[RFC v8 19/20] um: lkl: add block device support of UML
Hajime Tazaki
thehajime at gmail.com
Tue Jan 19 21:27:24 EST 2021
This commit adds block device support for library mode, and also added
several host utilities to run a simple test program
(tools/um/test/disk.c) successfully.
Signed-off-by: Hajime Tazaki <thehajime at gmail.com>
---
arch/um/Kconfig | 4 +
arch/um/include/asm/xor.h | 3 +-
arch/um/include/shared/as-layout.h | 1 +
arch/um/kernel/um_arch.c | 5 +
arch/um/lkl/include/uapi/asm/host_ops.h | 5 +
arch/um/lkl/include/uapi/asm/unistd.h | 2 +
arch/um/lkl/um/setup.c | 12 +
tools/testing/selftests/um/Makefile | 5 +-
tools/testing/selftests/um/cla.c | 159 ++++++++
tools/testing/selftests/um/cla.h | 33 ++
tools/testing/selftests/um/disk-ext4.sh | 6 +
tools/testing/selftests/um/disk-vfat.sh | 6 +
tools/testing/selftests/um/disk.c | 166 +++++++++
tools/testing/selftests/um/disk.sh | 67 ++++
tools/um/include/lkl.h | 206 +++++++++++
tools/um/include/lkl_host.h | 1 +
tools/um/lib/Build | 1 +
tools/um/lib/fs.c | 461 ++++++++++++++++++++++++
tools/um/lib/posix-host.c | 1 +
tools/um/lib/utils.c | 2 +
20 files changed, 1144 insertions(+), 2 deletions(-)
create mode 100644 tools/testing/selftests/um/cla.c
create mode 100644 tools/testing/selftests/um/cla.h
create mode 100755 tools/testing/selftests/um/disk-ext4.sh
create mode 100755 tools/testing/selftests/um/disk-vfat.sh
create mode 100644 tools/testing/selftests/um/disk.c
create mode 100755 tools/testing/selftests/um/disk.sh
create mode 100644 tools/um/lib/fs.c
diff --git a/arch/um/Kconfig b/arch/um/Kconfig
index 24c6596260de..5fb6a852d058 100644
--- a/arch/um/Kconfig
+++ b/arch/um/Kconfig
@@ -29,6 +29,10 @@ config UMMODE_LIB
select UACCESS_MEMCPY
select ARCH_THREAD_STACK_ALLOCATOR
select ARCH_HAS_SYSCALL_WRAPPER
+ select VFAT_FS
+ select NLS_CODEPAGE_437
+ select NLS_ISO8859_1
+ select BTRFS_FS
help
This mode switches a mode to build a library of UML (Linux
Kernel Library/LKL). If this is Y, the build only generates,
diff --git a/arch/um/include/asm/xor.h b/arch/um/include/asm/xor.h
index 36b33d62a35d..934a576ec4b2 100644
--- a/arch/um/include/asm/xor.h
+++ b/arch/um/include/asm/xor.h
@@ -4,4 +4,5 @@
/* pick an arbitrary one - measuring isn't possible with inf-cpu */
#define XOR_SELECT_TEMPLATE(x) \
- (time_travel_mode == TT_MODE_INFCPU ? &xor_block_8regs : NULL)
+ (time_travel_mode == TT_MODE_INFCPU || \
+ (IS_ENABLED(CONFIG_UMMODE_LIB)) ? &xor_block_8regs : NULL)
diff --git a/arch/um/include/shared/as-layout.h b/arch/um/include/shared/as-layout.h
index 5f286ef2721b..4423437a5ace 100644
--- a/arch/um/include/shared/as-layout.h
+++ b/arch/um/include/shared/as-layout.h
@@ -57,6 +57,7 @@ extern unsigned long host_task_size;
extern int linux_main(int argc, char **argv);
extern void uml_finishsetup(void);
+extern void uml_set_args(char *args);
struct siginfo;
extern void (*sig_info[])(int, struct siginfo *si, struct uml_pt_regs *);
diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c
index dfc6194b5ac7..3968842346a2 100644
--- a/arch/um/kernel/um_arch.c
+++ b/arch/um/kernel/um_arch.c
@@ -42,6 +42,11 @@ static void __init add_arg(char *arg)
strcat(command_line, arg);
}
+void __init uml_set_args(char *args)
+{
+ strcat(command_line, args);
+}
+
/*
* These fields are initialized at boot time and not changed.
* XXX This structure is used only in the non-SMP case. Maybe this
diff --git a/arch/um/lkl/include/uapi/asm/host_ops.h b/arch/um/lkl/include/uapi/asm/host_ops.h
index 85d7d4790602..c7239df7f807 100644
--- a/arch/um/lkl/include/uapi/asm/host_ops.h
+++ b/arch/um/lkl/include/uapi/asm/host_ops.h
@@ -12,11 +12,16 @@ struct lkl_jmp_buf {
/**
* struct lkl_host_operations - host operations used by the Linux kernel
*
+ * @um_devices: string containg the list of UML devices in command line
+ * format. This string is appended to the kernel command line and
+ * is provided here for convenience to be implemented by the host library.
+ *
* These operations must be provided by a host library or by the application
* itself.
