[PATCH 003 of 13] md: Update status_resync to handle LARGE devices.

From: NeilBrown
Date: Thu Mar 16 2006 - 23:47:05 EST



status_resync - used by /proc/mdstat to report the status of a resync,
assumes that device sizes will always fit into an 'unsigned long' This
is no longer the case...

Signed-off-by: Neil Brown <neilb@xxxxxxx>

### Diffstat output
./drivers/md/md.c | 30 ++++++++++++++++++++++++------
1 file changed, 24 insertions(+), 6 deletions(-)

diff ./drivers/md/md.c~current~ ./drivers/md/md.c
--- ./drivers/md/md.c~current~ 2006-03-17 11:48:08.000000000 +1100
+++ ./drivers/md/md.c 2006-03-17 11:48:30.000000000 +1100
@@ -4040,7 +4040,10 @@ static void status_unused(struct seq_fil

static void status_resync(struct seq_file *seq, mddev_t * mddev)
{
- unsigned long max_blocks, resync, res, dt, db, rt;
+ sector_t max_blocks, resync, res;
+ unsigned long dt, db, rt;
+ int scale;
+ unsigned int per_milli;

resync = (mddev->curr_resync - atomic_read(&mddev->recovery_active))/2;

@@ -4056,9 +4059,22 @@ static void status_resync(struct seq_fil
MD_BUG();
return;
}
- res = (resync/1024)*1000/(max_blocks/1024 + 1);
+ /* Pick 'scale' such that (resync>>scale)*1000 will fit
+ * in a sector_t, and (max_blocks>>scale) will fit in a
+ * u32, as those are the requirements for sector_div.
+ * Thus 'scale' must be at least 10
+ */
+ scale = 10;
+ if (sizeof(sector_t) > sizeof(unsigned long)) {
+ while ( max_blocks/2 > (1ULL<<(scale+32)))
+ scale++;
+ }
+ res = (resync>>scale)*1000;
+ sector_div(res, (u32)((max_blocks>>scale)+1));
+
+ per_milli = res;
{
- int i, x = res/50, y = 20-x;
+ int i, x = per_milli/50, y = 20-x;
seq_printf(seq, "[");
for (i = 0; i < x; i++)
seq_printf(seq, "=");
@@ -4067,10 +4083,12 @@ static void status_resync(struct seq_fil
seq_printf(seq, ".");
seq_printf(seq, "] ");
}
- seq_printf(seq, " %s =%3lu.%lu%% (%lu/%lu)",
+ seq_printf(seq, " %s =%3u.%u%% (%llu/%llu)",
(test_bit(MD_RECOVERY_SYNC, &mddev->recovery) ?
"resync" : "recovery"),
- res/10, res % 10, resync, max_blocks);
+ per_milli/10, per_milli % 10,
+ (unsigned long long) resync,
+ (unsigned long long) max_blocks);

/*
* We do not want to overflow, so the order of operands and
@@ -4084,7 +4102,7 @@ static void status_resync(struct seq_fil
dt = ((jiffies - mddev->resync_mark) / HZ);
if (!dt) dt++;
db = resync - (mddev->resync_mark_cnt/2);
- rt = (dt * ((max_blocks-resync) / (db/100+1)))/100;
+ rt = (dt * ((unsigned long)(max_blocks-resync) / (db/100+1)))/100;

seq_printf(seq, " finish=%lu.%lumin", rt / 60, (rt % 60)/6);

-
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