diff options
| author | Kristen Carlson Accardi <kristen.c.accardi@intel.com> | 2007-05-23 13:57:38 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-05-23 20:14:11 -0700 |
| commit | 86ce18d7b7925bfd6b64c061828ca2a857ee83b8 (patch) | |
| tree | b753b7fd6d195aa7ed9eebc5a3917c5f20786260 | |
| parent | 352823160613b65fdaa558be486720a71f75ed86 (diff) | |
genhd: expose AN to user space
Allow user space to determine if a disk supports Asynchronous Notification of
media changes. This is done by adding a new sysfs file "capability_flags",
which is documented in (insert file name). This sysfs file will export all
disk capabilities flags to user space. We also define a new flag to define
the media change notification capability.
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | Documentation/block/capability.txt | 15 | ||||
| -rw-r--r-- | block/genhd.c | 10 | ||||
| -rw-r--r-- | include/linux/genhd.h | 1 |
3 files changed, 25 insertions, 1 deletions
diff --git a/Documentation/block/capability.txt b/Documentation/block/capability.txt new file mode 100644 index 00000000000..2f1729424ef --- /dev/null +++ b/Documentation/block/capability.txt @@ -0,0 +1,15 @@ +Generic Block Device Capability +=============================================================================== +This file documents the sysfs file block/<disk>/capability + +capability is a hex word indicating which capabilities a specific disk +supports. For more information on bits not listed here, see +include/linux/genhd.h + +Capability Value +------------------------------------------------------------------------------- +GENHD_FL_MEDIA_CHANGE_NOTIFY 4 + When this bit is set, the disk supports Asynchronous Notification + of media change events. These events will be broadcast to user + space via kernel uevent. + diff --git a/block/genhd.c b/block/genhd.c index 93a2cf65459..7efa8bb25da 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -423,7 +423,10 @@ static ssize_t disk_size_read(struct gendisk * disk, char *page) { return sprintf(page, "%llu\n", (unsigned long long)get_capacity(disk)); } - +static ssize_t disk_capability_read(struct gendisk *disk, char *page) +{ + return sprintf(page, "%x\n", disk->flags); +} static ssize_t disk_stats_read(struct gendisk * disk, char *page) { preempt_disable(); @@ -466,6 +469,10 @@ static struct disk_attribute disk_attr_size = { .attr = {.name = "size", .mode = S_IRUGO }, .show = disk_size_read }; +static struct disk_attribute disk_attr_capability = { + .attr = {.name = "capability", .mode = S_IRUGO }, + .show = disk_capability_read +}; static struct disk_attribute disk_attr_stat = { .attr = {.name = "stat", .mode = S_IRUGO }, .show = disk_stats_read @@ -506,6 +513,7 @@ static struct attribute * default_attrs[] = { &disk_attr_removable.attr, &disk_attr_size.attr, &disk_attr_stat.attr, + &disk_attr_capability.attr, #ifdef CONFIG_FAIL_MAKE_REQUEST &disk_attr_fail.attr, #endif diff --git a/include/linux/genhd.h b/include/linux/genhd.h index 4c03ee353e7..3fcfed2168a 100644 --- a/include/linux/genhd.h +++ b/include/linux/genhd.h @@ -94,6 +94,7 @@ struct hd_struct { #define GENHD_FL_REMOVABLE 1 #define GENHD_FL_DRIVERFS 2 +#define GENHD_FL_MEDIA_CHANGE_NOTIFY 4 #define GENHD_FL_CD 8 #define GENHD_FL_UP 16 #define GENHD_FL_SUPPRESS_PARTITION_INFO 32 |