*
*/
struct lkl_host_operations {
+ const char *um_devices;
};
/**
diff --git a/arch/um/lkl/include/uapi/asm/unistd.h b/arch/um/lkl/include/uapi/asm/unistd.h
index 6f5d67b45fbd..d777e4b597d2 100644
--- a/arch/um/lkl/include/uapi/asm/unistd.h
+++ b/arch/um/lkl/include/uapi/asm/unistd.h
@@ -3,6 +3,8 @@
#define __UM_LIBMODE_UAPI_UNISTD_H
#define __ARCH_WANT_NEW_STAT
+#define __ARCH_WANT_SET_GET_RLIMIT
+
#include <asm/bitsperlong.h>
#if __BITS_PER_LONG == 64
diff --git a/arch/um/lkl/um/setup.c b/arch/um/lkl/um/setup.c
index 12b235826573..f33e9f477b7a 100644
--- a/arch/um/lkl/um/setup.c
+++ b/arch/um/lkl/um/setup.c
@@ -45,13 +45,25 @@ static void __init *lkl_run_kernel(void *arg)
return NULL;
}
+static char _cmd_line[COMMAND_LINE_SIZE];
int __init lkl_start_kernel(struct lkl_host_operations *ops,
const char *fmt, ...)
{
+ va_list ap;
int ret;
lkl_ops = ops;
+ va_start(ap, fmt);
+ ret = vsnprintf(_cmd_line, COMMAND_LINE_SIZE, fmt, ap);
+ va_end(ap);
+
+ if (ops->um_devices)
+ strscpy(_cmd_line + ret, ops->um_devices,
+ COMMAND_LINE_SIZE - ret);
+
+ uml_set_args(_cmd_line);
+
init_sem = lkl_sem_alloc(0);
if (!init_sem)
return -ENOMEM;
diff --git a/tools/testing/selftests/um/Makefile b/tools/testing/selftests/um/Makefile
index 1b915f4bb751..df9561a0b3b4 100644
--- a/tools/testing/selftests/um/Makefile
+++ b/tools/testing/selftests/um/Makefile
@@ -4,10 +4,13 @@ top_srcdir = ../../../../
top_objdir = $(OUTPUT)/../../
CFLAGS := -fPIC -I$(top_objdir)/tools/um/include/ -I$(top_srcdir)/tools/um/include/ -g
-CFLAGS += test.c
+CFLAGS += test.c cla.c
LDFLAGS := -pie
LDLIBS := -L$(top_objdir)/tools/um -L$(top_srcdir)/tools/um -llinux -lpthread -lrt -lutil
TEST_GEN_PROGS := boot
+TEST_PROGS := disk-ext4.sh disk-vfat.sh
+TEST_PROGS_EXTENDED := test.sh disk.sh
+TEST_GEN_FILES := disk
include ../lib.mk
diff --git a/tools/testing/selftests/um/cla.c b/tools/testing/selftests/um/cla.c
new file mode 100644
index 000000000000..694e3a3822be
--- /dev/null
+++ b/tools/testing/selftests/um/cla.c
@@ -0,0 +1,159 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <stdlib.h>
+#ifdef __MINGW32__
+#include <winsock2.h>
+#else
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#endif
+
+#include "cla.h"
+
+static int cl_arg_parse_bool(struct cl_arg *arg, const char *value)
+{
+ *((int *)arg->store) = 1;
+ return 0;
+}
+
+static int cl_arg_parse_str(struct cl_arg *arg, const char *value)
+{
+ *((const char **)arg->store) = value;
+ return 0;
+}
+
+static int cl_arg_parse_int(struct cl_arg *arg, const char *value)
+{
+ errno = 0;
+ *((int *)arg->store) = strtol(value, NULL, 0);
+ return errno == 0;
+}
+
+static int cl_arg_parse_str_set(struct cl_arg *arg, const char *value)
+{
+ const char **set = arg->set;
+ int i;
+
+ for (i = 0; set[i] != NULL; i++) {
+ if (strcmp(set[i], value) == 0) {
+ *((int *)arg->store) = i;
+ return 0;
+ }
+ }
+
+ return (-1);
+}
+
+static int cl_arg_parse_ipv4(struct cl_arg *arg, const char *value)
+{
+ unsigned int addr;
+
+ if (!value)
+ return (-1);
+
+ addr = inet_addr(value);
+ if (addr == INADDR_NONE)
+ return (-1);
+ *((unsigned int *)arg->store) = addr;
+ return 0;
+}
+
+static cl_arg_parser_t parsers[] = {
+ [CL_ARG_BOOL] = cl_arg_parse_bool,
+ [CL_ARG_INT] = cl_arg_parse_int,
+ [CL_ARG_STR] = cl_arg_parse_str,
+ [CL_ARG_STR_SET] = cl_arg_parse_str_set,
+ [CL_ARG_IPV4] = cl_arg_parse_ipv4,
+};
+
+static struct cl_arg *find_short_arg(char name, struct cl_arg *args)
+{
+ struct cl_arg *arg;
+
+ for (arg = args; arg->short_name != 0; arg++) {
+ if (arg->short_name == name)
+ return arg;
+ }
+
+ return NULL;
+}
+
+static struct cl_arg *find_long_arg(const char *name, struct cl_arg *args)
+{
+ struct cl_arg *arg;
+
+ for (arg = args; arg->long_name; arg++) {
+ if (strcmp(arg->long_name, name) == 0)
+ return arg;
+ }
+
+ return NULL;
+}
+
+static void print_help(struct cl_arg *args)
+{
+ struct cl_arg *arg;
+
+ fprintf(stderr, "usage:\n");
+ for (arg = args; arg->long_name; arg++) {
+ fprintf(stderr, "-%c, --%-20s %s", arg->short_name,
+ arg->long_name, arg->help);
+ if (arg->type == CL_ARG_STR_SET) {
+ const char **set = arg->set;
+
+ fprintf(stderr, " [ ");
+ while (*set != NULL)
+ fprintf(stderr, "%s ", *(set++));
+ fprintf(stderr, "]");
+ }
+ fprintf(stderr, "\n");
+ }
+}
+
