6 files changed, 141 insertions, 29 deletions

diff --git a/Documentation/ABI/testing/sysfs-firmware-dmi b/Documentation/ABI/testing/sysfs-firmware-dmi-entries
index c78f9ab01e56..210ad44b95a5 100644
--- a/Documentation/ABI/testing/sysfs-firmware-dmi
+++ b/Documentation/ABI/testing/sysfs-firmware-dmi-entries
@@ -1,4 +1,4 @@
-What:           /sys/firmware/dmi/
+What:           /sys/firmware/dmi/entries/
 Date:           February 2011
 Contact:        Mike Waychison <mikew@google.com>
 Description:
diff --git a/Documentation/ABI/testing/sysfs-firmware-dmi-tables b/Documentation/ABI/testing/sysfs-firmware-dmi-tables
new file mode 100644
index 000000000000..ff3cac8ed0bd
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-firmware-dmi-tables
@@ -0,0 +1,22 @@
+What:           /sys/firmware/dmi/tables/
+Date:           April 2015
+Contact:        Ivan Khoronzhuk <ivan.khoronzhuk@globallogic.com>
+Description:
+                The firmware provides DMI structures as a packed list of
+                data referenced by a SMBIOS table entry point. The SMBIOS
+                entry point contains general information, like SMBIOS
+                version, DMI table size, etc. The structure, content and
+                size of SMBIOS entry point is dependent on SMBIOS version.
+                The format of SMBIOS entry point and DMI structures
+                can be read in SMBIOS specification.
+
+                The dmi/tables provides raw SMBIOS entry point and DMI tables
+                through sysfs as an alternative to utilities reading them
+                from /dev/mem. The raw SMBIOS entry point and DMI table are
+                presented as binary attributes and are accessible via:
+
+                /sys/firmware/dmi/tables/smbios_entry_point
+                /sys/firmware/dmi/tables/DMI
+
+                The complete DMI information can be obtained using these two
+                tables.
diff --git a/MAINTAINERS b/MAINTAINERS
index 73cfd4b0f539..25916c00d7a3 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3337,6 +3337,8 @@ F:	drivers/hwmon/dme1737.c
 DMI/SMBIOS SUPPORT
 M:      Jean Delvare <jdelvare@suse.de>
 S:      Maintained
+T:      quilt http://jdelvare.nerim.net/devel/linux/jdelvare-dmi/
+F:      Documentation/ABI/testing/sysfs-firmware-dmi-tables
 F:      drivers/firmware/dmi-id.c
 F:      drivers/firmware/dmi_scan.c
 F:      include/linux/dmi.h
diff --git a/drivers/firmware/dmi-sysfs.c b/drivers/firmware/dmi-sysfs.c
index e0f1cb3d3598..ef76e5eecf0b 100644
--- a/drivers/firmware/dmi-sysfs.c
+++ b/drivers/firmware/dmi-sysfs.c
@@ -566,7 +566,6 @@ static struct kobj_type dmi_sysfs_entry_ktype = {
         .default_attrs = dmi_sysfs_entry_attrs,
 };
 
-static struct kobject *dmi_kobj;
 static struct kset *dmi_kset;
 
 /* Global count of all instances seen.  Only for setup */
@@ -648,17 +647,20 @@ static void cleanup_entry_list(void)
 
 static int __init dmi_sysfs_init(void)
 {
-        int error = -ENOMEM;
+        int error;
         int val;
 
-        /* Set up our directory */
-        dmi_kobj = kobject_create_and_add("dmi", firmware_kobj);
-        if (!dmi_kobj)
+        if (!dmi_kobj) {
+                pr_err("dmi-sysfs: dmi entry is absent.\n");
+                error = -ENODATA;
                 goto err;
+        }
 
         dmi_kset = kset_create_and_add("entries", NULL, dmi_kobj);
-        if (!dmi_kset)
+        if (!dmi_kset) {
+                error = -ENOMEM;
                 goto err;
+        }
 
         val = 0;
         error = dmi_walk(dmi_sysfs_register_handle, &val);
@@ -675,7 +677,6 @@ static int __init dmi_sysfs_init(void)
 err:
         cleanup_entry_list();
         kset_unregister(dmi_kset);
-        kobject_put(dmi_kobj);
         return error;
 }
 
@@ -685,8 +686,6 @@ static void __exit dmi_sysfs_exit(void)
         pr_debug("dmi-sysfs: unloading.\n");
         cleanup_entry_list();
         kset_unregister(dmi_kset);
-        kobject_del(dmi_kobj);
-        kobject_put(dmi_kobj);
 }
 
 module_init(dmi_sysfs_init);
diff --git a/drivers/firmware/dmi_scan.c b/drivers/firmware/dmi_scan.c
index 97b1616aa391..ac1ce4a73edf 100644
--- a/drivers/firmware/dmi_scan.c
+++ b/drivers/firmware/dmi_scan.c
@@ -10,6 +10,9 @@
 #include <asm/dmi.h>
 #include <asm/unaligned.h>
 
