From: Andries.Brouwer@cwi.nl Below a patch that changes struct stat for a number of architectures. Maintainers, please watch carefully. Struct stat is used to transfer information from kernel to user space on a stat() system call. It has fields st_dev, st_rdev. The size of these fields is in principle unrelated to the size of a dev_t in user space or the size of a dev_t or kdev_t in kernel space. It is just the "capacity" of the channel. The actual amount of useful information is the minimum of the four sizes (kernel dev_t, kernel kdev_t, user dev_t, width of stat st_dev, st_rdev fields). The goal of this patch is to make sure that the stat() and stat64() system calls transmit at least 32 and 64 bits, respectively. This is achieved by using the padding that was present already. We fail when no padding was present, or when the padding is on the wrong side (after the field, while the machine is big-endian). alpha: stat: uses unsigned int, 32 bits arm: stat: uses unsigned short - bad. The padding is on one side, which means that this can be made into unsigned long only on little endian systems. FIXED - unless __ARMEB__. stat64: used unsigned short - FIXED, now unsigned long long. cris: stat: used unsigned short - FIXED, now unsigned long stat64: used unsigned short - FIXED, now unsigned long long. i386: stat: used unsigned short - FIXED, now unsigned long stat64: used unsigned short - FIXED, now unsigned long long. ia64: stat: uses unsigned long, 64 bits m68k: stat: used unsigned short - bad, but this cannot be fixed since m68k is big-endian, and the available padding is on the wrong side. NOT FIXED. stat64: used unsigned short - FIXED, now unsigned long long. mips: stat: uses dev_t which is unsigned int, 32 bits stat64: used unsigned long, 32 bits. NOT FIXED. (There is padding on one side, so this can be fixed if __MIPSEL__.) mips64: stat: uses dev_t which is unsigned int, 32 bits parisc: stat: uses dev_t, 32 bits stat64: uses unsigned long long, 64 bits ppc: stat: uses dev_t which is unsigned int, 32 bits stat64: unsigned long long, 64 bits ppc64: stat: uses dev_t which is unsigned long, 64 bits stat64: uses unsigned long, 64 bits sparc: stat: uses unsigned short, no padding. NOT FIXED. stat64: used unsigned short - FIXED, now unsigned long long. sparc64:stat: uses dev_t which is unsigned int, 32 bits stat64: used unsigned short - FIXED, now unsigned long long. s390: stat: used unsigned short, big-endian, padding on the wrong side, NOT FIXED. stat64: used unsigned short - FIXED, now unsigned long long. s390x: stat: uses unsigned long, 64 bits sh: stat: used unsigned short, but padding maybe on wrong side. NOT FIXED. stat64: used unsigned short - FIXED, now unsigned long long. v850: stat: used __kernel_dev_t. BUG: NEVER use __kernel types in a user space interface. Replaced the types. FIXED - now unsigned int - 32 bits. stat64: FIXED - now unsigned long long - 64 bits. x86_64: stat: uses unsigned long, 64 bits So, on most architectures we achieve the aim of 32 bits for stat, 64 bits for stat64. On all architectures we achieve at least 16 bits for stat, 32 bits for stat64. Andries diff -u --recursive --new-file -X /linux/dontdiff a/include/asm-arm/stat.h b/include/asm-arm/stat.h include/asm-arm/stat.h | 26 +++++++++++--------------- include/asm-cris/stat.h | 16 +++++++--------- include/asm-i386/stat.h | 16 +++++++--------- include/asm-m68k/stat.h | 8 +++----- include/asm-s390/stat.h | 12 +++++------- include/asm-sh/stat.h | 18 ++---------------- include/asm-sparc/stat.h | 8 +++----- include/asm-sparc64/stat.h | 6 ++---- include/asm-v850/stat.h | 34 ++++++++++++++++------------------ 9 files changed, 56 insertions(+), 88 deletions(-) diff -puN include/asm-arm/stat.h~stat_t-larger-dev_t include/asm-arm/stat.h --- 25/include/asm-arm/stat.h~stat_t-larger-dev_t 2003-03-24 09:28:22.000000000 -0800 +++ 25-akpm/include/asm-arm/stat.h 2003-03-24 09:28:22.000000000 -0800 @@ -18,15 +18,23 @@ struct __old_kernel_stat { #define STAT_HAVE_NSEC struct stat { +#if defined(__ARMEB__) unsigned short st_dev; unsigned short __pad1; - unsigned long st_ino; +#else + unsigned long st_dev; +#endif + unsigned long st_ino; unsigned short st_mode; unsigned short st_nlink; unsigned short st_uid; unsigned short st_gid; +#if defined(__ARMEB__) unsigned short st_rdev; unsigned short __pad2; +#else + unsigned long st_rdev; +#endif unsigned long st_size; unsigned long st_blksize; unsigned long st_blocks; @@ -46,13 +54,7 @@ struct stat { * in the hope that the kernel has stretched to using larger sizes. */ struct stat64 { -#if defined(__ARMEB__) - unsigned char __pad0b[6]; - unsigned short st_dev; -#else - unsigned short st_dev; - unsigned char __pad0b[6]; -#endif + unsigned long long st_dev; unsigned char __pad0[4]; #define STAT64_HAS_BROKEN_ST_INO 1 @@ -63,13 +65,7 @@ struct stat64 { unsigned long st_uid; unsigned long st_gid; -#if defined(__ARMEB__) - unsigned char __pad3b[6]; - unsigned short st_rdev; -#else /* Must be little */ - unsigned short st_rdev; - unsigned char __pad3b[6]; -#endif + unsigned long long st_rdev; unsigned char __pad3[4]; long long st_size; diff -puN include/asm-cris/stat.h~stat_t-larger-dev_t include/asm-cris/stat.h --- 25/include/asm-cris/stat.h~stat_t-larger-dev_t 2003-03-24 09:28:22.000000000 -0800 +++ 25-akpm/include/asm-cris/stat.h 2003-03-24 09:28:22.000000000 -0800 @@ -21,15 +21,13 @@ struct __old_kernel_stat { #define STAT_HAVE_NSEC 1 struct stat { - unsigned short st_dev; - unsigned short __pad1; - unsigned long st_ino; + unsigned long st_dev; + unsigned long st_ino; unsigned short st_mode; unsigned short st_nlink; unsigned short st_uid; unsigned short st_gid; - unsigned short st_rdev; - unsigned short __pad2; + unsigned long st_rdev; unsigned long st_size; unsigned long st_blksize; unsigned long st_blocks; @@ -47,8 +45,8 @@ struct stat { * insane amounts of padding around dev_t's. */ struct stat64 { - unsigned short st_dev; - unsigned char __pad0[10]; + unsigned long long st_dev; + unsigned char __pad0[4]; #define STAT64_HAS_BROKEN_ST_INO 1 unsigned long __st_ino; @@ -59,8 +57,8 @@ struct stat64 { unsigned long st_uid; unsigned long st_gid; - unsigned short st_rdev; - unsigned char __pad3[10]; + unsigned long long st_rdev; + unsigned char __pad3[4]; long long st_size; unsigned long st_blksize; diff -puN include/asm-i386/stat.h~stat_t-larger-dev_t include/asm-i386/stat.h --- 25/include/asm-i386/stat.h~stat_t-larger-dev_t 2003-03-24 09:28:22.000000000 -0800 +++ 25-akpm/include/asm-i386/stat.h 2003-03-24 09:28:22.000000000 -0800 @@ -16,15 +16,13 @@ struct __old_kernel_stat { }; struct stat { - unsigned short st_dev; - unsigned short __pad1; - unsigned long