+int cla_parse_args(int argc, const char **argv, struct cl_arg *args)
+{
+ int i;
+
+ for (i = 1; i < argc; i++) {
+ struct cl_arg *arg = NULL;
+ cl_arg_parser_t parser;
+
+ if (argv[i][0] == '-') {
+ if (argv[i][1] != '-')
+ arg = find_short_arg(argv[i][1], args);
+ else
+ arg = find_long_arg(&argv[i][2], args);
+ }
+
+ if (!arg) {
+ fprintf(stderr, "unknown option '%s'\n", argv[i]);
+ print_help(args);
+ return (-1);
+ }
+
+ if (arg->type == CL_ARG_USER || arg->type >= CL_ARG_END)
+ parser = arg->parser;
+ else
+ parser = parsers[arg->type];
+
+ if (!parser) {
+ fprintf(stderr, "can't parse --'%s'/-'%c'\n",
+ arg->long_name, args->short_name);
+ return (-1);
+ }
+
+ if (parser(arg, argv[i + 1]) < 0) {
+ fprintf(stderr, "can't parse '%s'\n", argv[i]);
+ print_help(args);
+ return (-1);
+ }
+
+ if (arg->has_arg)
+ i++;
+ }
+
+ return 0;
+}
diff --git a/tools/testing/selftests/um/cla.h b/tools/testing/selftests/um/cla.h
new file mode 100644
index 000000000000..3d879233681f
--- /dev/null
+++ b/tools/testing/selftests/um/cla.h
@@ -0,0 +1,33 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef _LKL_TEST_CLA_H
+#define _LKL_TEST_CLA_H
+
+enum cl_arg_type {
+ CL_ARG_USER = 0,
+ CL_ARG_BOOL,
+ CL_ARG_INT,
+ CL_ARG_STR,
+ CL_ARG_STR_SET,
+ CL_ARG_IPV4,
+ CL_ARG_END,
+};
+
+struct cl_arg;
+
+typedef int (*cl_arg_parser_t)(struct cl_arg *arg, const char *value);
+
+struct cl_arg {
+ const char *long_name;
+ char short_name;
+ const char *help;
+ int has_arg;
+ enum cl_arg_type type;
+ void *store;
+ void *set;
+ cl_arg_parser_t parser;
+};
+
+int cla_parse_args(int argc, const char **argv, struct cl_arg *args);
+
+
+#endif /* _LKL_TEST_CLA_H */
diff --git a/tools/testing/selftests/um/disk-ext4.sh b/tools/testing/selftests/um/disk-ext4.sh
new file mode 100755
index 000000000000..a021f0efd057
--- /dev/null
+++ b/tools/testing/selftests/um/disk-ext4.sh
@@ -0,0 +1,6 @@
+#!/usr/bin/env bash
+# SPDX-License-Identifier: GPL-2.0
+
+script_dir=$(cd $(dirname ${BASH_SOURCE:-$0}); pwd)
+
+${script_dir}/disk.sh -t ext4
diff --git a/tools/testing/selftests/um/disk-vfat.sh b/tools/testing/selftests/um/disk-vfat.sh
new file mode 100755
index 000000000000..955ccec40193
--- /dev/null
+++ b/tools/testing/selftests/um/disk-vfat.sh
@@ -0,0 +1,6 @@
+#!/usr/bin/env bash
+# SPDX-License-Identifier: GPL-2.0
+
+script_dir=$(cd $(dirname ${BASH_SOURCE:-$0}); pwd)
+
+${script_dir}/disk.sh -t vfat
diff --git a/tools/testing/selftests/um/disk.c b/tools/testing/selftests/um/disk.c
new file mode 100644
index 000000000000..d70468e66170
--- /dev/null
+++ b/tools/testing/selftests/um/disk.c
@@ -0,0 +1,166 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <stdio.h>
+#include <unistd.h>
+#include <string.h>
+#include <time.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <lkl.h>
+#include <lkl_host.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+
+#include "test.h"
+#include "cla.h"
+
+static struct {
+ int printk;
+ const char *disk;
+ const char *fstype;
+ int partition;
+} cla;
+
+struct cl_arg args[] = {
+ {"disk", 'd', "disk file to use", 1, CL_ARG_STR, &cla.disk},
+ {"partition", 'P', "partition to mount", 1, CL_ARG_INT, &cla.partition},
+ {"type", 't', "filesystem type", 1, CL_ARG_STR, &cla.fstype},
+ {0},
+};
+
+
+static struct lkl_disk disk;
+static int disk_id = -1;
+
+int lkl_test_disk_add(void)
+{
+ disk.fd = open(cla.disk, O_RDWR);
+ if (disk.fd < 0)
+ goto out_unlink;
+
+ disk.ops = NULL;
+ disk.dev = (char *)cla.disk;
+
+ disk_id = lkl_disk_add(&disk);
+ if (disk_id < 0)
+ goto out_close;
+
+ goto out;
+
+out_close:
+ close(disk.fd);
+
+out_unlink:
+ unlink(cla.disk);
+
+out:
+ lkl_test_logf("disk fd/handle %x disk_id %d", disk.fd, disk_id);
+
+ if (disk_id >= 0)
+ return TEST_SUCCESS;
+
+ return TEST_FAILURE;
+}
+
+int lkl_test_disk_remove(void)
+{
+ int ret;
+
+ ret = lkl_disk_remove(disk);
+
+ close(disk.fd);
+
+ if (ret == 0)
+ return TEST_SUCCESS;
+
+ return TEST_FAILURE;
+}
+
+
+static char mnt_point[32];
+
+LKL_TEST_CALL(mount_dev, lkl_mount_dev, 0, disk_id, cla.partition, cla.fstype,
+ 0, NULL, mnt_point, sizeof(mnt_point))
+
+static int lkl_test_umount_dev(void)
+{
+ long ret, ret2;
+
+ ret = lkl_sys_chdir("/");
+
+ ret2 = lkl_umount_dev(disk_id, cla.partition, 0, 1000);
+
+ lkl_test_logf("%ld %ld", ret, ret2);
+
