block, partition: add partition_meta_info to hd_struct

I'm reposting this patch series as v4 since there have been no additional
comments, and I cleaned up one extra bit of unneeded code (in 3/3). The patches
are against Linus's tree: 2bfc96a127bc1cc94d26bfaa40159966064f9c8c
(2.6.36-rc3).

Would this patchset be suitable for inclusion in an mm branch?

This changes adds a partition_meta_info struct which itself contains a
union of structures that provide partition table specific metadata.

This change leaves the union empty. The subsequent patch includes an
implementation for CONFIG_EFI_PARTITION-based metadata.

Signed-off-by: Will Drewry <wad@chromium.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

diff --git a/block/genhd.c b/block/genhd.c
index 59a2db6..c8da120 100644 (file)
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -1004,6 +1004,7 @@ static void disk_release(struct device *dev)
        kfree(disk->random);
        disk_replace_part_tbl(disk, NULL);
        free_part_stats(&disk->part0);
+       free_part_info(&disk->part0);
        kfree(disk);
 }
 struct class block_class = {

diff --git a/block/ioctl.c b/block/ioctl.c
index d8052f0..2c15fe0 100644 (file)
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -62,7 +62,7 @@ static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user
 
                        /* all seems OK */
                        part = add_partition(disk, partno, start, length,
-                                            ADDPART_FLAG_NONE);
+                                            ADDPART_FLAG_NONE, NULL);
                        mutex_unlock(&bdev->bd_mutex);
                        return IS_ERR(part) ? PTR_ERR(part) : 0;
                case BLKPG_DEL_PARTITION:

diff --git a/fs/partitions/check.c b/fs/partitions/check.c
index 79fbf3f..6dfbee0 100644 (file)
--- a/fs/partitions/check.c
+++ b/fs/partitions/check.c
@@ -352,6 +352,7 @@ static void part_release(struct device *dev)
 {
        struct hd_struct *p = dev_to_part(dev);
        free_part_stats(p);
+       free_part_info(p);
        kfree(p);
 }
 
@@ -401,7 +402,8 @@ static DEVICE_ATTR(whole_disk, S_IRUSR | S_IRGRP | S_IROTH,
                   whole_disk_show, NULL);
 
 struct hd_struct *add_partition(struct gendisk *disk, int partno,
-                               sector_t start, sector_t len, int flags)
+                               sector_t start, sector_t len, int flags,
+                               struct partition_meta_info *info)
 {
        struct hd_struct *p;
        dev_t devt = MKDEV(0, 0);
@@ -438,6 +440,14 @@ struct hd_struct *add_partition(struct gendisk *disk, int partno,
        p->partno = partno;
        p->policy = get_disk_ro(disk);
 
+       if (info) {
+               struct partition_meta_info *pinfo = alloc_part_info(disk);
+               if (!pinfo)
+                       goto out_free_stats;
+               memcpy(pinfo, info, sizeof(*info));
+               p->info = pinfo;
+       }
+
        dname = dev_name(ddev);
        if (isdigit(dname[strlen(dname) - 1]))
                dev_set_name(pdev, "%sp%d", dname, partno);
@@ -451,7 +461,7 @@ struct hd_struct *add_partition(struct gendisk *disk, int partno,
 
        err = blk_alloc_devt(p, &devt);
        if (err)
-               goto out_free_stats;
+               goto out_free_info;
        pdev->devt = devt;
 
        /* delay uevent until 'holders' subdir is created */
@@ -481,6 +491,8 @@ struct hd_struct *add_partition(struct gendisk *disk, int partno,
 
        return p;
 
+out_free_info:
+       free_part_info(p);
 out_free_stats:
        free_part_stats(p);
 out_free:
@@ -642,6 +654,7 @@ rescan:
        /* add partitions */
        for (p = 1; p < state->limit; p++) {
                sector_t size, from;
+               struct partition_meta_info *info = NULL;
 
                size = state->parts[p].size;
                if (!size)
@@ -675,8 +688,12 @@ rescan:
                                size = get_capacity(disk) - from;
                        }
                }
+
+               if (state->parts[p].has_info)
+                       info = &state->parts[p].info;
                part = add_partition(disk, p, from, size,
-                                    state->parts[p].flags);
+                                    state->parts[p].flags,
+                                    &state->parts[p].info);
                if (IS_ERR(part)) {
                        printk(KERN_ERR " %s: p%d could not be added: %ld\n",
                               disk->disk_name, p, -PTR_ERR(part));

diff --git a/fs/partitions/check.h b/fs/partitions/check.h
index 8e4e103..d68bf4d 100644 (file)
--- a/fs/partitions/check.h
+++ b/fs/partitions/check.h
@@ -1,5 +1,6 @@
 #include <linux/pagemap.h>
 #include <linux/blkdev.h>
+#include <linux/genhd.h>
 
