From f1b5618e013af28b3c78daf424436a79674423c0 Mon Sep 17 00:00:00 2001 From: David Howells Date: Thu, 1 Nov 2018 23:36:32 +0000 Subject: vfs: Add a sample program for the new mount API Add a sample program to demonstrate fsopen/fsmount/move_mount to mount something. To make it compile on all arches, irrespective of whether or not syscall numbers are assigned, define the syscall number to -1 if it isn't to cause the kernel to return -ENOSYS. Signed-off-by: David Howells Signed-off-by: Al Viro --- samples/Kconfig | 9 +- samples/Makefile | 2 +- samples/statx/Makefile | 7 -- samples/statx/test-statx.c | 258 ------------------------------------------- samples/vfs/Makefile | 10 ++ samples/vfs/test-fsmount.c | 133 ++++++++++++++++++++++ samples/vfs/test-statx.c | 267 +++++++++++++++++++++++++++++++++++++++++++++ 7 files changed, 416 insertions(+), 270 deletions(-) delete mode 100644 samples/statx/Makefile delete mode 100644 samples/statx/test-statx.c create mode 100644 samples/vfs/Makefile create mode 100644 samples/vfs/test-fsmount.c create mode 100644 samples/vfs/test-statx.c diff --git a/samples/Kconfig b/samples/Kconfig index d19754ccad08..30a89425009c 100644 --- a/samples/Kconfig +++ b/samples/Kconfig @@ -154,10 +154,11 @@ config SAMPLE_ANDROID_BINDERFS Builds a sample program to illustrate the use of the Android binderfs filesystem. -config SAMPLE_STATX - bool "Build example extended-stat using code" - depends on BROKEN +config SAMPLE_VFS + bool "Build example programs that use new VFS system calls" help - Build example userspace program to use the new extended-stat syscall. + Build example userspace programs that use new VFS system calls such + as mount API and statx(). Note that this is restricted to the x86 + arch whilst it accesses system calls that aren't yet in all arches. endif # SAMPLES diff --git a/samples/Makefile b/samples/Makefile index b1142a958811..95d71ffd62d5 100644 --- a/samples/Makefile +++ b/samples/Makefile @@ -3,4 +3,4 @@ obj-$(CONFIG_SAMPLES) += kobject/ kprobes/ trace_events/ livepatch/ \ hw_breakpoint/ kfifo/ kdb/ hidraw/ rpmsg/ seccomp/ \ configfs/ connector/ v4l/ trace_printk/ \ - vfio-mdev/ statx/ qmi/ binderfs/ + vfio-mdev/ vfs/ qmi/ binderfs/ diff --git a/samples/statx/Makefile b/samples/statx/Makefile deleted file mode 100644 index 59df7c25a9d1..000000000000 --- a/samples/statx/Makefile +++ /dev/null @@ -1,7 +0,0 @@ -# List of programs to build -hostprogs-$(CONFIG_SAMPLE_STATX) := test-statx - -# Tell kbuild to always build the programs -always := $(hostprogs-y) - -HOSTCFLAGS_test-statx.o += -I$(objtree)/usr/include diff --git a/samples/statx/test-statx.c b/samples/statx/test-statx.c deleted file mode 100644 index d4d77b09412c..000000000000 --- a/samples/statx/test-statx.c +++ /dev/null @@ -1,258 +0,0 @@ -/* Test the statx() system call. - * - * Note that the output of this program is intended to look like the output of - * /bin/stat where possible. - * - * Copyright (C) 2015 Red Hat, Inc. All Rights Reserved. - * Written by David Howells (dhowells@redhat.com) - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public Licence - * as published by the Free Software Foundation; either version - * 2 of the Licence, or (at your option) any later version. - */ - -#define _GNU_SOURCE -#define _ATFILE_SOURCE -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#define AT_STATX_SYNC_TYPE 0x6000 -#define AT_STATX_SYNC_AS_STAT 0x0000 -#define AT_STATX_FORCE_SYNC 0x2000 -#define AT_STATX_DONT_SYNC 0x4000 - -static __attribute__((unused)) -ssize_t statx(int dfd, const char *filename, unsigned flags, - unsigned int mask, struct statx *buffer) -{ - return syscall(__NR_statx, dfd, filename, flags, mask, buffer); -} - -static void print_time(const char *field, struct statx_timestamp *ts) -{ - struct tm tm; - time_t tim; - char buffer[100]; - int len; - - tim = ts->tv_sec; - if (!localtime_r(&tim, &tm)) { - perror("localtime_r"); - exit(1); - } - len = strftime(buffer, 100, "%F %T", &tm); - if (len == 0) { - perror("strftime"); - exit(1); - } - printf("%s", field); - fwrite(buffer, 1, len, stdout); - printf(".%09u", ts->tv_nsec); - len = strftime(buffer, 100, "%z", &tm); - if (len == 0) { - perror("strftime2"); - exit(1); - } - fwrite(buffer, 1, len, stdout); - printf("\n"); -} - -static void dump_statx(struct statx *stx) -{ - char buffer[256], ft = '?'; - - printf("results=%x\n", stx->stx_mask); - - printf(" "); - if (stx->stx_mask & STATX_SIZE) - printf(" Size: %-15llu", (unsigned long long)stx->stx_size); - if (stx->stx_mask & STATX_BLOCKS) - printf(" Blocks: %-10llu", (unsigned long long)stx->stx_blocks); - printf(" IO Block: %-6llu", (unsigned long long)stx->stx_blksize); - if (stx->stx_mask & STATX_TYPE) { - switch (stx->stx_mode & S_IFMT) { - case S_IFIFO: printf(" FIFO\n"); ft = 'p'; break; - case S_IFCHR: printf(" character special file\n"); ft = 'c'; break; - case S_IFDIR: printf(" directory\n"); ft = 'd'; break; - case S_IFBLK: printf(" block special file\n"); ft = 'b'; break; - case S_IFREG: printf(" regular file\n"); ft = '-'; break; - case S_IFLNK: printf(" symbolic link\n"); ft = 'l'; break; - case S_IFSOCK: printf(" socket\n"); ft = 's'; break; - default: - printf(" unknown type (%o)\n", stx->stx_mode & S_IFMT); - break; - } - } else { - printf(" no type\n"); - } - - sprintf(buffer, "%02x:%02x", stx->stx_dev_major, stx->stx_dev_minor); - printf("Device: %-15s", buffer); - if (stx->stx_mask & STATX_INO) - printf(" Inode: %-11llu", (unsigned long long) stx->stx_ino); - if (stx->stx_mask & STATX_NLINK) - printf(" Links: %-5u", stx->stx_nlink); - if (stx->stx_mask & STATX_TYPE) { - switch (stx->stx_mode & S_IFMT) { - case S_IFBLK: - case S_IFCHR: - printf(" Device type: %u,%u", - stx->stx_rdev_major, stx->stx_rdev_minor); - break; - } - } - printf("\n"); - - if (stx->stx_mask & STATX_MODE) - printf("Access: (%04o/%c%c%c%c%c%c%c%c%c%c) ", - stx->stx_mode & 07777, - ft, - stx->stx_mode & S_IRUSR ? 'r' : '-', - stx->stx_mode & S_IWUSR ? 'w' : '-', - stx->stx_mode & S_IXUSR ? 'x' : '-', - stx->stx_mode & S_IRGRP ? 'r' : '-', - stx->stx_mode & S_IWGRP ? 'w' : '-', - stx->stx_mode & S_IXGRP ? 'x' : '-', - stx->stx_mode & S_IROTH ? 'r' : '-', - stx->stx_mode & S_IWOTH ? 