+ if (!ret && !ret2)
+ return TEST_SUCCESS;
+
+ return TEST_FAILURE;
+}
+
+struct lkl_dir *dir;
+
+static int lkl_test_opendir(void)
+{
+ int err;
+
+ dir = lkl_opendir(mnt_point, &err);
+
+ lkl_test_logf("lkl_opendir(%s) = %d %s\n", mnt_point, err,
+ lkl_strerror(err));
+
+ if (err == 0)
+ return TEST_SUCCESS;
+
+ return TEST_FAILURE;
+}
+
+static int lkl_test_readdir(void)
+{
+ struct lkl_linux_dirent64 *de = lkl_readdir(dir);
+ int wr = 0;
+
+ while (de) {
+ wr += lkl_test_logf("%s ", de->d_name);
+ if (wr >= 70) {
+ lkl_test_logf("\n");
+ wr = 0;
+ break;
+ }
+ de = lkl_readdir(dir);
+ }
+
+ if (lkl_errdir(dir) == 0)
+ return TEST_SUCCESS;
+
+ return TEST_FAILURE;
+}
+
+LKL_TEST_CALL(closedir, lkl_closedir, 0, dir);
+LKL_TEST_CALL(chdir_mnt_point, lkl_sys_chdir, 0, mnt_point);
+LKL_TEST_CALL(start_kernel, lkl_start_kernel, 0, &lkl_host_ops,
+ "mem=16M loglevel=8");
+LKL_TEST_CALL(stop_kernel, lkl_sys_halt, 0);
+
+struct lkl_test tests[] = {
+ LKL_TEST(disk_add),
+ LKL_TEST(start_kernel),
+ LKL_TEST(mount_dev),
+ LKL_TEST(chdir_mnt_point),
+ LKL_TEST(opendir),
+ LKL_TEST(readdir),
+ LKL_TEST(closedir),
+ LKL_TEST(umount_dev),
+ LKL_TEST(stop_kernel),
+ LKL_TEST(disk_remove),
+
+};
+
+int main(int argc, const char **argv)
+{
+ if (cla_parse_args(argc, argv, args) < 0)
+ return (-1);
+
+ return lkl_test_run(tests, sizeof(tests)/sizeof(struct lkl_test),
+ "disk %s", cla.fstype);
+}
diff --git a/tools/testing/selftests/um/disk.sh b/tools/testing/selftests/um/disk.sh
new file mode 100755
index 000000000000..9cf67a76bbe3
--- /dev/null
+++ b/tools/testing/selftests/um/disk.sh
@@ -0,0 +1,67 @@
+#!/usr/bin/env bash
+# SPDX-License-Identifier: GPL-2.0
+
+script_dir=$(cd $(dirname ${BASH_SOURCE:-$0}); pwd)
+
+source $script_dir/test.sh
+
+function prepfs()
+{
+ set -e
+
+ file=`mktemp`
+
+ dd if=/dev/zero of=$file bs=1024 count=204800
+
+ yes | mkfs.$1 $file
+
+ if ! [ -z $ANDROID_WDIR ]; then
+ adb shell mkdir -p $ANDROID_WDIR
+ adb push $file $ANDROID_WDIR
+ rm $file
+ file=$ANDROID_WDIR/$(basename $file)
+ fi
+ if ! [ -z $BSD_WDIR ]; then
+ $MYSSH mkdir -p $BSD_WDIR
+ ssh_copy $file $BSD_WDIR
+ rm $file
+ file=$BSD_WDIR/$(basename $file)
+ fi
+
+ export_vars file
+}
+
+function cleanfs()
+{
+ set -e
+
+ if ! [ -z $ANDROID_WDIR ]; then
+ adb shell rm $1
+ adb shell rm $ANDROID_WDIR/disk
+ elif ! [ -z $BSD_WDIR ]; then
+ $MYSSH rm $1
+ $MYSSH rm $BSD_WDIR/disk
+ else
+ rm $1
+ fi
+}
+
+if [ "$1" = "-t" ]; then
+ shift
+ fstype=$1
+ shift
+fi
+
+if [ -z "$fstype" ]; then
+ fstype="ext4"
+fi
+
+if [ -z $(which mkfs.$fstype) ]; then
+ echo "no mkfs.$fstype command"
+ exit 0
+fi
+
+prepfs $fstype
+${OUTPUT}/disk -d $file -t $fstype $@
+cleanfs $file
+
diff --git a/tools/um/include/lkl.h b/tools/um/include/lkl.h
index 97da2d11502f..1cfa228880d4 100644
--- a/tools/um/include/lkl.h
+++ b/tools/um/include/lkl.h
@@ -120,6 +120,16 @@ static inline long lkl_sys_creat(const char *file, int mode)
}
#endif
+#ifdef __lkl__NR_faccessat
+/**
+ * lkl_sys_access - wrapper for lkl_sys_faccessat
+ */
+static inline long lkl_sys_access(const char *file, int mode)
+{
+ return lkl_sys_faccessat(LKL_AT_FDCWD, file, mode);
+}
+#endif
+
#ifdef __lkl__NR_mkdirat
/**
* lkl_sys_mkdir - wrapper for lkl_sys_mkdirat
@@ -130,6 +140,36 @@ static inline long lkl_sys_mkdir(const char *path, mode_t mode)
}
#endif
+#ifdef __lkl__NR_unlinkat
+/**
+ * lkl_sys_rmdir - wrapper for lkl_sys_unlinkrat
+ */
+static inline long lkl_sys_rmdir(const char *path)
+{
+ return lkl_sys_unlinkat(LKL_AT_FDCWD, path, LKL_AT_REMOVEDIR);
+}
+#endif
+
+#ifdef __lkl__NR_unlinkat
+/**
+ * lkl_sys_unlink - wrapper for lkl_sys_unlinkat
+ */
+static inline long lkl_sys_unlink(const char *path)
+{
+ return lkl_sys_unlinkat(LKL_AT_FDCWD, path, 0);
+}
+#endif
+
+#ifdef __lkl__NR_mknodat
+/**
+ * lkl_sys_mknod - wrapper for lkl_sys_mknodat
+ */
+static inline long lkl_sys_mknod(const char *path, mode_t mode, dev_t dev)
+{
+ return lkl_sys_mknodat(LKL_AT_FDCWD, path, mode, dev);
+}
+#endif
+
#ifdef __lkl__NR_epoll_create1
/**
* lkl_sys_epoll_create - wrapper for lkl_sys_epoll_create1
@@ -151,6 +191,172 @@ static inline long lkl_sys_epoll_wait(int fd, struct lkl_epoll_event *ev,
}
#endif
+/**
+ * struct lkl_dev_blk_ops - block device host operations, defined in lkl_host.h.
