X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Fcore%2Fcgroup.c;h=1327486509a6eaaf54af54119087f077f8429f42;hb=1683342af1fc85e75ba21264bbcedc26aef0fa39;hp=707ce470a123ba8a4d7f0a08e85ae93e69b18765;hpb=d4fdc205a4610965cee46408dbd046c922e7620c;p=elogind.git

diff --git a/src/core/cgroup.c b/src/core/cgroup.c
index 707ce470a..132748650 100644
--- a/src/core/cgroup.c
+++ b/src/core/cgroup.c
@@ -191,7 +191,84 @@ static int whitelist_device(const char *path, const char *node, const char *acc)
         return r;
 }
 
+static int whitelist_major(const char *path, const char *name, char type, const char *acc) {
+        _cleanup_fclose_ FILE *f = NULL;
+        char line[LINE_MAX];
+        bool good = false;
+        int r;
+
+        assert(path);
+        assert(acc);
+        assert(type == 'b' || type == 'c');
+
+        f = fopen("/proc/devices", "re");
+        if (!f) {
+                log_warning("Cannot open /proc/devices to resolve %s (%c): %m", name, type);
+                return -errno;
+        }
+
+        FOREACH_LINE(line, f, goto fail) {
+                char buf[2+DECIMAL_STR_MAX(unsigned)+3+4], *p, *w;
+                unsigned maj;
+
+                truncate_nl(line);
+
+                if (type == 'c' && streq(line, "Character devices:")) {
+                        good = true;
+                        continue;
+                }
+
+                if (type == 'b' && streq(line, "Block devices:")) {
+                        good = true;
+                        continue;
+                }
+
+                if (isempty(line)) {
+                        good = false;
+                        continue;
+                }
+
+                if (!good)
+                        continue;
+
+                p = strstrip(line);
+
+                w = strpbrk(p, WHITESPACE);
+                if (!w)
+                        continue;
+                *w = 0;
+
+                r = safe_atou(p, &maj);
+                if (r < 0)
+                        continue;
+                if (maj <= 0)
+                        continue;
+
+                w++;
+                w += strspn(w, WHITESPACE);
+                if (!streq(w, name))
+                        continue;
+
+                sprintf(buf,
+                        "%c %u:* %s",
+                        type,
+                        maj,
+                        acc);
+
+                r = cg_set_attribute("devices", path, "devices.allow", buf);
+                if (r < 0)
+                        log_warning("Failed to set devices.allow on %s: %s", path, strerror(-r));
+        }
+
+        return 0;
+
+fail:
+        log_warning("Failed to read /proc/devices: %m");
+        return -errno;
+}
+
 void cgroup_context_apply(CGroupContext *c, CGroupControllerMask mask, const char *path) {
+        bool is_root;
         int r;
 
         assert(c);
@@ -200,7 +277,11 @@ void cgroup_context_apply(CGroupContext *c, CGroupControllerMask mask, const cha
         if (mask == 0)
                 return;
 
-        if (mask & CGROUP_CPU) {
+        /* Some cgroup attributes are not support on the root cgroup,
+         * hence silently ignore */
+        is_root = isempty(path) || path_equal(path, "/");
+
+        if ((mask & CGROUP_CPU) && !is_root) {
                 char buf[DECIMAL_STR_MAX(unsigned long) + 1];
 
                 sprintf(buf, "%lu\n", c->cpu_shares);
@@ -216,23 +297,25 @@ void cgroup_context_apply(CGroupContext *c, CGroupControllerMask mask, const cha
                 CGroupBlockIODeviceWeight *w;
                 CGroupBlockIODeviceBandwidth *b;
 
-                sprintf(buf, "%lu\n", c->blockio_weight);
-                r = cg_set_attribute("blkio", path, "blkio.weight", buf);
-                if (r < 0)
-                        log_warning("Failed to set blkio.weight on %s: %s", path, strerror(-r));
+                if (!is_root) {
+                        sprintf(buf, "%lu\n", c->blockio_weight);
+                        r = cg_set_attribute("blkio", path, "blkio.weight", buf);
+                        if (r < 0)
+                                log_warning("Failed to set blkio.weight on %s: %s", path, strerror(-r));
 
-                /* FIXME: no way to reset this list */
-                LIST_FOREACH(device_weights, w, c->blockio_device_weights) {
-                        dev_t dev;
+                        /* FIXME: no way to reset this list */
+                        LIST_FOREACH(device_weights, w, c->blockio_device_weights) {
+                                dev_t dev;
 
-                        r = lookup_blkio_device(w->path, &dev);
-                        if (r < 0)
-                                continue;
+                                r = lookup_blkio_device(w->path, &dev);
+                                if (r < 0)
+                                        continue;
 
-                        sprintf(buf, "%u:%u %lu", major(dev), minor(dev), w->weight);
-                        r = cg_set_attribute("blkio", path, "blkio.weight_device", buf);
-                        if (r < 0)
-                                log_error("Failed to set blkio.weight_device on %s: %s", path, strerror(-r));
+                                sprintf(buf, "%u:%u %lu", major(dev), minor(dev), w->weight);
+                                r = cg_set_attribute("blkio", path, "blkio.weight_device", buf);
+                                if (r < 0)
+                                        log_error("Failed to set blkio.weight_device on %s: %s", path, strerror(-r));
+                        }
                 }
 
                 /* FIXME: no way to reset this list */
@@ -266,7 +349,7 @@ void cgroup_context_apply(CGroupContext *c, CGroupControllerMask mask, const cha
                         log_error("Failed to set memory.limit_in_bytes on %s: %s", path, strerror(-r));
         }
 
-        if (mask & CGROUP_DEVICE) {
+        if ((mask & CGROUP_DEVICE) && !is_root) {
                 CGroupDeviceAllow *a;
 
                 if (c->device_allow || c->device_policy != CGROUP_AUTO)
@@ -274,7 +357,7 @@ void cgroup_context_apply(CGroupContext *c, CGroupControllerMask mask, const cha
                 else
                         r = cg_set_attribute("devices", path, "devices.allow", "a");
                 if (r < 0)
-                        log_error("Failed to reset devices.list on %s: %s", path, strerror(-r));
+                        log_warning("Failed to reset devices.list on %s: %s", path, strerror(-r));
 
                 if (c->device_policy == CGROUP_CLOSED ||
                     (c->device_policy == CGROUP_AUTO && c->device_allow)) {
@@ -306,7 +389,15 @@ void cgroup_context_apply(CGroupContext *c, CGroupControllerMask mask, const cha
                                 continue;
 
                         acc[k++] = 0;
-                        whitelist_device(path, a->path, acc);
+
+                        if (startswith(a->path, "/dev/"))
+                                whitelist_device(path, a->path, acc);
+                        else if (startswith(a->path, "block-"))
+                                whitelist_major(path, a->path + 6, 'b', acc);
+                        else if (startswith(a->path, "char-"))
+                                whitelist_major(path, a->path + 5, 'c', acc);
+                        else
+                                log_debug("Ignoring device %s while writing cgroup attribute.", a->path);
                 }
         }
 }