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author | joerg jungermann <jj@borkum.net> | 2014-09-25 22:05:12 -0700 |
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committer | JP Abgrall <jpa@google.com> | 2014-11-07 15:32:18 -0800 |
commit | 290d040e855230dbc21c35ccec7ee76fa6696567 (patch) | |
tree | 4cd050dffcb9b32013c1bd1c455b659690154554 /lib | |
parent | 7b74ed3d7cc84c3bb7e85b825cf17540baa3bbfa (diff) | |
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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>
Diffstat (limited to 'lib')
-rw-r--r-- | lib/libf2fs.c | 16 |
1 files changed, 14 insertions, 2 deletions
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 @@ int f2fs_get_device_info(struct f2fs_configuration *c) { 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 @@ int f2fs_get_device_info(struct f2fs_configuration *c) } } - 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 |