+ */
+struct lkl_dev_blk_ops;
+
+/**
+ * lkl_disk - host disk handle
+ *
+ * @dev - a pointer to private information for this disk backend
+ * @fd - a POSIX file descriptor that can be used by preadv/pwritev
+ * @handle - an NT file handle that can be used by ReadFile/WriteFile
+ */
+struct lkl_disk {
+ void *dev;
+ union {
+ int fd;
+ void *handle;
+ };
+ struct lkl_dev_blk_ops *ops;
+};
+
+/**
+ * lkl_disk_add - add a new disk
+ *
+ * @disk - the host disk handle
+ * @returns a disk id (0 is valid) or a strictly negative value in case of error
+ */
+int lkl_disk_add(struct lkl_disk *disk);
+
+/**
+ * lkl_disk_remove - remove a disk
+ *
+ * This function makes a cleanup of the @disk's private information
+ * that was initialized by lkl_disk_add before.
+ *
+ * @disk - the host disk handle
+ */
+int lkl_disk_remove(struct lkl_disk disk);
+
+/**
+ * lkl_encode_dev_from_sysfs_blkdev - extract device id from sysfs
+ *
+ * This function returns the device id for the given sysfs dev node.
+ * The content of the node has to be in the form 'MAJOR:MINOR'.
+ * Also, this function expects an absolute path which means that sysfs
+ * already has to be mounted at the given path
+ *
+ * @sysfs_path - absolute path to the sysfs dev node
+ * @pdevid - pointer to memory where dev id will be returned
+ * @returns - 0 on success, a negative value on error
+ */
+int lkl_encode_dev_from_sysfs(const char *sysfs_path, uint32_t *pdevid);
+
+/**
+ * lkl_mount_dev - mount a disk
+ *
+ * This functions creates a device file for the given disk, creates a mount
+ * point and mounts the device over the mount point.
+ *
+ * @disk_id - the disk id identifying the disk to be mounted
+ * @part - disk partition or zero for full disk
+ * @fs_type - filesystem type
+ * @flags - mount flags
+ * @opts - additional filesystem specific mount options
+ * @mnt_str - a string that will be filled by this function with the path where
+ * the filesystem has been mounted
+ * @mnt_str_len - size of mnt_str
+ * @returns - 0 on success, a negative value on error
+ */
+long lkl_mount_dev(unsigned int disk_id, unsigned int part, const char *fs_type,
+ int flags, const char *opts,
+ char *mnt_str, unsigned int mnt_str_len);
+
+/**
+ * lkl_umount_dev - umount a disk
+ *
+ * This functions umounts the given disks and removes the device file and the
+ * mount point.
+ *
+ * @disk_id - the disk id identifying the disk to be mounted
+ * @part - disk partition or zero for full disk
+ * @flags - umount flags
+ * @timeout_ms - timeout to wait for the kernel to flush closed files so that
+ * umount can succeed
+ * @returns - 0 on success, a negative value on error
+ */
+long lkl_umount_dev(unsigned int disk_id, unsigned int part, int flags,
+ long timeout_ms);
+
+/**
+ * lkl_umount_timeout - umount filesystem with timeout
+ *
+ * @path - the path to unmount
+ * @flags - umount flags
+ * @timeout_ms - timeout to wait for the kernel to flush closed files so that
+ * umount can succeed
+ * @returns - 0 on success, a negative value on error
+ */
+long lkl_umount_timeout(char *path, int flags, long timeout_ms);
+
+/**
+ * lkl_opendir - open a directory
+ *
+ * @path - directory path
+ * @err - pointer to store the error in case of failure
+ * @returns - a handle to be used when calling lkl_readdir
+ */
+struct lkl_dir *lkl_opendir(const char *path, int *err);
+
+/**
+ * lkl_fdopendir - open a directory
+ *
+ * @fd - file descriptor
+ * @err - pointer to store the error in case of failure
+ * @returns - a handle to be used when calling lkl_readdir
+ */
+struct lkl_dir *lkl_fdopendir(int fd, int *err);
+
+/**
+ * lkl_rewinddir - reset directory stream
+ *
+ * @dir - the directory handler as returned by lkl_opendir
+ */
+void lkl_rewinddir(struct lkl_dir *dir);
+
+/**
+ * lkl_closedir - close the directory
+ *
+ * @dir - the directory handler as returned by lkl_opendir
+ */
+int lkl_closedir(struct lkl_dir *dir);
+
+/**
+ * lkl_readdir - get the next available entry of the directory
+ *
+ * @dir - the directory handler as returned by lkl_opendir
+ * @returns - a lkl_dirent64 entry or NULL if the end of the directory stream is
+ * reached or if an error occurred; check lkl_errdir() to distinguish between
+ * errors or end of the directory stream
+ */
+struct lkl_linux_dirent64 *lkl_readdir(struct lkl_dir *dir);
+
+/**
+ * lkl_errdir - checks if an error occurred during the last lkl_readdir call
+ *
+ * @dir - the directory handler as returned by lkl_opendir
+ * @returns - 0 if no error occurred, or a negative value otherwise
+ */
+int lkl_errdir(struct lkl_dir *dir);
+
+/**
+ * lkl_dirfd - gets the file descriptor associated with the directory handle
+ *
+ * @dir - the directory handle as returned by lkl_opendir
+ * @returns - a positive value,which is the LKL file descriptor associated with
+ * the directory handle, or a negative value otherwise
+ */
+int lkl_dirfd(struct lkl_dir *dir);
+
+/**
+ * lkl_mount_fs - mount a file system type like proc, sys
+ * @fstype - file system type. e.g. proc, sys
+ * @returns - 0 on success. 1 if it's already mounted. negative on failure.
