nvme: Print full device path

Restore nvme-cli 1.x behavior to print the full path to the device
file. We assume that the devtmpfs is mounted under /dev which is the
case for any systemd based distro and a de-facto standard.

But SPDK users see their device populated under /dev/spdk have their
device file appear. So instead blindly prefix /dev do a stat to check
if the file exist.

If our educated guesses fail, don't add the full path. This should be
really a corner case and as long no one complains don't overengineer.

Signed-off-by: Daniel Wagner <dwagner@suse.de>

diff --git a/nvme-print.c b/nvme-print.c
index d7fd14ba967c3589338a82f2447afd43be182a15..2b50fd52355cf4350c8d3d511d342acce207a9d8 100644 (file)
--- a/nvme-print.c
+++ b/nvme-print.c
@@ -6909,9 +6909,51 @@ void nvme_show_lba_status(struct nvme_lba_status *list, unsigned long len,
        }
 }
 
+static void nvme_dev_full_path(nvme_ns_t n, char *path, size_t len)
+{
+       struct stat st;
+
+       snprintf(path, len, "/dev/%s", nvme_ns_get_name(n));
+       if (stat(path, &st) == 0)
+               return;
+
+       snprintf(path, len, "/dev/spdk/%s", nvme_ns_get_name(n));
+       if (stat(path, &st) == 0)
+               return;
+
+       /*
+        * We could start trying to search for it but let's make
+        * it simple and just don't show the path at all.
+        */
+       snprintf(path, len, "%s", nvme_ns_get_name(n));
+}
+
+static void nvme_generic_full_path(nvme_ns_t n, char *path, size_t len)
+{
+       int head_instance;
+       int instance;
+       struct stat st;
+
+       sscanf(nvme_ns_get_name(n), "nvme%dn%d", &instance, &head_instance);
+       snprintf(path, len, "/dev/ng%dn%d", instance, head_instance);
+
+       if (stat(path, &st) == 0)
+               return;
+
+       snprintf(path, len, "/dev/spkd/ng%dn%d", instance, head_instance);
+       if (stat(path, &st) == 0)
+               return;
+       /*
+        * We could start trying to search for it but let's make
+        * it simple and just don't show the path at all.
+        */
+       snprintf(path, len, "ng%dn%d", instance, head_instance);
+}
+
 void nvme_show_list_item(nvme_ns_t n)
 {
        char usage[128] = { 0 }, format[128] = { 0 };
+       char devname[128] = { 0 }; char genname[128] = { 0 };
 
        long long lba = nvme_ns_get_lba_size(n);
        double nsze = nvme_ns_get_lba_count(n) * lba;
@@ -6926,8 +6968,11 @@ void nvme_show_list_item(nvme_ns_t n)
        snprintf(format, sizeof(format), "%3.0f %2sB + %2d B", (double)lba,
                l_suffix, nvme_ns_get_meta_size(n));
 
+       nvme_dev_full_path(n, devname, sizeof(devname));
+       nvme_generic_full_path(n, genname, sizeof(genname));
+
        printf("%-21s %-21s %-20s %-40s %-9d %-26s %-16s %-8s\n",
-               nvme_ns_get_name(n), nvme_ns_get_generic_name(n), nvme_ns_get_serial(n),
+               devname, genname, nvme_ns_get_serial(n),
                nvme_ns_get_model(n), nvme_ns_get_nsid(n), usage, format,
                nvme_ns_get_firmware(n));
 }
@@ -6958,13 +7003,12 @@ static void nvme_show_simple_list(nvme_root_t r)
 
 static void nvme_show_ns_details(nvme_ns_t n)
 {
-       char usage[128] = { 0 }, format[128] = { 0 }, generic[128] = { 0 };
+       char usage[128] = { 0 }, format[128] = { 0 };
+       char devname[128] = { 0 }, genname[128] = { 0 };
 
        long long lba = nvme_ns_get_lba_size(n);
        double nsze = nvme_ns_get_lba_count(n) * lba;
        double nuse = nvme_ns_get_lba_util(n) * lba;
-       int instance;
-       int head_instance;
 
        const char *s_suffix = suffix_si_get(&nsze);
        const char *u_suffix = suffix_si_get(&nuse);
@@ -6974,11 +7018,11 @@ static void nvme_show_ns_details(nvme_ns_t n)
        sprintf(format,"%3.0f %2sB + %2d B", (double)lba, l_suffix,
                nvme_ns_get_meta_size(n));
 
-       sscanf(nvme_ns_get_name(n), "nvme%dn%d", &instance, &head_instance);
-       sprintf(generic, "ng%dn%d", instance, head_instance);
+       nvme_dev_full_path(n, devname, sizeof(devname));
+       nvme_generic_full_path(n, genname, sizeof(genname));
 
-       printf("%-12s %-12s %-8x %-26s %-16s ", nvme_ns_get_name(n),
-               generic, nvme_ns_get_nsid(n), usage, format);
+       printf("%-12s %-12s %-8x %-26s %-16s ", devname,
+               genname, nvme_ns_get_nsid(n), usage, format);
 }
 
 static void nvme_show_detailed_list(nvme_root_t r)
@@ -7178,13 +7222,16 @@ static void json_detail_list(nvme_root_t r)
 static struct json_object *json_list_item(nvme_ns_t n)
 {
        struct json_object *jdevice = json_create_object();
+       char devname[128] = { 0 };
 
        long long lba = nvme_ns_get_lba_size(n);
        double nsze = nvme_ns_get_lba_count(n) * lba;
        double nuse = nvme_ns_get_lba_util(n) * lba;
 
+       nvme_dev_full_path(n, devname, sizeof(devname));
+
        json_object_add_value_int(jdevice, "NameSpace", nvme_ns_get_nsid(n));
-       json_object_add_value_string(jdevice, "DevicePath", nvme_ns_get_name(n));
+       json_object_add_value_string(jdevice, "DevicePath", devname);
        json_object_add_value_string(jdevice, "Firmware", nvme_ns_get_firmware(n));
        json_object_add_value_string(jdevice, "ModelNumber", nvme_ns_get_model(n));
        json_object_add_value_string(jdevice, "SerialNumber", nvme_ns_get_serial(n));