+struct kobject *dmi_kobj;
+EXPORT_SYMBOL_GPL(dmi_kobj);
+
 /*
  * DMI stands for "Desktop Management Interface".  It is part
  * of and an antecedent to, SMBIOS, which stands for System
@@ -20,6 +23,9 @@ static const char dmi_empty_string[] = "        ";
 static u32 dmi_ver __initdata;
 static u32 dmi_len;
 static u16 dmi_num;
+static u8 smbios_entry_point[32];
+static int smbios_entry_point_size;
+
 /*
  * Catch too early calls to dmi_check_system():
  */
@@ -80,18 +86,18 @@ static const char * __init dmi_string(const struct dmi_header *dm, u8 s)
  *      We have to be cautious here. We have seen BIOSes with DMI pointers
  *      pointing to completely the wrong place for example
  */
-static void dmi_table(u8 *buf,
-                      void (*decode)(const struct dmi_header *, void *),
-                      void *private_data)
+static void dmi_decode_table(u8 *buf,
+                             void (*decode)(const struct dmi_header *, void *),
+                             void *private_data)
 {
         u8 *data = buf;
         int i = 0;
 
         /*
          * Stop when we have seen all the items the table claimed to have
-         * (SMBIOS < 3.0 only) OR we reach an end-of-table marker OR we run
-         * off the end of the table (should never happen but sometimes does
-         * on bogus implementations.)
+         * (SMBIOS < 3.0 only) OR we reach an end-of-table marker (SMBIOS
+         * >= 3.0 only) OR we run off the end of the table (should never
+         * happen but sometimes does on bogus implementations.)
          */
         while ((!dmi_num || i < dmi_num) &&
                (data - buf + sizeof(struct dmi_header)) <= dmi_len) {
@@ -108,15 +114,24 @@ static void dmi_table(u8 *buf,
                 if (data - buf < dmi_len - 1)
                         decode(dm, private_data);
 
+                data += 2;
+                i++;
+
                 /*
                  * 7.45 End-of-Table (Type 127) [SMBIOS reference spec v3.0.0]
+                 * For tables behind a 64-bit entry point, we have no item
+                 * count and no exact table length, so stop on end-of-table
+                 * marker. For tables behind a 32-bit entry point, we have
+                 * seen OEM structures behind the end-of-table marker on
+                 * some systems, so don't trust it.
                  */
-                if (dm->type == DMI_ENTRY_END_OF_TABLE)
+                if (!dmi_num && dm->type == DMI_ENTRY_END_OF_TABLE)
                         break;
-
-                data += 2;
-                i++;
         }
+
+        /* Trim DMI table length if needed */
+        if (dmi_len > data - buf)
+                dmi_len = data - buf;
 }
 
 static phys_addr_t dmi_base;
@@ -125,16 +140,17 @@ static int __init dmi_walk_early(void (*decode)(const struct dmi_header *,
                 void *))
 {
         u8 *buf;
+        u32 orig_dmi_len = dmi_len;
 
-        buf = dmi_early_remap(dmi_base, dmi_len);
+        buf = dmi_early_remap(dmi_base, orig_dmi_len);
         if (buf == NULL)
                 return -1;
 
-        dmi_table(buf, decode, NULL);
+        dmi_decode_table(buf, decode, NULL);
 
         add_device_randomness(buf, dmi_len);
 
-        dmi_early_unmap(buf, dmi_len);
+        dmi_early_unmap(buf, orig_dmi_len);
         return 0;
 }
 
@@ -478,17 +494,19 @@ static int __init dmi_present(const u8 *buf)
         if (memcmp(buf, "_SM_", 4) == 0 &&
             buf[5] < 32 && dmi_checksum(buf, buf[5])) {
                 smbios_ver = get_unaligned_be16(buf + 6);
+                smbios_entry_point_size = buf[5];
+                memcpy(smbios_entry_point, buf, smbios_entry_point_size);
 
