mkfs.f2fs: possible endianes bug in mkfs.f2fs roll-forward speed
I might found a bug in mkfs.f2fs. while experimenting with f2fs on my big
endian MIPS32 device (platform lantiq, 14.07-rc3, uclibc).
I ran into an issue that mkfs.f2fs, was not able to format block devices if I
did not specify the sector count manually.
I hunted it down to lib/libf2fs.c.
After I found that the detected sector count equals to the wanted sector count
shifted left (32+9) times.
I found two issues:
Firstly it uses ioctl BLKGETSIZE, which writes to an uint32_t the size of the
device.
As c->total_sectors is of type uint64_t, the value is written in to the first
4 bytes.
That explained the left shift of 32 bits.
Secondly BLKGETSIZE determines the size of the device in bytes (AFAIK, learned
by observation).
In the first branch of the if-block patched below, the c->total_sectors is
calculated by
c->total_sectors = stat_buf.st_size / c->sector_size;
The else branch omits the devision. sector_sice is mostly 512, that explained
the left shift by 9 bytes.
* fixes sector count calculation
* uses BLKGETSIZE64 if avail
Signed-off-by: joerg jungermann <jj@borkum.net>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/lib/libf2fs.c b/lib/libf2fs.c
index 01ef4e9..73c551b 100644
--- a/lib/libf2fs.c
+++ b/lib/libf2fs.c
@@ -422,6 +422,9 @@
{
int32_t fd = 0;
uint32_t sector_size;
+#ifndef BLKGETSIZE64
+ uint32_t total_sectors;
+#endif
struct stat stat_buf;
struct hd_geometry geom;
u_int64_t wanted_total_sectors = c->total_sectors;
@@ -454,11 +457,20 @@
}
}
- if (ioctl(fd, BLKGETSIZE, &c->total_sectors) < 0) {
+#ifdef BLKGETSIZE64
+ if (ioctl(fd, BLKGETSIZE64, &c->total_sectors) < 0) {
MSG(0, "\tError: Cannot get the device size\n");
return -1;
}
-
+ c->total_sectors /= c->sector_size;
+#else
+ if (ioctl(fd, BLKGETSIZE, &total_sectors) < 0) {
+ MSG(0, "\tError: Cannot get the device size\n");
+ return -1;
+ }
+ total_sectors /= c->sector_size;
+ c->total_sectors = total_sectors;
+#endif
if (ioctl(fd, HDIO_GETGEO, &geom) < 0)
c->start_sector = 0;
else