+ */
+int lkl_mount_fs(char *fstype);
+
#ifdef __cplusplus
}
#endif
diff --git a/tools/um/include/lkl_host.h b/tools/um/include/lkl_host.h
index 5fe7a64dc4dd..1a2794ef47a0 100644
--- a/tools/um/include/lkl_host.h
+++ b/tools/um/include/lkl_host.h
@@ -10,6 +10,7 @@ extern "C" {
#include <lkl.h>
extern struct lkl_host_operations lkl_host_ops;
+extern char lkl_um_devs[4096];
#ifdef __cplusplus
}
diff --git a/tools/um/lib/Build b/tools/um/lib/Build
index dddff26a3b4e..29491b40746c 100644
--- a/tools/um/lib/Build
+++ b/tools/um/lib/Build
@@ -4,3 +4,4 @@ CFLAGS_posix-host.o += -D_FILE_OFFSET_BITS=64
liblinux-$(CONFIG_UMMODE_LIB) += utils.o
liblinux-$(CONFIG_UMMODE_LIB) += posix-host.o
liblinux-$(CONFIG_UMMODE_LIB) += jmp_buf.o
+liblinux-$(CONFIG_UMMODE_LIB) += fs.o
diff --git a/tools/um/lib/fs.c b/tools/um/lib/fs.c
new file mode 100644
index 000000000000..352b25f0c56f
--- /dev/null
+++ b/tools/um/lib/fs.c
@@ -0,0 +1,461 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <stdarg.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <lkl_host.h>
+
+#define MAX_FSTYPE_LEN 50
+
+static struct lkl_disk *lkl_disks[16];
+static int registered_blk_dev_idx;
+
+static int lkl_disk_um_add(struct lkl_disk *disk, const char *blkparams)
+{
+ /* concat strings */
+ snprintf(lkl_um_devs + strlen(lkl_um_devs), sizeof(lkl_um_devs),
+ " ubd%d=%s", registered_blk_dev_idx, blkparams);
+
+ return registered_blk_dev_idx++;
+}
+
+int lkl_disk_add(struct lkl_disk *disk)
+{
+ int ret = -1;
+
+ ret = lkl_disk_um_add(disk, disk->dev);
+
+ lkl_disks[ret] = disk;
+
+ return ret;
+}
+
+int lkl_disk_remove(struct lkl_disk disk)
+{
+ /* FIXME */
+ return 0;
+}
+
+int lkl_mount_fs(char *fstype)
+{
+ char dir[MAX_FSTYPE_LEN+2] = "/";
+ int flags = 0, ret = 0;
+
+ strncat(dir, fstype, MAX_FSTYPE_LEN);
+
+ /* Create with regular umask */
+ ret = lkl_sys_mkdir(dir, 0xff);
+ if (ret && ret != -LKL_EEXIST) {
+ lkl_perror("mount_fs mkdir", ret);
+ return ret;
+ }
+
+ /* We have no use for nonzero flags right now */
+ ret = lkl_sys_mount("none", dir, fstype, flags, NULL);
+ if (ret && ret != -LKL_EBUSY) {
+ lkl_sys_rmdir(dir);
+ return ret;
+ }
+
+ if (ret == -LKL_EBUSY)
+ return 1;
+ return 0;
+}
+
+static uint32_t new_encode_dev(unsigned int major, unsigned int minor)
+{
+ return (minor & 0xff) | (major << 8) | ((minor & ~0xff) << 12);
+}
+
+static int startswith(const char *str, const char *pre)
+{
+ return strncmp(pre, str, strlen(pre)) == 0;
+}
+
+static int get_node_with_prefix(const char *path, const char *prefix,
+ char *result, unsigned int result_len)
+{
+ struct lkl_dir *dir = NULL;
+ struct lkl_linux_dirent64 *dirent;
+ int ret;
+
+ dir = lkl_opendir(path, &ret);
+ if (!dir)
+ return ret;
+
+ ret = -LKL_ENOENT;
+
+ while ((dirent = lkl_readdir(dir))) {
+ if (startswith(dirent->d_name, prefix)) {
+ if (strlen(dirent->d_name) + 1 > result_len) {
+ ret = -LKL_ENOMEM;
+ break;
+ }
+ memcpy(result, dirent->d_name, strlen(dirent->d_name));
+ result[strlen(dirent->d_name)] = '\0';
+ ret = 0;
+ break;
+ }
+ }
+
+ lkl_closedir(dir);
+
+ return ret;
+}
+
+int lkl_encode_dev_from_sysfs(const char *sysfs_path, uint32_t *pdevid)
+{
+ int ret;
+ long fd;
+ int major, minor;
+ char buf[16] = { 0, };
+ char *bufptr;
+
+ fd = lkl_sys_open(sysfs_path, LKL_O_RDONLY, 0);
+ if (fd < 0)
+ return fd;
+
+ ret = lkl_sys_read(fd, buf, sizeof(buf));
+ if (ret < 0)
+ goto out_close;
+
+ if (ret == sizeof(buf)) {
+ ret = -LKL_ENOBUFS;
+ goto out_close;
+ }
+
+ bufptr = strchr(buf, ':');
+ if (bufptr == NULL) {
+ ret = -LKL_EINVAL;
+ goto out_close;
+ }
+ bufptr[0] = '\0';
+ bufptr++;
+
+ major = atoi(buf);
+ minor = atoi(bufptr);
+
+ *pdevid = new_encode_dev(major, minor);
+ ret = 0;
+
+out_close:
+ lkl_sys_close(fd);
+
+ return ret;
+}
+
+#define SYSFS_DEV_UMBLK_CMDLINE_PATH \
+ "/sysfs/devices/platform/uml-blkdev.%d"
+
+struct abuf {
+ char *mem, *ptr;
+ unsigned int len;
+};
+
+static int snprintf_append(struct abuf *buf, const char *fmt, ...)
