directly

[Mike Snitzer]

It is on the dm-devel patchwork list to pick up for the 5.9 merge
window.  I've just been busy with other work.

Thanks,
Mike

On Sat, Jun 27 2020 at  9:08pm -0400,
yangerkun <yangerkun at huawei.com> wrote:

> Hi Mike, does there any advice for this patchset?
> 
> Thanks,
> Kun.
> 
> 在 2020/6/20 5:10, Bryan Gurney 写道:
> >From: yangerkun <yangerkun at huawei.com>
> >
> >From: yangerkun <yangerkun at huawei.com>
> >
> >Some type of message(queryblock/countbadblocks/removebadblock) may better
> >report results to user directly. Do it with DMEMIT.
> >
> >[Bryan: maintain __func__ output in DMEMIT messages]
> >
> >Signed-off-by: yangerkun <yangerkun at huawei.com>
> >Signed-off-by: Bryan Gurney <bgurney at redhat.com>
> >---
> >  drivers/md/dm-dust.c | 31 ++++++++++++++++++-------------
> >  1 file changed, 18 insertions(+), 13 deletions(-)
> >
> >diff --git a/drivers/md/dm-dust.c b/drivers/md/dm-dust.c
> >index ff03b90072c5..f1f2dd6a4e84 100644
> >--- a/drivers/md/dm-dust.c
> >+++ b/drivers/md/dm-dust.c
> >@@ -138,20 +138,22 @@ static int dust_add_block(struct dust_device *dd, unsigned long long block,
> >  	return 0;
> >  }
> >-static int dust_query_block(struct dust_device *dd, unsigned long long block)
> >+static int dust_query_block(struct dust_device *dd, unsigned long long block, char *result,
> >+			    unsigned int maxlen, unsigned int *sz_ptr)
> >  {
> >  	struct badblock *bblock;
> >  	unsigned long flags;
> >+	unsigned int sz = *sz_ptr;
> >  	spin_lock_irqsave(&dd->dust_lock, flags);
> >  	bblock = dust_rb_search(&dd->badblocklist, block);
> >  	if (bblock != NULL)
> >-		DMINFO("%s: block %llu found in badblocklist", __func__, block);
> >+		DMEMIT("%s: block %llu found in badblocklist", __func__, block);
> >  	else
> >-		DMINFO("%s: block %llu not found in badblocklist", __func__, block);
> >+		DMEMIT("%s: block %llu not found in badblocklist", __func__, block);
> >  	spin_unlock_irqrestore(&dd->dust_lock, flags);
> >-	return 0;
> >+	return 1;
> >  }
> >  static int __dust_map_read(struct dust_device *dd, sector_t thisblock)
> >@@ -259,11 +261,13 @@ static bool __dust_clear_badblocks(struct rb_root *tree,
> >  	return true;
> >  }
> >-static int dust_clear_badblocks(struct dust_device *dd)
> >+static int dust_clear_badblocks(struct dust_device *dd, char *result, unsigned int maxlen,
> >+				unsigned int *sz_ptr)
> >  {
> >  	unsigned long flags;
> >  	struct rb_root badblocklist;
> >  	unsigned long long badblock_count;
> >+	unsigned int sz = *sz_ptr;
> >  	spin_lock_irqsave(&dd->dust_lock, flags);
> >  	badblocklist = dd->badblocklist;
> >@@ -273,11 +277,11 @@ static int dust_clear_badblocks(struct dust_device *dd)
> >  	spin_unlock_irqrestore(&dd->dust_lock, flags);
> >  	if (!__dust_clear_badblocks(&badblocklist, badblock_count))
> >-		DMINFO("%s: no badblocks found", __func__);
> >+		DMEMIT("%s: no badblocks found", __func__);
> >  	else
> >-		DMINFO("%s: badblocks cleared", __func__);
> >+		DMEMIT("%s: badblocks cleared", __func__);
> >-	return 0;
> >+	return 1;
> >  }
> >  /*
> >@@ -383,7 +387,7 @@ static void dust_dtr(struct dm_target *ti)
> >  }
> >  static int dust_message(struct dm_target *ti, unsigned int argc, char **argv,
> >-			char *result_buf, unsigned int maxlen)
> >+			char *result, unsigned int maxlen)
> >  {
> >  	struct dust_device *dd = ti->private;
> >  	sector_t size = i_size_read(dd->dev->bdev->bd_inode) >> SECTOR_SHIFT;
> >@@ -393,6 +397,7 @@ static int dust_message(struct dm_target *ti, unsigned int argc, char **argv,
> >  	unsigned char wr_fail_cnt;
> >  	unsigned int tmp_ui;
> >  	unsigned long flags;
> >+	unsigned int sz = 0;
> >  	char dummy;
> >  	if (argc == 1) {
> >@@ -410,12 +415,12 @@ static int dust_message(struct dm_target *ti, unsigned int argc, char **argv,
> >  			r = 0;
> >  		} else if (!strcasecmp(argv[0], "countbadblocks")) {
> >  			spin_lock_irqsave(&dd->dust_lock, flags);
> >-			DMINFO("countbadblocks: %llu badblock(s) found",
> >+			DMEMIT("countbadblocks: %llu badblock(s) found",
> >  			       dd->badblock_count);
> >  			spin_unlock_irqrestore(&dd->dust_lock, flags);
> >-			r = 0;
> >+			r = 1;
> >  		} else if (!strcasecmp(argv[0], "clearbadblocks")) {
> >-			r = dust_clear_badblocks(dd);
> >+			r = dust_clear_badblocks(dd, result, maxlen, &sz);
> >  		} else if (!strcasecmp(argv[0], "quiet")) {
> >  			if (!dd->quiet_mode)
> >  				dd->quiet_mode = true;
> >@@ -441,7 +446,7 @@ static int dust_message(struct dm_target *ti, unsigned int argc, char **argv,
> >  		else if (!strcasecmp(argv[0], "removebadblock"))
> >  			r = dust_remove_block(dd, block);
> >  		else if (!strcasecmp(argv[0], "queryblock"))
> >-			r = dust_query_block(dd, block);
> >+			r = dust_query_block(dd, block, result, maxlen, &sz);
> >  		else
> >  			invalid_msg = true;
> >
>