fs(procfs): add /proc/cpuinfo

mosmeh · Jul 5, 2024 · 6a3eac8 · 6a3eac8
1 parent c4ff122
commit 6a3eac8
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Showing 2 changed files with 55 additions and 0 deletions.
diff --git a/kernel/fs/procfs/procfs.c b/kernel/fs/procfs/procfs.c
@@ -17,6 +17,7 @@ static int procfs_item_open(file_description* desc, mode_t mode) {
     procfs_item_inode* node = (procfs_item_inode*)desc->inode;
     int rc = node->populate(desc, vec);
     if (IS_ERR(rc)) {
+        vec_destroy(vec);
         kfree(vec);
         return rc;
     }

diff --git a/kernel/fs/procfs/root.c b/kernel/fs/procfs/root.c
@@ -3,6 +3,7 @@
 #include <common/stdlib.h>
 #include <kernel/api/dirent.h>
 #include <kernel/api/sys/sysmacros.h>
+#include <kernel/cpu.h>
 #include <kernel/fs/dentry.h>
 #include <kernel/interrupts.h>
 #include <kernel/kmsg.h>
@@ -18,6 +19,58 @@ static int populate_cmdline(file_description* desc, struct vec* vec) {
     return vec_printf(vec, "%s\n", cmdline_get_raw());
 }
 
+static int print_flag(struct vec* vec, int feature, const char* name) {
+    if (!name[0]) {
+        // Skip empty names
+        return 0;
+    }
+    if (!cpu_has_feature(feature))
+        return 0;
+    return vec_printf(vec, "%s ", name);
+}
+
+static int populate_cpuinfo(file_description* desc, struct vec* vec) {
+    (void)desc;
+    struct cpu* cpu = cpu_get();
+
+    int ret =
+        vec_printf(vec,
+                   "vendor_id       : %s\n"
+                   "cpu family      : %u\n"
+                   "model           : %u\n"
+                   "model name      : %s\n",
+                   cpu->vendor_id, cpu->family, cpu->model, cpu->model_name);
+    if (IS_ERR(ret))
+        return ret;
+
+    if (cpu->stepping) {
+        ret = vec_printf(vec, "stepping        : %u\n", cpu->stepping);
+        if (IS_ERR(ret))
+            return ret;
+    }
+
+    const char* fpu = cpu_has_feature(X86_FEATURE_FPU) ? "yes" : "no";
+    ret = vec_printf(vec,
+                     "fpu             : %s\n"
+                     "fpu_exception   : %s\n"
+                     "wp              : yes\n"
+                     "flags           : ",
+                     fpu, fpu);
+    if (IS_ERR(ret))
+        return ret;
+
+#define F(variant, name)                                                       \
+    ret = print_flag(vec, X86_FEATURE_##variant, #name);                       \
+    if (IS_ERR(ret))                                                           \
+        return ret;
+    ENUMERATE_X86_FEATURES(F)
+#undef F
+
+    return vec_printf(vec,
+                      "\naddress sizes   : %u bits physical, %u bits virtual\n",
+                      cpu->phys_addr_bits, cpu->virt_addr_bits);
+}
+
 static int populate_kallsyms(file_description* desc, struct vec* vec) {
     (void)desc;
     const struct symbol* symbol = NULL;
@@ -87,6 +140,7 @@ static int populate_version(file_description* desc, struct vec* vec) {
 }
 
 static procfs_item_def root_items[] = {
+    {"cpuinfo", S_IFREG, populate_cpuinfo},
     {"cmdline", S_IFREG, populate_cmdline},
     {"kallsyms", S_IFREG, populate_kallsyms},
     {"kmsg", S_IFREG, populate_kmsg},