[PATCH v7 5/7] xl: support naming of assignable devices

[Paul Durrant <paul@xen.org>]

From: Paul Durrant <pdurrant@amazon.com>

With this patch applied 'xl pci-assignable-add' will take an optional '--name'
parameter, 'xl pci-assignable-remove' can be passed either a BDF or a name and
'xl pci-assignable-list' will take a optional '--show-names' flag which
determines whether names are displayed in its output.

Signed-off-by: Paul Durrant <pdurrant@amazon.com>
---
Cc: Ian Jackson <iwj@xenproject.org>
Cc: Wei Liu <wl@xen.org>
Cc: Anthony PERARD <anthony.perard@citrix.com>

v7:
 - Heavily re-worked, bearing only some resemblance to similarly named v6 patch
---
 tools/xl/xl_cmdtable.c | 12 ++++---
 tools/xl/xl_pci.c      | 89 ++++++++++++++++++++++++++++++++++++--------------
 2 files changed, 73 insertions(+), 28 deletions(-)

diff --git a/tools/xl/xl_cmdtable.c b/tools/xl/xl_cmdtable.c
index 30e17a2848..bd8af12ff3 100644
--- a/tools/xl/xl_cmdtable.c
+++ b/tools/xl/xl_cmdtable.c
@@ -105,21 +105,25 @@ struct cmd_spec cmd_table[] = {
     { "pci-assignable-add",
       &main_pciassignable_add, 0, 1,
       "Make a device assignable for pci-passthru",
-      "<BDF>",
+      "[options] <BDF>",
+      "-n NAME, --name=NAME    Name the assignable device.\n"
       "-h                      Print this help.\n"
     },
     { "pci-assignable-remove",
       &main_pciassignable_remove, 0, 1,
       "Remove a device from being assignable",
-      "[options] <BDF>",
+      "[options] <BDF>|NAME",
       "-h                      Print this help.\n"
       "-r                      Attempt to re-assign the device to the\n"
-      "                        original driver"
+      "                        original driver."
     },
     { "pci-assignable-list",
       &main_pciassignable_list, 0, 0,
       "List all the assignable pci devices",
-      "",
+      "[options]",
+      "-h                      Print this help.\n"
+      "-n, --show-names        Display assignable device names where\n"
+      "                        supplied.\n"
     },
     { "pause",
       &main_pause, 0, 1,
diff --git a/tools/xl/xl_pci.c b/tools/xl/xl_pci.c
index 9a66494bb5..b1c3ae2a72 100644
--- a/tools/xl/xl_pci.c
+++ b/tools/xl/xl_pci.c
@@ -151,7 +151,7 @@ int main_pciattach(int argc, char **argv)
     return EXIT_SUCCESS;
 }
 
-static void pciassignable_list(void)
+static void pciassignable_list(bool show_names)
 {
     libxl_device_pci *pcis;
     int num, i;
@@ -161,8 +161,12 @@ static void pciassignable_list(void)
     if ( pcis == NULL )
         return;
     for (i = 0; i < num; i++) {
-        printf("%04x:%02x:%02x.%01x\n",
-               pcis[i].domain, pcis[i].bus, pcis[i].dev, pcis[i].func);
+        libxl_device_pci *pci = &pcis[i];
+        char *name = show_names ? pci->name : NULL;
+
+        printf("%04x:%02x:%02x.%01x %s\n",
+               pci->domain, pci->bus, pci->dev, pci->func,
+               name ?: "");
     }
     libxl_device_pci_assignable_list_free(pcis, num);
 }
@@ -170,20 +174,27 @@ static void pciassignable_list(void)
 int main_pciassignable_list(int argc, char **argv)
 {
     int opt;
-
-    SWITCH_FOREACH_OPT(opt, "", NULL, "pci-assignable-list", 0) {
-        /* No options */
+    static struct option opts[] = {
+        {"show-names", 0, 0, 'n'},
+        COMMON_LONG_OPTS
+    };
+    bool show_names = false;
+
+    SWITCH_FOREACH_OPT(opt, "n", opts, "pci-assignable-list", 0) {
+    case 'n':
+        show_names = true;
+        break;
     }
 
-    pciassignable_list();
+    pciassignable_list(show_names);
     return 0;
 }
 
