diff options
Diffstat (limited to 'Documentation/ramdisk.txt')
-rw-r--r-- | Documentation/ramdisk.txt | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/Documentation/ramdisk.txt b/Documentation/ramdisk.txt index 52f75b7d51c2..33e987df071e 100644 --- a/Documentation/ramdisk.txt +++ b/Documentation/ramdisk.txt | |||
@@ -22,16 +22,21 @@ The RAM disk dynamically grows as more space is required. It does this by using | |||
22 | RAM from the buffer cache. The driver marks the buffers it is using as dirty | 22 | RAM from the buffer cache. The driver marks the buffers it is using as dirty |
23 | so that the VM subsystem does not try to reclaim them later. | 23 | so that the VM subsystem does not try to reclaim them later. |
24 | 24 | ||
25 | Also, the RAM disk supports up to 16 RAM disks out of the box, and can | 25 | The RAM disk supports up to 16 RAM disks by default, and can be reconfigured |
26 | be reconfigured to support up to 255 RAM disks - change "#define NUM_RAMDISKS" | 26 | to support an unlimited number of RAM disks (at your own risk). Just change |
27 | in drivers/block/rd.c. To use RAM disk support with your system, run | 27 | the configuration symbol BLK_DEV_RAM_COUNT in the Block drivers config menu |
28 | './MAKEDEV ram' from the /dev directory. RAM disks are all major number 1, and | 28 | and (re)build the kernel. |
29 | start with minor number 0 for /dev/ram0, etc. If used, modern kernels use | 29 | |
30 | /dev/ram0 for an initrd. | 30 | To use RAM disk support with your system, run './MAKEDEV ram' from the /dev |
31 | directory. RAM disks are all major number 1, and start with minor number 0 | ||
32 | for /dev/ram0, etc. If used, modern kernels use /dev/ram0 for an initrd. | ||
31 | 33 | ||
32 | The old "ramdisk=<ram_size>" has been changed to "ramdisk_size=<ram_size>" to | 34 | The old "ramdisk=<ram_size>" has been changed to "ramdisk_size=<ram_size>" to |
33 | make it clearer. The original "ramdisk=<ram_size>" has been kept around for | 35 | make it clearer. The original "ramdisk=<ram_size>" has been kept around for |
34 | compatibility reasons, but it may be removed in the future. | 36 | compatibility reasons, but it may be removed in the future. |
37 | There are also config symbols (in the Block drivers config menu) for these | ||
38 | variables: BLK_DEV_RAM_SIZE defaults to 4096 and BLK_DEV_RAM_BLOCKSIZE | ||
39 | defaults to 1024. | ||
35 | 40 | ||
36 | The new RAM disk also has the ability to load compressed RAM disk images, | 41 | The new RAM disk also has the ability to load compressed RAM disk images, |
37 | allowing one to squeeze more programs onto an average installation or | 42 | allowing one to squeeze more programs onto an average installation or |