+{
+ int ret;
+ va_list args;
+
+ if (!buf->ptr)
+ buf->ptr = buf->mem;
+
+ va_start(args, fmt);
+ ret = vsnprintf(buf->ptr, buf->len - (buf->ptr - buf->mem), fmt, args);
+ va_end(args);
+
+ if (ret < 0 || (ret >= (int)(buf->len - (buf->ptr - buf->mem))))
+ return -LKL_ENOMEM;
+
+ buf->ptr += ret;
+
+ return 0;
+}
+
+static int __lkl_get_blkdev(int disk_id, unsigned int part, uint32_t *pdevid,
+ const char *sysfs_path_fmt, const char *drv_prefix,
+ const char *disk_prefix)
+{
+ char sysfs_path[LKL_PATH_MAX];
+ char drv_name[LKL_PATH_MAX];
+ char disk_name[LKL_PATH_MAX];
+ struct abuf sysfs_path_buf = {
+ .mem = sysfs_path,
+ .len = sizeof(sysfs_path),
+ };
+ int ret;
+
+ if (disk_id < 0)
+ return -LKL_EINVAL;
+
+ ret = lkl_mount_fs("sysfs");
+ if (ret < 0)
+ return ret;
+
+ ret = snprintf_append(&sysfs_path_buf, sysfs_path_fmt, disk_id);
+ if (ret)
+ return ret;
+
+ ret = get_node_with_prefix(sysfs_path, drv_prefix, drv_name,
+ sizeof(drv_name));
+ if (ret)
+ return ret;
+
+ ret = snprintf_append(&sysfs_path_buf, "/%s/block", drv_name);
+ if (ret)
+ return ret;
+
+ ret = get_node_with_prefix(sysfs_path, disk_prefix, disk_name,
+ sizeof(disk_name));
+ if (ret)
+ return ret;
+
+ if (!part)
+ ret = snprintf_append(&sysfs_path_buf, "/%s/dev", disk_name);
+ else
+ ret = snprintf_append(&sysfs_path_buf, "/%s/%s%d/dev",
+ disk_name, disk_name, part);
+ if (ret)
+ return ret;
+
+ return lkl_encode_dev_from_sysfs(sysfs_path, pdevid);
+}
+
+int lkl_get_blkdev(int disk_id, unsigned int part, uint32_t *pdevid)
+{
+ char *fmt;
+
+ fmt = SYSFS_DEV_UMBLK_CMDLINE_PATH;
+ return __lkl_get_blkdev(disk_id, part, pdevid, fmt, "", "ubd");
+}
+
+long lkl_mount_dev(unsigned int disk_id, unsigned int part,
+ const char *fs_type, int flags,
+ const char *data, char *mnt_str, unsigned int mnt_str_len)
+{
+ char dev_str[] = { "/dev/xxxxxxxx" };
+ unsigned int dev;
+ int err;
+ char _data[4096]; /* FIXME: PAGE_SIZE is not exported by LKL */
+
+ if (mnt_str_len < sizeof(dev_str))
+ return -LKL_ENOMEM;
+
+ err = lkl_get_blkdev(disk_id, part, &dev);
+ if (err < 0)
+ return err;
+
+ snprintf(dev_str, sizeof(dev_str), "/dev/%08x", dev);
+ snprintf(mnt_str, mnt_str_len, "/mnt/%08x", dev);
+
+ err = lkl_sys_access("/dev", LKL_S_IRWXO);
+ if (err < 0) {
+ if (err == -LKL_ENOENT)
+ err = lkl_sys_mkdir("/dev", 0700);
+ if (err < 0)
+ return err;
+ }
+
+ err = lkl_sys_mknod(dev_str, LKL_S_IFBLK | 0600, dev);
+ if (err < 0)
+ return err;
+
+ err = lkl_sys_access("/mnt", LKL_S_IRWXO);
+ if (err < 0) {
+ if (err == -LKL_ENOENT)
+ err = lkl_sys_mkdir("/mnt", 0700);
+ if (err < 0)
+ return err;
+ }
+
+ err = lkl_sys_mkdir(mnt_str, 0700);
+ if (err < 0) {
+ lkl_sys_unlink(dev_str);
+ return err;
+ }
+
+ /* kernel always copies a full page */
+ if (data) {
+ strncpy(_data, data, sizeof(_data));
+ _data[sizeof(_data) - 1] = 0;
+ } else {
+ _data[0] = 0;
+ }
+
+ err = lkl_sys_mount(dev_str, mnt_str, (char *)fs_type, flags, _data);
+ if (err < 0) {
+ lkl_sys_unlink(dev_str);
+ lkl_sys_rmdir(mnt_str);
+ return err;
+ }
+
+ return 0;
+}
+
+long lkl_umount_timeout(char *path, int flags, long timeout_ms)
+{
+ long incr = 10000000; /* 10 ms */
+ struct lkl_timespec ts = {
+ .tv_sec = 0,
+ .tv_nsec = incr,
+ };
+ long err;
+
+ do {
+ err = lkl_sys_umount(path, flags);
+ if (err == -LKL_EBUSY) {
+ lkl_sys_nanosleep((struct __lkl__kernel_timespec *)&ts,
+ NULL);