'w' : '-', - stx->stx_mode & S_IXOTH ? 'x' : '-'); - if (stx->stx_mask & STATX_UID) - printf("Uid: %5d ", stx->stx_uid); - if (stx->stx_mask & STATX_GID) - printf("Gid: %5d\n", stx->stx_gid); - - if (stx->stx_mask & STATX_ATIME) - print_time("Access: ", &stx->stx_atime); - if (stx->stx_mask & STATX_MTIME) - print_time("Modify: ", &stx->stx_mtime); - if (stx->stx_mask & STATX_CTIME) - print_time("Change: ", &stx->stx_ctime); - if (stx->stx_mask & STATX_BTIME) - print_time(" Birth: ", &stx->stx_btime); - - if (stx->stx_attributes_mask) { - unsigned char bits, mbits; - int loop, byte; - - static char attr_representation[64 + 1] = - /* STATX_ATTR_ flags: */ - "????????" /* 63-56 */ - "????????" /* 55-48 */ - "????????" /* 47-40 */ - "????????" /* 39-32 */ - "????????" /* 31-24 0x00000000-ff000000 */ - "????????" /* 23-16 0x00000000-00ff0000 */ - "???me???" /* 15- 8 0x00000000-0000ff00 */ - "?dai?c??" /* 7- 0 0x00000000-000000ff */ - ; - - printf("Attributes: %016llx (", stx->stx_attributes); - for (byte = 64 - 8; byte >= 0; byte -= 8) { - bits = stx->stx_attributes >> byte; - mbits = stx->stx_attributes_mask >> byte; - for (loop = 7; loop >= 0; loop--) { - int bit = byte + loop; - - if (!(mbits & 0x80)) - putchar('.'); /* Not supported */ - else if (bits & 0x80) - putchar(attr_representation[63 - bit]); - else - putchar('-'); /* Not set */ - bits <<= 1; - mbits <<= 1; - } - if (byte) - putchar(' '); - } - printf(")\n"); - } -} - -static void dump_hex(unsigned long long *data, int from, int to) -{ - unsigned offset, print_offset = 1, col = 0; - - from /= 8; - to = (to + 7) / 8; - - for (offset = from; offset < to; offset++) { - if (print_offset) { - printf("%04x: ", offset * 8); - print_offset = 0; - } - printf("%016llx", data[offset]); - col++; - if ((col & 3) == 0) { - printf("\n"); - print_offset = 1; - } else { - printf(" "); - } - } - - if (!print_offset) - printf("\n"); -} - -int main(int argc, char **argv) -{ - struct statx stx; - int ret, raw = 0, atflag = AT_SYMLINK_NOFOLLOW; - - unsigned int mask = STATX_ALL; - - for (argv++; *argv; argv++) { - if (strcmp(*argv, "-F") == 0) { - atflag &= ~AT_STATX_SYNC_TYPE; - atflag |= AT_STATX_FORCE_SYNC; - continue; - } - if (strcmp(*argv, "-D") == 0) { - atflag &= ~AT_STATX_SYNC_TYPE; - atflag |= AT_STATX_DONT_SYNC; - continue; - } - if (strcmp(*argv, "-L") == 0) { - atflag &= ~AT_SYMLINK_NOFOLLOW; - continue; - } - if (strcmp(*argv, "-O") == 0) { - mask &= ~STATX_BASIC_STATS; - continue; - } - if (strcmp(*argv, "-A") == 0) { - atflag |= AT_NO_AUTOMOUNT; - continue; - } - if (strcmp(*argv, "-R") == 0) { - raw = 1; - continue; - } - - memset(&stx, 0xbf, sizeof(stx)); - ret = statx(AT_FDCWD, *argv, atflag, mask, &stx); - printf("statx(%s) = %d\n", *argv, ret); - if (ret < 0) { - perror(*argv); - exit(1); - } - - if (raw) - dump_hex((unsigned long long *)&stx, 0, sizeof(stx)); - - dump_statx(&stx); - } - return 0; -} diff --git a/samples/vfs/Makefile b/samples/vfs/Makefile new file mode 100644 index 000000000000..4ac9690fb3c4 --- /dev/null +++ b/samples/vfs/Makefile @@ -0,0 +1,10 @@ +# List of programs to build +hostprogs-$(CONFIG_SAMPLE_VFS) := \ + test-fsmount \ + test-statx + +# Tell kbuild to always build the programs +always := $(hostprogs-y) + +HOSTCFLAGS_test-fsmount.o += -I$(objtree)/usr/include +HOSTCFLAGS_test-statx.o += -I$(objtree)/usr/include diff --git a/samples/vfs/test-fsmount.c b/samples/vfs/test-fsmount.c new file mode 100644 index 000000000000..266d72b3dce4 --- /dev/null +++ b/samples/vfs/test-fsmount.c @@ -0,0 +1,133 @@ +/* fd-based mount test. + * + * Copyright (C) 2017 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define E(x) do { if ((x) == -1) { perror(#x); exit(1); } } while(0) + +static void check_messages(int fd) +{ + char buf[4096]; + int err, n; + + err = errno; + + for (;;) { + n = read(fd, buf, sizeof(buf)); + if (n < 0) + break; + n -= 2; + + switch (buf[0]) { + case 'e': + fprintf(stderr, "Error: %*.*s\n", n, n, buf + 2); + break; + case 'w': + fprintf(stderr, "Warning: %*.*s\n", n, n, buf + 2); + break; + case 'i': + fprintf(stderr, "Info: %*.*s\n", n, n, buf + 2); + break; + } + } + + errno = err; +} + +static __attribute__((noreturn)) +void mount_error(int fd, const char *s) +{ + check_messages(fd); + fprintf(stderr, "%s: %m\n", s); + exit(1); +} + +/* Hope -1 isn't a syscall */ +#ifndef __NR_fsopen +#define __NR_fsopen -1 +#endif +#ifndef __NR_fsmount +#define __NR_fsmount -1 +#endif +#ifndef __NR_fsconfig +#define __NR_fsconfig -1 +#endif +#ifndef __NR_move_mount +#define __NR_move_mount -1 +#endif + + +static inline int fsopen(const char *fs_name, unsigned int flags) +{ + return syscall(__NR_fsopen, fs_name, flags); +} + +static inline int fsmount(int fsfd, unsigned int flags, unsigned int ms_flags) +{ + return syscall(__NR_fsmount, fsfd, flags, ms_flags); +} + +static inline int fsconfig(int fsfd, unsigned int cmd, + const char *key, const void *val, int aux) +{ + return syscall(__NR_fsconfig, fsfd, cmd, key, val, aux); +} + +static inline int move_mount(int from_dfd, const char *from_pathname, + int to_dfd, const char *to_pathname, + unsigned int flags) +{ + return syscall(__NR_move_mount, + from_dfd, from_pathname, + to_dfd, to_pathname, flags); +} + +#define E_fsconfig(fd, cmd, key, val, aux) \ + do { \ + if (fsconfig(fd, cmd, key, val, aux) == -1) \ + mount_error(fd, key ?: "create"); \ + } while (0) + +int main(int argc, char *argv[]) +{ + int fsfd, mfd; + + /* Mount a publically available AFS filesystem */ + fsfd = fsopen("afs", 0); + if (fsfd == -1) { + perror("fsopen"); + exit(1); + } + + E_fsconfig(fsfd, FSCONFIG_SET_STRING, "source", "#grand.central.org:root.cell.", 0); + E_fsconfig(fsfd, FSCONFIG_CMD_CREATE, NULL, NULL, 0); + + mfd = fsmount(fsfd, 0, MOUNT_ATTR_RDONLY); + if (mfd < 0) + mount_error(fsfd, "fsmount"); + E(close(fsfd)); + + if (move_mount(mfd, "", AT_FDCWD, "/mnt", MOVE_MOUNT_F_EMPTY_PATH) < 0) { + perror("move_mount"); + exit(1); + } + + E(close(mfd)); + exit(0); +} diff --git a/samples/vfs/test-statx.c b/samples/vfs/test-statx.c new file mode 100644 index 000000000000..e91f918e84c4 --- /dev/null +++ b/samples/vfs/test-statx.c @@ -0,0 +1,267 @@ +/* Test the statx() system call. + * + * Note that the output of this