                 /* Some BIOS report weird SMBIOS version, fix that up */
                 switch (smbios_ver) {
                 case 0x021F:
                 case 0x0221:
-                        pr_debug("SMBIOS version fixup(2.%d->2.%d)\n",
+                        pr_debug("SMBIOS version fixup (2.%d->2.%d)\n",
                                  smbios_ver & 0xFF, 3);
                         smbios_ver = 0x0203;
                         break;
                 case 0x0233:
-                        pr_debug("SMBIOS version fixup(2.%d->2.%d)\n", 51, 6);
+                        pr_debug("SMBIOS version fixup (2.%d->2.%d)\n", 51, 6);
                         smbios_ver = 0x0206;
                         break;
                 }
@@ -512,6 +530,9 @@ static int __init dmi_present(const u8 *buf)
                                 pr_info("SMBIOS %d.%d present.\n",
                                        dmi_ver >> 8, dmi_ver & 0xFF);
                         } else {
+                                smbios_entry_point_size = 15;
+                                memcpy(smbios_entry_point, buf,
+                                       smbios_entry_point_size);
                                 pr_info("Legacy DMI %d.%d present.\n",
                                        dmi_ver >> 8, dmi_ver & 0xFF);
                         }
@@ -533,11 +554,12 @@ static int __init dmi_smbios3_present(const u8 *buf)
 {
         if (memcmp(buf, "_SM3_", 5) == 0 &&
             buf[6] < 32 && dmi_checksum(buf, buf[6])) {
-                dmi_ver = get_unaligned_be32(buf + 6);
-                dmi_ver &= 0xFFFFFF;
+                dmi_ver = get_unaligned_be32(buf + 6) & 0xFFFFFF;
                 dmi_num = 0;                    /* No longer specified */
                 dmi_len = get_unaligned_le32(buf + 12);
                 dmi_base = get_unaligned_le64(buf + 16);
+                smbios_entry_point_size = buf[6];
+                memcpy(smbios_entry_point, buf, smbios_entry_point_size);
 
                 if (dmi_walk_early(dmi_decode) == 0) {
                         pr_info("SMBIOS %d.%d.%d present.\n",
@@ -629,6 +651,71 @@ void __init dmi_scan_machine(void)
         dmi_initialized = 1;
 }
 
+static ssize_t raw_table_read(struct file *file, struct kobject *kobj,
+                              struct bin_attribute *attr, char *buf,
+                              loff_t pos, size_t count)
+{
+        memcpy(buf, attr->private + pos, count);
+        return count;
+}
+
+static BIN_ATTR(smbios_entry_point, S_IRUSR, raw_table_read, NULL, 0);
+static BIN_ATTR(DMI, S_IRUSR, raw_table_read, NULL, 0);
+
+static int __init dmi_init(void)
+{
+        struct kobject *tables_kobj;
+        u8 *dmi_table;
+        int ret = -ENOMEM;
+
+        if (!dmi_available) {
+                ret = -ENODATA;
+                goto err;
+        }
+
+        /*
+         * Set up dmi directory at /sys/firmware/dmi. This entry should stay
+         * even after farther error, as it can be used by other modules like
+         * dmi-sysfs.
+         */
+        dmi_kobj = kobject_create_and_add("dmi", firmware_kobj);
+        if (!dmi_kobj)
+                goto err;
+
+        tables_kobj = kobject_create_and_add("tables", dmi_kobj);
+        if (!tables_kobj)
+                goto err;
+
+        dmi_table = dmi_remap(dmi_base, dmi_len);
+        if (!dmi_table)
+                goto err_tables;
+
+        bin_attr_smbios_entry_point.size = smbios_entry_point_size;
+        bin_attr_smbios_entry_point.private = smbios_entry_point;
+        ret = sysfs_create_bin_file(tables_kobj, &bin_attr_smbios_entry_point);
+        if (ret)
+                goto err_unmap;
+
+        bin_attr_DMI.size = dmi_len;
+        bin_attr_DMI.private = dmi_table;
+        ret = sysfs_create_bin_file(tables_kobj, &bin_attr_DMI);
+        if (!ret)
+                return 0;
+
+        sysfs_remove_bin_file(tables_kobj,
+                              &bin_attr_smbios_entry_point);
+ err_unmap:
+        dmi_unmap(dmi_table);
+ err_tables:
+        kobject_del(tables_kobj);
+        kobject_put(tables_kobj);
+ err:
+        pr_err("dmi: Firmware registration failed.\n");
+
+        return ret;
+}
+subsys_initcall(dmi_init);
+
 /**
  * dmi_set_dump_stack_arch_desc - set arch description for dump_stack()
  *
@@ -897,7 +984,7 @@ int dmi_walk(void (*decode)(const struct dmi_header *, void *),
         if (buf == NULL)
                 return -1;
 
-        dmi_table(buf, decode, private_data);
+        dmi_decode_table(buf, decode, private_data);
 
         dmi_unmap(buf);
         return 0;
diff --git a/include/linux/dmi.h b/include/linux/dmi.h
index f820f0a336c9..5055ac34142d 100644
--- a/include/linux/dmi.h
+++ b/include/linux/dmi.h
@@ -2,6 +2,7 @@
 #define __DMI_H__
 
 #include <linux/list.h>
+#include <linux/kobject.h>
 #include <linux/mod_devicetable.h>
 
 /* enum dmi_field is in mod_devicetable.h */
@@ -74,7 +75,7 @@ struct dmi_header {
         u8 type;
         u8 length;
         u16 handle;
-};
+} __packed;
 
 struct dmi_device {
         struct list_head list;
@@ -93,6 +94,7 @@ struct dmi_dev_onboard {
         int devfn;
 };
 
+extern struct kobject *dmi_kobj;
 extern int dmi_check_system(const struct dmi_system_id *list);
 const struct dmi_system_id *dmi_first_match(const struct dmi_system_id *list);
 extern const char * dmi_get_system_info(int field);