libdasd: Move get_host_access_count() to libdasd

Reading DASD specific sysfs attributes should be collected in one
library. Move get_host_access_count() to libdasd/dasd_sys.

Remove the old implementation and update any user accordingly.
Also, fix the build order for zdsfs.

Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>

dasdfmt/Makefile

@@ -4,7 +4,6 @@ all: dasdfmt
 
 libs =	$(rootdir)/libdasd/libdasd.a \
 	$(rootdir)/libvtoc/libvtoc.a \
-	$(rootdir)/libu2s/libu2s.a \
 	$(rootdir)/libutil/libutil.a
 
 dasdfmt: dasdfmt.o $(libs)

dasdfmt/dasdfmt.c

@@ -1394,7 +1394,7 @@ static void do_format_dasd(dasdfmt_info_t *info, char *devname,
 	if ((info->verbosity > 0) || !info->withoutprompt || info->testmode)
 		dasdfmt_print_info(info, devname, vlabel, cylinders, heads, p);
 
-	count = u2s_get_host_access_count(devname);
+	count = dasd_get_host_access_count(devname);
 	if (info->force_host) {
 		if (count > 1) {
 			ERRMSG_EXIT(EXIT_FAILURE,

dasdview/Makefile

@@ -7,7 +7,6 @@ all: dasdview
 libs =	$(rootdir)/libdasd/libdasd.a \
 	$(rootdir)/libzds/libzds.a \
 	$(rootdir)/libvtoc/libvtoc.a \
-	$(rootdir)/libu2s/libu2s.a \
 	$(rootdir)/libutil/libutil.a
 
 dasdview: dasdview.o $(libs)

dasdview/dasdview.c

@@ -28,7 +28,6 @@
 #include "lib/dasd_base.h"
 #include "lib/dasd_sys.h"
 #include "lib/libzds.h"
-#include "lib/u2s.h"
 #include "lib/util_base.h"
 #include "lib/util_opt.h"
 #include "lib/util_prg.h"

fdasd/fdasd.c

@@ -935,7 +935,7 @@ static void fdasd_verify_device(fdasd_anchor_t *anc, char *name)
 		fdasd_error(anc, device_verification_failed, err_str);
 	}
 
-	count = u2s_get_host_access_count(name);
+	count = dasd_get_host_access_count(name);
 	if (anc->force_host) {
 		if (count > 1) {
 			snprintf(err_str, ERROR_STRING_SIZE,

include/lib/dasd_sys.h

@@ -13,9 +13,9 @@
 #define LIB_DASD_SYS_H
 
 #include <stdio.h>
-#include "u2s.h"
 
 int dasd_sys_raw_track_access(char *);
 int dasd_reset_chpid(char *, char *);
+int dasd_get_host_access_count(char *device);
 
 #endif /* LIB_DASD_SYS_H */

include/lib/u2s.h

@@ -15,7 +15,5 @@
 #define U2S_BUS_ID_SIZE    32
 
 int u2s_getbusid(char *, char *);
-int u2s_read_attribute(char *, char *, char *, size_t);
-int u2s_get_host_access_count(char *);
 
 #endif /* LIB_U2S_H */

libdasd/dasd_sys.c

@@ -14,6 +14,7 @@
 
 #include "lib/dasd_base.h"
 #include "lib/dasd_sys.h"
+#include "lib/util_file.h"
 #include "lib/util_path.h"
 #include "lib/util_sys.h"
 
@@ -155,3 +156,33 @@ int dasd_reset_chpid(char *devnode, char *chpid_char)
 
 	return 0;
 }
+
+/**
+ * Read amount of host with access to \p device
+ *
+ * The \p device can be any valid relative or absolute path to a DASD device
+ * node, for example:
+ *
+ * - /dev/dasda
+ * - /dev/disk/by-path/ccw-0.0.bf20
+ *
+ * @param[in]	device	Device node of interest
+ *
+ * @retval	n	Number of hosts with access to \p device
+ * @retval	0	Value could not be determined
+ */
+int dasd_get_host_access_count(char *device)
+{
+	char busid[9];
+	char *path;
+	long value;
+
+	if (!util_sys_get_dev_addr(device, busid))
+		return 0;
+
+	path = util_path_sysfs("bus/ccw/devices/%s/host_access_count", busid);
+	util_file_read_l(&value, 10, path);
+	free(path);
+
+	return value;
+}

libu2s/u2s.c

@@ -290,45 +290,3 @@ int u2s_getbusid(char *devicenode, char *busid)
 
 	return rc;
 }
-
-/*
- * Attempts to find the sysfs entry for the given busid and reads
- * the contents of a specified attribute to the buffer
- */
-int u2s_read_attribute(char *busid, char *attribute, char *buffer,
-		       size_t count)
-{
-	char path[100];
-	int rc, fd;
-	ssize_t rcount;
-
-	rc = 0;
-	snprintf(path, sizeof(path), "/sys/bus/ccw/devices/%s/%s",
-		 busid, attribute);
-	fd = open(path, O_RDONLY);
-	if (fd < 0)
-		return errno;
-	rcount = read(fd, buffer, count);
-	if (rcount < 0)
-		rc = errno;
-	close(fd);
-	return rc;
-}
-
-int u2s_get_host_access_count(char *devicenode)
-{
-	char busid[BUSIDSIZE];
-	unsigned long value;
-	char buffer[10];
-	char *endp;
-
-	u2s_getbusid(devicenode, busid);
-	u2s_read_attribute(busid, "host_access_count", buffer, sizeof(buffer));
-
-	value = strtoul(buffer, &endp, 0);
-
-	if (endp == buffer)
-		return -EINVAL;
-
-	return value;
-}

libzds/libzds.c

@@ -20,8 +20,8 @@
 #include <stdlib.h>
 
 #include "lib/dasd_base.h"
+#include "lib/dasd_sys.h"
 #include "lib/libzds.h"
-#include "lib/u2s.h"
 #include "lib/vtoc.h"
 
 /** @cond PRIVATE */
@@ -3701,7 +3701,7 @@ int lzds_analyse_open_count(struct zdsroot *root, int warn)
 	int rc = 0;
 
 	util_list_iterate(root->dasdlist, dasd) {
-		value = u2s_get_host_access_count(dasd->device);
+		value = dasd_get_host_access_count(dasd->device);
 
 		if (value < 0) {
 			fprintf(stderr,

zdsfs/Makefile

@@ -2,9 +2,9 @@ include ../common.mak
 
 libs =	$(rootdir)/libzds/libzds.a \
 	$(rootdir)/libvtoc/libvtoc.a \
+	$(rootdir)/libdasd/libdasd.a \
 	$(rootdir)/libu2s/libu2s.a \
 	$(rootdir)/libutil/libutil.a \
-	$(rootdir)/libdasd/libdasd.a
 
 ifeq (${HAVE_FUSE},0)