[parted-devel] [PATCH] Add support for RAM drives

[Sebastian Parschauer]

Recognize RAM drives, so "parted -s /dev/ram0 p" now prints
"RAM Drive (brd)" instead of "Model: Unknown (unknown)".

In order for a device to be recognized as RAM drive, it has to
have major number 1. Also the BLKFLSBUF ioctl shouldn't be used
on RAM drives as it is used to zero the device.

* NEWS: Mention the change
* include/parted/device.h.in(PedDeviceType): Add PED_DEVICE_RAM.
* libparted/arch/linux.c(RAM_MAJOR): New define.
* libparted/arch/linux.c(_device_probe_type): Recognize RAM drives.
* libparted/arch/linux.c(linux_new): Handle RAM drives.
* libparted/arch/linux.c(_flush_cache): Skip RAM drives.
* parted/parted.c(do_print): Add "brd" to list of transports.

Signed-off-by: Sebastian Parschauer <sparschauer at suse.de>
---
 NEWS                       |  2 +-
 include/parted/device.in.h |  3 ++-
 libparted/arch/linux.c     | 12 ++++++++++--
 parted/parted.c            |  2 +-
 4 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/NEWS b/NEWS
index 198b35d..8e427d4 100644
--- a/NEWS
+++ b/NEWS
@@ -1,6 +1,6 @@
 GNU parted NEWS                                    -*- outline -*-
 
-  Parted now recognizes NVMe devices
+  Parted now recognizes NVMe devices and RAM drives
 
 * Noteworthy changes in release ?.? (????-??-??) [?]
 
diff --git a/include/parted/device.in.h b/include/parted/device.in.h
index d38db44..1b6e7b8 100644
--- a/include/parted/device.in.h
+++ b/include/parted/device.in.h
@@ -50,7 +50,8 @@ typedef enum {
         PED_DEVICE_AOE          = 16,
         PED_DEVICE_MD           = 17,
         PED_DEVICE_LOOP         = 18,
-        PED_DEVICE_NVME         = 19
+        PED_DEVICE_NVME         = 19,
+        PED_DEVICE_RAM          = 20
 } PedDeviceType;
 
 typedef struct _PedDevice PedDevice;
diff --git a/libparted/arch/linux.c b/libparted/arch/linux.c
index d87fe9c..9886d6e 100644
--- a/libparted/arch/linux.c
+++ b/libparted/arch/linux.c
@@ -279,6 +279,7 @@ struct blkdev_ioctl_param {
 #define LOOP_MAJOR              7
 #define MD_MAJOR                9
 #define BLKEXT_MAJOR            259
+#define RAM_MAJOR               1
 
 #define SCSI_BLK_MAJOR(M) (                                             \
                 (M) == SCSI_DISK0_MAJOR                                 \
@@ -701,6 +702,8 @@ _device_probe_type (PedDevice* dev)
                 dev->type = PED_DEVICE_MD;
         } else if (_is_blkext_major(dev_major) && dev->path && strstr(dev->path, "nvme")) {
                 dev->type = PED_DEVICE_NVME;
+        } else if (dev_major == RAM_MAJOR) {
+                dev->type = PED_DEVICE_RAM;
         } else {
                 dev->type = PED_DEVICE_UNKNOWN;
         }
@@ -1547,6 +1550,11 @@ linux_new (const char* path)
                         goto error_free_arch_specific;
                 break;
 
+        case PED_DEVICE_RAM:
+                if (!init_generic (dev, _("RAM Drive")))
+                        goto error_free_arch_specific;
+                break;
+
         default:
                 ped_exception_throw (PED_EXCEPTION_NO_FEATURE,
                                 PED_EXCEPTION_CANCEL,
@@ -1619,9 +1627,9 @@ _flush_cache (PedDevice* dev)
 {
         LinuxSpecific*  arch_specific = LINUX_SPECIFIC (dev);
         int             i;
-	int             lpn = _device_get_partition_range(dev);
+        int             lpn = _device_get_partition_range(dev);
 
-        if (dev->read_only)
+        if (dev->read_only || dev->type == PED_DEVICE_RAM)
                 return;
         dev->dirty = 0;
 
diff --git a/parted/parted.c b/parted/parted.c
index 7e6c266..80815e4 100644
--- a/parted/parted.c
+++ b/parted/parted.c
@@ -979,7 +979,7 @@ _print_disk_info (const PedDevice *dev, const PedDisk *diskp)
                                          "cpqarray", "file", "ataraid", "i2o",
                                          "ubd", "dasd", "viodasd", "sx8", "dm",
                                          "xvd", "sd/mmc", "virtblk", "aoe",
-                                         "md", "loopback", "nvme"};
+                                         "md", "loopback", "nvme", "brd"};
 
         char* start = ped_unit_format (dev, 0);
         PedUnit default_unit = ped_unit_get_default ();
-- 
2.6.6