-static int pciassignable_add(const char *bdf, int rebind)
+static int pciassignable_add(const char *bdf, const char *name, int rebind)
 {
     libxl_device_pci pci;
     XLU_Config *config;
-    int r = 0;
+    int r;
 
     libxl_device_pci_init(&pci);
 
@@ -195,8 +206,15 @@ static int pciassignable_add(const char *bdf, int rebind)
         exit(2);
     }
 
-    if (libxl_device_pci_assignable_add(ctx, &pci, rebind))
-        r = 1;
+    if (name) {
+        pci.name = strdup(name);
+        if (!pci.name) {
+            fprintf(stderr, "pci-assignable-add: memory allocation failure\n");
+            exit(2);
+        }
+    }
+
+    r = libxl_device_pci_assignable_add(ctx, &pci, rebind);
 
     libxl_device_pci_dispose(&pci);
     xlu_cfg_destroy(config);
@@ -208,38 +226,61 @@ int main_pciassignable_add(int argc, char **argv)
 {
     int opt;
     const char *bdf = NULL;
-
-    SWITCH_FOREACH_OPT(opt, "", NULL, "pci-assignable-add", 1) {
-        /* No options */
+    static struct option opts[] = {
+        {"name", 1, 0, 'n'},
+        COMMON_LONG_OPTS
+    };
+    const char *name = NULL;
+
+    SWITCH_FOREACH_OPT(opt, "n:", opts, "pci-assignable-add", 1) {
+    case 'n':
+        name = optarg;
+        break;
     }
 
     bdf = argv[optind];
 
-    if (pciassignable_add(bdf, 1))
+    if (pciassignable_add(bdf, name, 1))
         return EXIT_FAILURE;
 
     return EXIT_SUCCESS;
 }
 
-static int pciassignable_remove(const char *bdf, int rebind)
+static int pciassignable_remove(const char *ident, int rebind)
 {
     libxl_device_pci pci;
     XLU_Config *config;
-    int r = 0;
+    int r;
 
     libxl_device_pci_init(&pci);
 
     config = xlu_cfg_init(stderr, "command line");
     if (!config) { perror("xlu_cfg_init"); exit(-1); }
 
-    if (xlu_pci_parse_bdf(config, &pci, bdf)) {
-        fprintf(stderr, "pci-assignable-remove: malformed BDF \"%s\"\n", bdf);
+    /* Try remove-by-name first */
+    pci.name = strdup(ident);
+    if (!pci.name) {
+        fprintf(stderr, "pci-assignable-add: memory allocation failure\n");
         exit(2);
     }
 
-    if (libxl_device_pci_assignable_remove(ctx, &pci, rebind))
-        r = 1;
+    r = libxl_device_pci_assignable_remove(ctx, &pci, rebind);
+    if (!r || r != ERROR_NOTFOUND)
+        goto out;
+
+    /* If remove-by-name failed to find the device, try remove-by-BDF */
+    free(pci.name);
+    pci.name = NULL;
 
+    if (xlu_pci_parse_bdf(config, &pci, ident)) {
+        fprintf(stderr,
+                "pci-assignable-remove: malformed BDF '%s'\n", ident);
+        exit(2);
+    }
+
+    r = libxl_device_pci_assignable_remove(ctx, &pci, rebind);
+
+out:
     libxl_device_pci_dispose(&pci);
     xlu_cfg_destroy(config);
 
@@ -249,7 +290,7 @@ static int pciassignable_remove(const char *bdf, int rebind)
 int main_pciassignable_remove(int argc, char **argv)
 {
     int opt;
-    const char *bdf = NULL;
+    const char *ident = NULL;
     int rebind = 0;
 
     SWITCH_FOREACH_OPT(opt, "r", NULL, "pci-assignable-remove", 1) {
@@ -258,9 +299,9 @@ int main_pciassignable_remove(int argc, char **argv)
         break;
     }
 
-    bdf = argv[optind];
+    ident = argv[optind];
 
-    if (pciassignable_remove(bdf, rebind))
+    if (pciassignable_remove(ident, rebind))
         return EXIT_FAILURE;
 
     return EXIT_SUCCESS;
-- 
2.11.0