From 331f0800f1a3ddf6b365c65a37d0bfc5114b0c02 Mon Sep 17 00:00:00 2001 From: Yann Dirson Date: Tue, 18 May 2021 10:59:04 +0200 Subject: [PATCH] mkimage: allow -l to work on block devices on Linux When "mkimage -l" was run on a block device it would fail with erroneous message, because fstat reports a size of zero for those: mkimage: Bad size: "/dev/sdb4" is not valid image This patch identifies the "is a block device" case and reports it as such, and if it knows how to determine the size of a block device on the current OS, proceeds. As shown in http://www.mit.edu/afs.new/sipb/user/tytso/e2fsprogs/lib/blkid/getsize.c this is no portable task, and I only handled the case of a modern Linux kernel, which is what I can test. Signed-off-by: Yann Dirson --- tools/mkimage.c | 30 +++++++++++++++++++++++++++--- 1 file changed, 27 insertions(+), 3 deletions(-) diff --git a/tools/mkimage.c b/tools/mkimage.c index cc7b242faf..302bfcf971 100644 --- a/tools/mkimage.c +++ b/tools/mkimage.c @@ -12,6 +12,9 @@ #include "imximage.h" #include #include +#ifdef __linux__ +#include +#endif static void copy_file(int, const char *, int); @@ -402,6 +405,7 @@ int main(int argc, char **argv) } if (params.lflag || params.fflag) { + uint64_t size; /* * list header information of existing image */ @@ -412,14 +416,34 @@ int main(int argc, char **argv) exit (EXIT_FAILURE); } - if ((unsigned)sbuf.st_size < tparams->header_size) { + if ((sbuf.st_mode & S_IFMT) == S_IFBLK) { +#ifdef __linux__ +#if defined(__linux__) && defined(_IOR) && !defined(BLKGETSIZE64) +#define BLKGETSIZE64 _IOR(0x12,114,size_t) /* return device size in bytes (u64 *arg) */ +#endif + if (ioctl(ifd, BLKGETSIZE64, &size) < 0) { + fprintf (stderr, + "%s: failed to get size of block device \"%s\"\n", + params.cmdname, params.imagefile); + exit (EXIT_FAILURE); + } +#else fprintf (stderr, - "%s: Bad size: \"%s\" is not valid image\n", + "%s: \"%s\" is block device, don't know how to get its size\n", params.cmdname, params.imagefile); exit (EXIT_FAILURE); +#endif + } else if ((unsigned)sbuf.st_size < tparams->header_size) { + fprintf (stderr, + "%s: Bad size: \"%s\" is not valid image: size %ld < %u\n", + params.cmdname, params.imagefile, + sbuf.st_size, tparams->header_size); + exit (EXIT_FAILURE); + } else { + size = sbuf.st_size; } - ptr = mmap(0, sbuf.st_size, PROT_READ, MAP_SHARED, ifd, 0); + ptr = mmap(0, size, PROT_READ, MAP_SHARED, ifd, 0); if (ptr == MAP_FAILED) { fprintf (stderr, "%s: Can't read %s: %s\n", params.cmdname, params.imagefile, -- 2.39.5