 /*
  * add_gd_partition adds a partitions details to the devices partition
@@ -12,6 +13,8 @@ struct parsed_partitions {
                sector_t from;
                sector_t size;
                int flags;
+               bool has_info;
+               struct partition_meta_info info;
        } parts[DISK_MAX_PARTS];
        int next;
        int limit;

diff --git a/include/linux/genhd.h b/include/linux/genhd.h
index 5f2f4c4..66e26b5 100644 (file)
--- a/include/linux/genhd.h
+++ b/include/linux/genhd.h
@@ -12,6 +12,7 @@
 #include <linux/types.h>
 #include <linux/kdev_t.h>
 #include <linux/rcupdate.h>
+#include <linux/slab.h>
 
 #ifdef CONFIG_BLOCK
 
@@ -86,7 +87,15 @@ struct disk_stats {
        unsigned long io_ticks;
        unsigned long time_in_queue;
 };
-       
+
+#define PARTITION_META_INFO_VOLNAMELTH 64
+#define PARTITION_META_INFO_UUIDLTH    16
+
+struct partition_meta_info {
+       u8 uuid[PARTITION_META_INFO_UUIDLTH];   /* always big endian */
+       u8 volname[PARTITION_META_INFO_VOLNAMELTH];
+};
+
 struct hd_struct {
        sector_t start_sect;
        sector_t nr_sects;
@@ -95,6 +104,7 @@ struct hd_struct {
        struct device __dev;
        struct kobject *holder_dir;
        int policy, partno;
+       struct partition_meta_info *info;
 #ifdef CONFIG_FAIL_MAKE_REQUEST
        int make_it_fail;
 #endif
@@ -181,6 +191,30 @@ static inline struct gendisk *part_to_disk(struct hd_struct *part)
        return NULL;
 }
 
+static inline void part_pack_uuid(const u8 *uuid_str, u8 *to)
+{
+       int i;
+       for (i = 0; i < 16; ++i) {
+               *to++ = (hex_to_bin(*uuid_str) << 4) |
+                       (hex_to_bin(*(uuid_str + 1)));
+               uuid_str += 2;
+               switch (i) {
+               case 3:
+               case 5:
+               case 7:
+               case 9:
+                       uuid_str++;
+                       continue;
+               }
+       }
+}
+
+static inline char *part_unpack_uuid(const u8 *uuid, char *out)
+{
+       sprintf(out, "%pU", uuid);
+       return out;
+}
+
 static inline int disk_max_parts(struct gendisk *disk)
 {
        if (disk->flags & GENHD_FL_EXT_DEVT)
@@ -342,6 +376,19 @@ static inline int part_in_flight(struct hd_struct *part)
        return part->in_flight[0] + part->in_flight[1];
 }
 
+static inline struct partition_meta_info *alloc_part_info(struct gendisk *disk)
+{
+       if (disk)
+               return kzalloc_node(sizeof(struct partition_meta_info),
+                                   GFP_KERNEL, disk->node_id);
+       return kzalloc(sizeof(struct partition_meta_info), GFP_KERNEL);
+}
+
+static inline void free_part_info(struct hd_struct *part)
+{
+       kfree(part->info);
+}
+
 /* block/blk-core.c */
 extern void part_round_stats(int cpu, struct hd_struct *part);
 
@@ -533,7 +580,9 @@ extern int disk_expand_part_tbl(struct gendisk *disk, int target);
 extern int rescan_partitions(struct gendisk *disk, struct block_device *bdev);
 extern struct hd_struct * __must_check add_partition(struct gendisk *disk,
                                                     int partno, sector_t start,
-                                                    sector_t len, int flags);
+                                                    sector_t len, int flags,
+                                                    struct partition_meta_info
+                                                      *info);
 extern void delete_partition(struct gendisk *, int);
 extern void printk_all_partitions(void);