st_ino; + unsigned long st_dev; + unsigned long st_ino; unsigned short st_mode; unsigned short st_nlink; unsigned short st_uid; unsigned short st_gid; - unsigned short st_rdev; - unsigned short __pad2; + unsigned long st_rdev; unsigned long st_size; unsigned long st_blksize; unsigned long st_blocks; @@ -42,8 +40,8 @@ struct stat { * insane amounts of padding around dev_t's. */ struct stat64 { - unsigned short st_dev; - unsigned char __pad0[10]; + unsigned long long st_dev; + unsigned char __pad0[4]; #define STAT64_HAS_BROKEN_ST_INO 1 unsigned long __st_ino; @@ -54,8 +52,8 @@ struct stat64 { unsigned long st_uid; unsigned long st_gid; - unsigned short st_rdev; - unsigned char __pad3[10]; + unsigned long long st_rdev; + unsigned char __pad3[4]; long long st_size; unsigned long st_blksize; diff -puN include/asm-m68k/stat.h~stat_t-larger-dev_t include/asm-m68k/stat.h --- 25/include/asm-m68k/stat.h~stat_t-larger-dev_t 2003-03-24 09:28:22.000000000 -0800 +++ 25-akpm/include/asm-m68k/stat.h 2003-03-24 09:28:22.000000000 -0800 @@ -18,7 +18,7 @@ struct __old_kernel_stat { struct stat { unsigned short st_dev; unsigned short __pad1; - unsigned long st_ino; + unsigned long st_ino; unsigned short st_mode; unsigned short st_nlink; unsigned short st_uid; @@ -42,8 +42,7 @@ struct stat { * insane amounts of padding around dev_t's. */ struct stat64 { - unsigned char __pad0[6]; - unsigned short st_dev; + unsigned long long st_dev; unsigned char __pad1[2]; #define STAT64_HAS_BROKEN_ST_INO 1 @@ -55,8 +54,7 @@ struct stat64 { unsigned long st_uid; unsigned long st_gid; - unsigned char __pad2[6]; - unsigned short st_rdev; + unsigned long long st_rdev; unsigned char __pad3[2]; long long st_size; diff -puN include/asm-s390/stat.h~stat_t-larger-dev_t include/asm-s390/stat.h --- 25/include/asm-s390/stat.h~stat_t-larger-dev_t 2003-03-24 09:28:22.000000000 -0800 +++ 25-akpm/include/asm-s390/stat.h 2003-03-24 09:28:22.000000000 -0800 @@ -26,7 +26,7 @@ struct __old_kernel_stat { struct stat { unsigned short st_dev; unsigned short __pad1; - unsigned long st_ino; + unsigned long st_ino; unsigned short st_mode; unsigned short st_nlink; unsigned short st_uid; @@ -52,8 +52,7 @@ struct stat { * insane amounts of padding around dev_t's. */ struct stat64 { - unsigned char __pad0[6]; - unsigned short st_dev; + unsigned long long st_dev; unsigned int __pad1; #define STAT64_HAS_BROKEN_ST_INO 1 unsigned long __st_ino; @@ -61,10 +60,9 @@ struct stat64 { unsigned int st_nlink; unsigned long st_uid; unsigned long st_gid; - unsigned char __pad2[6]; - unsigned short st_rdev; + unsigned long long st_rdev; unsigned int __pad3; - long long st_size; + long long st_size; unsigned long st_blksize; unsigned char __pad4[4]; unsigned long __pad5; /* future possible st_blocks high bits */ @@ -75,7 +73,7 @@ struct stat64 { unsigned long st_mtime_nsec; unsigned long st_ctime; unsigned long st_ctime_nsec; /* will be high 32 bits of ctime someday */ - unsigned long long st_ino; + unsigned long long st_ino; }; #endif diff -puN include/asm-sh/stat.h~stat_t-larger-dev_t include/asm-sh/stat.h --- 25/include/asm-sh/stat.h~stat_t-larger-dev_t 2003-03-24 09:28:22.000000000 -0800 +++ 25-akpm/include/asm-sh/stat.h 2003-03-24 09:28:22.000000000 -0800 @@ -44,15 +44,7 @@ struct stat { * insane amounts of padding around dev_t's. */ struct stat64 { -#if