program is intended to look like the output of + * /bin/stat where possible. + * + * Copyright (C) 2015 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ + +#define _GNU_SOURCE +#define _ATFILE_SOURCE +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#define statx foo +#define statx_timestamp foo_timestamp +#include +#undef statx +#undef statx_timestamp + +#define AT_STATX_SYNC_TYPE 0x6000 +#define AT_STATX_SYNC_AS_STAT 0x0000 +#define AT_STATX_FORCE_SYNC 0x2000 +#define AT_STATX_DONT_SYNC 0x4000 + +#ifndef __NR_statx +#define __NR_statx -1 +#endif + +static __attribute__((unused)) +ssize_t statx(int dfd, const char *filename, unsigned flags, + unsigned int mask, struct statx *buffer) +{ + return syscall(__NR_statx, dfd, filename, flags, mask, buffer); +} + +static void print_time(const char *field, struct statx_timestamp *ts) +{ + struct tm tm; + time_t tim; + char buffer[100]; + int len; + + tim = ts->tv_sec; + if (!localtime_r(&tim, &tm)) { + perror("localtime_r"); + exit(1); + } + len = strftime(buffer, 100, "%F %T", &tm); + if (len == 0) { + perror("strftime"); + exit(1); + } + printf("%s", field); + fwrite(buffer, 1, len, stdout); + printf(".%09u", ts->tv_nsec); + len = strftime(buffer, 100, "%z", &tm); + if (len == 0) { + perror("strftime2"); + exit(1); + } + fwrite(buffer, 1, len, stdout); + printf("\n"); +} + +static void dump_statx(struct statx *stx) +{ + char buffer[256], ft = '?'; + + printf("results=%x\n", stx->stx_mask); + + printf(" "); + if (stx->stx_mask & STATX_SIZE) + printf(" Size: %-15llu", (unsigned long long)stx->stx_size); + if (stx->stx_mask & STATX_BLOCKS) + printf(" Blocks: %-10llu", (unsigned long long)stx->stx_blocks); + printf(" IO Block: %-6llu", (unsigned long long)stx->stx_blksize); + if (stx->stx_mask & STATX_TYPE) { + switch (stx->stx_mode & S_IFMT) { + case S_IFIFO: printf(" FIFO\n"); ft = 'p'; break; + case S_IFCHR: printf(" character special file\n"); ft = 'c'; break; + case S_IFDIR: printf(" directory\n"); ft = 'd'; break; + case S_IFBLK: printf(" block special file\n"); ft = 'b'; break; + case S_IFREG: printf(" regular file\n"); ft = '-'; break; + case S_IFLNK: printf(" symbolic link\n"); ft = 'l'; break; + case S_IFSOCK: printf(" socket\n"); ft = 's'; break; + default: + printf(" unknown type (%o)\n", stx->stx_mode & S_IFMT); + break; + } + } else { + printf(" no type\n"); + } + + sprintf(buffer, "%02x:%02x", stx->stx_dev_major, stx->stx_dev_minor); + printf("Device: %-15s", buffer); + if (stx->stx_mask & STATX_INO) + printf(" Inode: %-11llu", (unsigned long long) stx->stx_ino); + if (stx->stx_mask & STATX_NLINK) + printf(" Links: %-5u", stx->stx_nlink); + if (stx->stx_mask & STATX_TYPE) { + switch (stx->stx_mode & S_IFMT) { + case S_IFBLK: + case S_IFCHR: + printf(" Device type: %u,%u", + stx->stx_rdev_major, stx->stx_rdev_minor); + break; + } + } + printf("\n"); + + if (stx->stx_mask & STATX_MODE) + printf("Access: (%04o/%c%c%c%c%c%c%c%c%c%c) ", + stx->stx_mode & 07777, + ft, + stx->stx_mode & S_IRUSR ? 'r' : '-', + stx->stx_mode & S_IWUSR ? 'w' : '-', + stx->stx_mode & S_IXUSR ? 'x' : '-', + stx->stx_mode & S_IRGRP ? 