nvme-cli: fabrics: remove libudev dependency

I get a lot of complaints about portability of the nvme-cli regarding the
libudev dependency. This patch removes the dependency from the fabrics
disconnect command when using the target nqn method. Tested on nvme
loop target.

Signed-off-by: Keith Busch <keith.busch@intel.com>

diff --git a/Makefile b/Makefile
index 77945efaee9787064e840694442e594797d7929b..a8acd3fccab08f63daecebc5b151ef9fea8546f6 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -7,7 +7,6 @@ DESTDIR =
 PREFIX ?= /usr/local
 SYSCONFDIR = /etc
 SBINDIR = $(PREFIX)/sbin
-LIBUDEV := $(shell ld -o /dev/null -ludev >/dev/null 2>&1; echo $$?)
 LIB_DEPENDS =
 
 RPMBUILD = rpmbuild
@@ -16,12 +15,6 @@ RM = rm -f
 
 AUTHOR=Keith Busch <keith.busch@intel.com>
 
-ifeq ($(LIBUDEV),0)
-       override LDFLAGS += -ludev
-       override CFLAGS  += -DLIBUDEV_EXISTS
-       override LIB_DEPENDS += udev
-endif
-
 default: $(NVME)
 
 NVME-VERSION-FILE: FORCE

diff --git a/fabrics.c b/fabrics.c
index 2b3caa14b24cdefcefb8a05ea9176bff186b3083..d62373fd30156305c51b7d3f57e29b3598bdbd0f 100644 (file)
--- a/fabrics.c
+++ b/fabrics.c
@@ -26,13 +26,10 @@
 #include <stdbool.h>
 #include <stdint.h>
 #include <unistd.h>
+#include <dirent.h>
 #include <sys/ioctl.h>
 #include <asm/byteorder.h>
 #include <inttypes.h>
-#ifdef LIBUDEV_EXISTS
-#include <libudev.h>
-#endif
-
 #include <linux/types.h>
 
 #include "parser.h"
@@ -62,6 +59,7 @@ static struct config {
 #define PATH_NVME_FABRICS      "/dev/nvme-fabrics"
 #define PATH_NVMF_DISC         "/etc/nvme/discovery.conf"
 #define PATH_NVMF_HOSTNQN      "/etc/nvme/hostnqn"
+#define SYS_NVME               "/sys/class/nvme"
 #define MAX_DISC_ARGS          10
 
 enum {
@@ -801,85 +799,64 @@ int connect(const char *desc, int argc, char **argv)
        return 0;
 }
 
-#ifdef LIBUDEV_EXISTS
-static int disconnect_subsys(struct udev_enumerate *enumerate, char *nqn)
+static int scan_sys_nvme_filter(const struct dirent *d)
 {
-       struct udev_list_entry *list_entry;
-       const char *subsysnqn;
-       char *sysfs_path;
-       int ret = 1;
-
-       udev_list_entry_foreach(list_entry,
-                               udev_enumerate_get_list_entry(enumerate)) {
-               struct udev_device *device;
-
-               device = udev_device_new_from_syspath(
-                               udev_enumerate_get_udev(enumerate),
-                               udev_list_entry_get_name(list_entry));
-               if (device != NULL) {
-                       subsysnqn = udev_device_get_sysattr_value(
-                                       device, "subsysnqn");
-                       if (subsysnqn && !strcmp(subsysnqn, nqn)) {
-                               if (asprintf(&sysfs_path,
-                                       "%s/delete_controller",
-                                       udev_device_get_syspath(device)) < 0) {
-                                       ret = errno;
-                                       udev_device_unref(device);
-                                       break;
-                               }
-                               udev_device_unref(device);
-                               ret = remove_ctrl_by_path(sysfs_path);
-                               free(sysfs_path);
-                               break;
-                       }
-                       udev_device_unref(device);
-               }
-       }
-
-       return ret;
+       if (!strcmp(d->d_name, "."))
+               return 0;
+       if (!strcmp(d->d_name, ".."))
+               return 0;
+       return 1;
 }
 
-static int disconnect_by_nqn(char *nqn)
+static int disconnect_subsys(char *nqn, char *ctrl)
 {
-       struct udev *udev;
-       struct udev_enumerate *udev_enumerate;
-       int ret;
+       char *sysfs_nqn_path, *sysfs_del_path;;
+       char subsysnqn[NVMF_NQN_SIZE] = {};
+       int fd, ret = 0;
 
-       if (strlen(nqn) > NVMF_NQN_SIZE) {
-               ret = -EINVAL;
-               goto exit;
-       }
+       asprintf(&sysfs_nqn_path, "%s/%s/subsysnqn", SYS_NVME, ctrl);
+       asprintf(&sysfs_del_path, "%s/%s/delete_controller", SYS_NVME, ctrl);
 
-       udev = udev_new();
-       if (!udev) {
-               fprintf(stderr, "failed to create udev\n");
-               ret = -ENOMEM;
-               goto exit;
-       }
+       fd = open(sysfs_nqn_path, O_RDONLY);
+       if (fd < 0)
+               goto free;
 
-       udev_enumerate = udev_enumerate_new(udev);
-       if (udev_enumerate == NULL) {
-               ret = -ENOMEM;
-               goto free_udev;
-       }
+       if (read(fd, subsysnqn, NVMF_NQN_SIZE) < 0)
+               goto close;
 
-       udev_enumerate_add_match_subsystem(udev_enumerate, "nvme");
-       udev_enumerate_scan_devices(udev_enumerate);
-       ret = disconnect_subsys(udev_enumerate, nqn);
-       udev_enumerate_unref(udev_enumerate);
+       subsysnqn[strcspn(subsysnqn, "\n")] = '\0';
+       if (strcmp(subsysnqn, nqn))
+               goto close;
 
-free_udev:
-       udev_unref(udev);
-exit:
+       ret = remove_ctrl_by_path(sysfs_del_path);
+ close:
+       close(fd);
+ free:
+       free(sysfs_del_path);
+       free(sysfs_nqn_path);
        return ret;
 }
-#else
+
 static int disconnect_by_nqn(char *nqn)
 {
-       fprintf(stderr, "libudev not detected, install and rebuild.\n");
-       return -1;
+       struct dirent **devices = NULL;
+       int i, n, ret = 0;
+
+       if (strlen(nqn) > NVMF_NQN_SIZE)
+               return -EINVAL;
+
+       n = scandir(SYS_NVME, &devices, scan_sys_nvme_filter, alphasort);
+       if (n < 0)
+               return n;
+
+       for (i = 0; i < n; i++)
+               ret = disconnect_subsys(nqn, devices[i]->d_name);
+
+       for (i = 0; i < n; i++)
+               free(devices[i]);
+       free(devices);
+       return ret;
 }
-#endif
 
 static int disconnect_by_device(char *device)
 {