defined(__BIG_ENDIAN__) - unsigned char __pad0b[6]; - unsigned short st_dev; -#elif defined(__LITTLE_ENDIAN__) - unsigned short st_dev; - unsigned char __pad0b[6]; -#else -#error Must know endian to build stat64 structure! -#endif + unsigned long long st_dev; unsigned char __pad0[4]; unsigned long st_ino; @@ -62,13 +54,7 @@ struct stat64 { unsigned long st_uid; unsigned long st_gid; -#if defined(__BIG_ENDIAN__) - unsigned char __pad3b[6]; - unsigned short st_rdev; -#else /* Must be little */ - unsigned short st_rdev; - unsigned char __pad3b[6]; -#endif + unsigned long long st_rdev; unsigned char __pad3[4]; long long st_size; diff -puN include/asm-sparc64/stat.h~stat_t-larger-dev_t include/asm-sparc64/stat.h --- 25/include/asm-sparc64/stat.h~stat_t-larger-dev_t 2003-03-24 09:28:22.000000000 -0800 +++ 25-akpm/include/asm-sparc64/stat.h 2003-03-24 09:28:22.000000000 -0800 @@ -25,8 +25,7 @@ struct stat { /* This is sparc32 stat64 structure. */ struct stat64 { - unsigned char __pad0[6]; - unsigned short st_dev; + unsigned long long st_dev; unsigned long long st_ino; @@ -36,8 +35,7 @@ struct stat64 { unsigned int st_uid; unsigned int st_gid; - unsigned char __pad2[6]; - unsigned short st_rdev; + unsigned long long st_rdev; unsigned char __pad3[8]; diff -puN include/asm-sparc/stat.h~stat_t-larger-dev_t include/asm-sparc/stat.h --- 25/include/asm-sparc/stat.h~stat_t-larger-dev_t 2003-03-24 09:28:22.000000000 -0800 +++ 25-akpm/include/asm-sparc/stat.h 2003-03-24 09:28:22.000000000 -0800 @@ -41,10 +41,9 @@ struct stat { #define STAT_HAVE_NSEC 1 struct stat64 { - unsigned char __pad0[6]; - unsigned short st_dev; + unsigned long long st_dev; - unsigned long long st_ino; + unsigned long long st_ino; unsigned int st_mode; unsigned int st_nlink; @@ -52,8 +51,7 @@ struct stat64 { unsigned int st_uid; unsigned int st_gid; - unsigned char __pad2[6]; - unsigned short st_rdev; + unsigned long long st_rdev; unsigned char __pad3[8]; diff -puN include/asm-v850/stat.h~stat_t-larger-dev_t include/asm-v850/stat.h --- 25/include/asm-v850/stat.h~stat_t-larger-dev_t 2003-03-24 09:28:22.000000000 -0800 +++ 25-akpm/include/asm-v850/stat.h 2003-03-24 09:28:22.000000000 -0800 @@ -17,14 +17,14 @@ #include struct stat { - __kernel_dev_t st_dev; - __kernel_ino_t st_ino; - __kernel_mode_t st_mode; - __kernel_nlink_t st_nlink; - __kernel_uid_t st_uid; - __kernel_gid_t st_gid; - __kernel_dev_t st_rdev; - __kernel_off_t st_size; + unsigned int st_dev; + unsigned long st_ino; + unsigned int st_mode; + unsigned int st_nlink; + unsigned int st_uid; + unsigned int st_gid; + unsigned int st_rdev; + long st_size; unsigned long st_blksize; unsigned long st_blocks; unsigned long st_atime; @@ -38,23 +38,21 @@ struct stat { }; struct stat64 { - __kernel_dev_t st_dev; - unsigned long __unused0; + unsigned long long st_dev; unsigned long __unused1; - __kernel_ino64_t st_ino; + unsigned long long st_ino; - __kernel_mode_t st_mode; - __kernel_nlink_t st_nlink; + unsigned int st_mode; + unsigned int st_nlink; - __kernel_uid_t st_uid; - __kernel_gid_t st_gid; + unsigned int st_uid; + unsigned int st_gid; - __kernel_dev_t st_rdev; - unsigned long __unused2; + unsigned long long st_rdev; unsigned long __unused3; - __kernel_loff_t st_size; + long long st_size; unsigned long st_blksize; unsigned long st_blocks; /* No. of 512-byte blocks allocated */ _