'r' : '-', + stx->stx_mode & S_IWGRP ? 'w' : '-', + stx->stx_mode & S_IXGRP ? 'x' : '-', + stx->stx_mode & S_IROTH ? 'r' : '-', + stx->stx_mode & S_IWOTH ? 'w' : '-', + stx->stx_mode & S_IXOTH ? 'x' : '-'); + if (stx->stx_mask & STATX_UID) + printf("Uid: %5d ", stx->stx_uid); + if (stx->stx_mask & STATX_GID) + printf("Gid: %5d\n", stx->stx_gid); + + if (stx->stx_mask & STATX_ATIME) + print_time("Access: ", &stx->stx_atime); + if (stx->stx_mask & STATX_MTIME) + print_time("Modify: ", &stx->stx_mtime); + if (stx->stx_mask & STATX_CTIME) + print_time("Change: ", &stx->stx_ctime); + if (stx->stx_mask & STATX_BTIME) + print_time(" Birth: ", &stx->stx_btime); + + if (stx->stx_attributes_mask) { + unsigned char bits, mbits; + int loop, byte; + + static char attr_representation[64 + 1] = + /* STATX_ATTR_ flags: */ + "????????" /* 63-56 */ + "????????" /* 55-48 */ + "????????" /* 47-40 */ + "????????" /* 39-32 */ + "????????" /* 31-24 0x00000000-ff000000 */ + "????????" /* 23-16 0x00000000-00ff0000 */ + "???me???" /* 15- 8 0x00000000-0000ff00 */ + "?dai?c??" /* 7- 0 0x00000000-000000ff */ + ; + + printf("Attributes: %016llx (", + (unsigned long long)stx->stx_attributes); + for (byte = 64 - 8; byte >= 0; byte -= 8) { + bits = stx->stx_attributes >> byte; + mbits = stx->stx_attributes_mask >> byte; + for (loop = 7; loop >= 0; loop--) { + int bit = byte + loop; + + if (!(mbits & 0x80)) + putchar('.'); /* Not supported */ + else if (bits & 0x80) + putchar(attr_representation[63 - bit]); + else + putchar('-'); /* Not set */ + bits <<= 1; + mbits <<= 1; + } + if (byte) + putchar(' '); + } + printf(")\n"); + } +} + +static void dump_hex(unsigned long long *data, int from, int to) +{ + unsigned offset, print_offset = 1, col = 0; + + from /= 8; + to = (to + 7) / 8; + + for (offset = from; offset < to; offset++) { + if (print_offset) { + printf("%04x: ", offset * 8); + print_offset = 0; + } + printf("%016llx", data[offset]); + col++; + if ((col & 3) == 0) { + printf("\n"); + print_offset = 1; + } else { + printf(" "); + } + } + + if (!print_offset) + printf("\n"); +} + +int main(int argc, char **argv) +{ + struct statx stx; + int ret, raw = 0, atflag = AT_SYMLINK_NOFOLLOW; + + unsigned int mask = STATX_ALL; + + for (argv++; *argv; argv++) { + if (strcmp(*argv, "-F") == 0) { + atflag &= ~AT_STATX_SYNC_TYPE; + atflag |= AT_STATX_FORCE_SYNC; + continue; + } + if (strcmp(*argv, "-D") == 0) { + atflag &= ~AT_STATX_SYNC_TYPE; + atflag |= AT_STATX_DONT_SYNC; + continue; + } + if (strcmp(*argv, "-L") == 0) { + atflag &= ~AT_SYMLINK_NOFOLLOW; + continue; + } + if (strcmp(*argv, "-O") == 0) { + mask &= ~STATX_BASIC_STATS; + continue; + } + if (strcmp(*argv, "-A") == 0) { + atflag |= AT_NO_AUTOMOUNT; + continue; + } + if (strcmp(*argv, "-R") == 0) { + raw = 1; + continue; + } + + memset(&stx, 0xbf, sizeof(stx)); + ret = statx(AT_FDCWD, *argv, atflag, mask, &stx); + printf("statx(%s) = %d\n", *argv, ret); + if (ret < 0) { + perror(*argv); + exit(1); + } + + if (raw) + dump_hex((unsigned long long *)&stx, 0, sizeof(stx)); + + dump_statx(&stx); + } + return 0; +} -- cgit v1.2.3