selftests/powerpc: Add {read,write}_{long,ulong}

Add helper functions to read and write (unsigned) long values directly
from/to files. One of the kernel interfaces uses hex strings, so we need
to allow passing a base too.

Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230203003947.38033-5-bgray@linux.ibm.com

diff --git a/tools/testing/selftests/powerpc/dscr/dscr.h b/tools/testing/selftests/powerpc/dscr/dscr.h
index aaa2b0d..2c54998 100644 (file)
--- a/tools/testing/selftests/powerpc/dscr/dscr.h
+++ b/tools/testing/selftests/powerpc/dscr/dscr.h
@@ -65,26 +65,21 @@ inline void set_dscr_usr(unsigned long val)
 unsigned long get_default_dscr(void)
 {
        int err;
-       char buf[16] = {0};
        unsigned long val;
 
-       err = read_file(DSCR_DEFAULT, buf, sizeof(buf) - 1, NULL);
+       err = read_ulong(DSCR_DEFAULT, &val, 16);
        if (err) {
                perror("read() failed");
                exit(1);
        }
-       sscanf(buf, "%lx", &val);
        return val;
 }
 
 void set_default_dscr(unsigned long val)
 {
        int err;
-       char buf[16];
 
-       sprintf(buf, "%lx\n", val);
-
-       err = write_file(DSCR_DEFAULT, buf, strlen(buf));
+       err = write_ulong(DSCR_DEFAULT, val, 16);
        if (err) {
                perror("write() failed");
                exit(1);

diff --git a/tools/testing/selftests/powerpc/dscr/dscr_sysfs_test.c b/tools/testing/selftests/powerpc/dscr/dscr_sysfs_test.c
index c350f19..4f1fef6 100644 (file)
--- a/tools/testing/selftests/powerpc/dscr/dscr_sysfs_test.c
+++ b/tools/testing/selftests/powerpc/dscr/dscr_sysfs_test.c
@@ -12,16 +12,16 @@
 
 static int check_cpu_dscr_default(char *file, unsigned long val)
 {
-       char buf[10] = {0};
-       int rc;
+       unsigned long cpu_dscr;
+       int err;
 
-       rc = read_file(file, buf, sizeof(buf) - 1, NULL);
-       if (rc)
-               return rc;
+       err = read_ulong(file, &cpu_dscr, 16);
+       if (err)
+               return err;
 
-       if (strtol(buf, NULL, 16) != val) {
+       if (cpu_dscr != val) {
                printf("DSCR match failed: %ld (system) %ld (cpu)\n",
-                                       val, strtol(buf, NULL, 16));
+                                       val, cpu_dscr);
                return 1;
        }
        return 0;

diff --git a/tools/testing/selftests/powerpc/include/utils.h b/tools/testing/selftests/powerpc/include/utils.h
index 7c1fa38..311ddc1 100644 (file)
--- a/tools/testing/selftests/powerpc/include/utils.h
+++ b/tools/testing/selftests/powerpc/include/utils.h
@@ -42,6 +42,10 @@ int parse_ulong(const char *buffer, size_t count, unsigned long *result, int bas
 
 int read_file(const char *path, char *buf, size_t count, size_t *len);
 int write_file(const char *path, const char *buf, size_t count);
+int read_long(const char *path, long *result, int base);
+int write_long(const char *path, long result, int base);
+int read_ulong(const char *path, unsigned long *result, int base);
+int write_ulong(const char *path, unsigned long result, int base);
 int read_debugfs_file(const char *debugfs_file, char *buf, size_t count);
 int write_debugfs_file(const char *debugfs_file, const char *buf, size_t count);
 int read_debugfs_int(const char *debugfs_file, int *result);

diff --git a/tools/testing/selftests/powerpc/pmu/lib.c b/tools/testing/selftests/powerpc/pmu/lib.c
index 1cfc13a..719f94f 100644 (file)
--- a/tools/testing/selftests/powerpc/pmu/lib.c
+++ b/tools/testing/selftests/powerpc/pmu/lib.c
@@ -192,15 +192,8 @@ bool require_paranoia_below(int level)
 {
        int err;
        long current;
-       char buf[16] = {0};
 
-       err = read_file(PARANOID_PATH, buf, sizeof(buf) - 1, NULL);
-       if (err) {
-               printf("Couldn't read " PARANOID_PATH "?\n");
-               return false;
-       }
-
-       err = parse_long(buf, sizeof(buf), &current, 10);
+       err = read_long(PARANOID_PATH, &current, 10);
        if (err) {
                printf("Couldn't parse " PARANOID_PATH "?\n");
                return false;

diff --git a/tools/testing/selftests/powerpc/utils.c b/tools/testing/selftests/powerpc/utils.c
index ddfd871..1017f17 100644 (file)
--- a/tools/testing/selftests/powerpc/utils.c
+++ b/tools/testing/selftests/powerpc/utils.c
@@ -245,6 +245,87 @@ int parse_ulong(const char *buffer, size_t count, unsigned long *result, int bas
        return err;
 }
 
+int read_long(const char *path, long *result, int base)
+{
+       int err;
+       char buffer[32] = {0};
+
+       err = read_file(path, buffer, sizeof(buffer) - 1, NULL);
+       if (err)
+               return err;
+
+       return parse_long(buffer, sizeof(buffer), result, base);
+}
+
+int read_ulong(const char *path, unsigned long *result, int base)
+{
+       int err;
+       char buffer[32] = {0};
+
+       err = read_file(path, buffer, sizeof(buffer) - 1, NULL);
+       if (err)
+               return err;
+
+       return parse_ulong(buffer, sizeof(buffer), result, base);
+}
+
+int write_long(const char *path, long result, int base)
+{
+       int err;
+       int len;
+       char buffer[32];
+
+       /* Decimal only for now: no format specifier for signed hex values */
+       if (base != 10) {
+               err = -EINVAL;
+               goto out;
+       }
+
+       len = snprintf(buffer, sizeof(buffer), "%ld", result);
+       if (len < 0 || len >= sizeof(buffer)) {
+               err = -EOVERFLOW;
+               goto out;
+       }
+
+       err = write_file(path, buffer, len);
+
+out:
+       errno = -err;
+       return err;
+}
+
+int write_ulong(const char *path, unsigned long result, int base)
+{
+       int err;
+       int len;
+       char buffer[32];
+       char *fmt;
+
+       switch (base) {
+       case 10:
+               fmt = "%lu";
+               break;
+       case 16:
+               fmt = "%lx";
+               break;
+       default:
+               err = -EINVAL;
+               goto out;
+       }
+
+       len = snprintf(buffer, sizeof(buffer), fmt, result);
+       if (len < 0 || len >= sizeof(buffer)) {
+               err = -errno;
+               goto out;
+       }
+
+       err = write_file(path, buffer, len);
+
+out:
+       errno = -err;
+       return err;
+}
+
 void *find_auxv_entry(int type, char *auxv)
 {
        ElfW(auxv_t) *p;