+ timeout_ms -= incr / 1000000;
+ }
+ } while (err == -LKL_EBUSY && timeout_ms > 0);
+
+ return err;
+}
+
+long lkl_umount_dev(unsigned int disk_id, unsigned int part, int flags,
+ long timeout_ms)
+{
+ char dev_str[] = { "/dev/xxxxxxxx" };
+ char mnt_str[] = { "/mnt/xxxxxxxx" };
+ unsigned int dev;
+ int err;
+
+ err = lkl_get_blkdev(disk_id, part, &dev);
+ if (err < 0)
+ return err;
+
+ snprintf(dev_str, sizeof(dev_str), "/dev/%08x", dev);
+ snprintf(mnt_str, sizeof(mnt_str), "/mnt/%08x", dev);
+
+ err = lkl_umount_timeout(mnt_str, flags, timeout_ms);
+ if (err)
+ return err;
+
+ err = lkl_sys_unlink(dev_str);
+ if (err)
+ return err;
+
+ return lkl_sys_rmdir(mnt_str);
+}
+
+struct lkl_dir {
+ int fd;
+ char buf[1024];
+ char *pos;
+ int len;
+};
+
+static struct lkl_dir *lkl_dir_alloc(int *err)
+{
+ struct lkl_dir *dir = lkl_mem_alloc(sizeof(struct lkl_dir));
+
+ if (!dir) {
+ *err = -LKL_ENOMEM;
+ return NULL;
+ }
+
+ dir->len = 0;
+ dir->pos = NULL;
+
+ return dir;
+}
+
+struct lkl_dir *lkl_opendir(const char *path, int *err)
+{
+ struct lkl_dir *dir = lkl_dir_alloc(err);
+
+ if (!dir) {
+ *err = -LKL_ENOMEM;
+ return NULL;
+ }
+
+ dir->fd = lkl_sys_open(path, LKL_O_RDONLY | LKL_O_DIRECTORY, 0);
+ if (dir->fd < 0) {
+ *err = dir->fd;
+ lkl_mem_free(dir);
+ return NULL;
+ }
+
+ *err = 0;
+
+ return dir;
+}
+
+struct lkl_dir *lkl_fdopendir(int fd, int *err)
+{
+ struct lkl_dir *dir = lkl_dir_alloc(err);
+
+ if (!dir)
+ return NULL;
+
+ dir->fd = fd;
+
+ return dir;
+}
+
+void lkl_rewinddir(struct lkl_dir *dir)
+{
+ lkl_sys_lseek(dir->fd, 0, LKL_SEEK_SET);
+ dir->len = 0;
+ dir->pos = NULL;
+}
+
+int lkl_closedir(struct lkl_dir *dir)
+{
+ int ret;
+
+ ret = lkl_sys_close(dir->fd);
+ lkl_mem_free(dir);
+
+ return ret;
+}
+
+struct lkl_linux_dirent64 *lkl_readdir(struct lkl_dir *dir)
+{
+ struct lkl_linux_dirent64 *de;
+
+ if (dir->len < 0)
+ return NULL;
+
+ if (!dir->pos || dir->pos - dir->buf >= dir->len)
+ goto read_buf;
+
+return_de:
+ de = (struct lkl_linux_dirent64 *)dir->pos;
+ dir->pos += de->d_reclen;
+
+ return de;
+
+read_buf:
+ dir->pos = NULL;
+ de = (struct lkl_linux_dirent64 *)dir->buf;
+ dir->len = lkl_sys_getdents64(dir->fd, de, sizeof(dir->buf));
+ if (dir->len <= 0)
+ return NULL;
+
+ dir->pos = dir->buf;
+ goto return_de;
+}
+
+int lkl_errdir(struct lkl_dir *dir)
+{
+ if (dir->len >= 0)
+ return 0;
+
+ return dir->len;
+}
+
+int lkl_dirfd(struct lkl_dir *dir)
+{
+ return dir->fd;
+}
+
+int lkl_set_fd_limit(unsigned int fd_limit)
+{
+ struct lkl_rlimit rlim = {
+ .rlim_cur = fd_limit,
+ .rlim_max = fd_limit,
+ };
+ return lkl_sys_setrlimit(LKL_RLIMIT_NOFILE, &rlim);
+}
diff --git a/tools/um/lib/posix-host.c b/tools/um/lib/posix-host.c
index f7c170fd3fd9..5fc7d6822a7f 100644
--- a/tools/um/lib/posix-host.c
+++ b/tools/um/lib/posix-host.c
@@ -268,5 +268,6 @@ void *lkl_tls_get(struct lkl_tls_key *key)
}
struct lkl_host_operations lkl_host_ops = {
+ .um_devices = lkl_um_devs,
};
diff --git a/tools/um/lib/utils.c b/tools/um/lib/utils.c
index 3b38e1a95124..03841f70f73e 100644
--- a/tools/um/lib/utils.c
+++ b/tools/um/lib/utils.c
@@ -4,6 +4,8 @@
#include <string.h>
#include <lkl_host.h>
+char lkl_um_devs[4096];
+
static const char * const lkl_err_strings[] = {
[0] = "Success",
[LKL_EPERM] = "Operation not permitted",
--
2.21.0 (Apple Git-122.2)
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