From fe067853b0945a2ae18004e0a58023694e0779b9 Mon Sep 17 00:00:00 2001 From: joerg jungermann Date: Thu, 25 Sep 2014 22:05:12 -0700 Subject: [PATCH] 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 Signed-off-by: Jaegeuk Kim Signed-off-by: Gustavo Zacarias --- lib/libf2fs.c | 16 ++++++++++++++-- 1 file 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 -- 2.0.4