--- rd.c.0 Thu Dec 23 08:13:58 1999
+++ rd.c Thu Dec 23 09:58:14 1999
@@ -58,6 +58,7 @@
#include <linux/fd.h>
#include <linux/module.h>
#include <linux/init.h>
+#include <linux/vmalloc.h>
#include <asm/system.h>
#include <asm/uaccess.h>
@@ -93,6 +94,7 @@
/* Various static variables go here. Most are used only in the RAM disk code.
*/
+static char *rd_memory[NUM_RAMDISKS]; /* where the data is kept */
static unsigned long rd_length[NUM_RAMDISKS]; /* Size of RAM disks in bytes */
static int rd_hardsec[NUM_RAMDISKS]; /* Size of real blocks in bytes */
static int rd_blocksizes[NUM_RAMDISKS]; /* Size of 1024 byte blocks :) */
@@ -210,17 +212,10 @@
goto repeat;
}
- /*
- * If we're reading, fill the buffer with 0's. This is okay since
- * we're using protected buffers which should never get freed...
- *
- * If we're writing, we protect the buffer.
- */
-
if (CURRENT->cmd == READ)
- memset(CURRENT->buffer, 0, len);
+ memcpy(CURRENT->buffer, rd_memory[minor] + offset, len);
else
- set_bit(BH_Protected, &CURRENT->bh->b_state);
+ memcpy(rd_memory[minor] + offset, CURRENT->buffer, len);
end_request(1);
goto repeat;
@@ -237,7 +232,8 @@
switch (cmd) {
case BLKFLSBUF:
- if (!capable(CAP_SYS_ADMIN)) return -EACCES;
+ if (!capable(CAP_SYS_ADMIN))
+ return -EACCES;
invalidate_buffers(inode->i_rdev);
break;
@@ -304,8 +300,10 @@
static int rd_open(struct inode * inode, struct file * filp)
{
+ int minor = DEVICE_NR(inode->i_rdev);
+
#ifdef CONFIG_BLK_DEV_INITRD
- if (DEVICE_NR(inode->i_rdev) == INITRD_MINOR) {
+ if (minor == INITRD_MINOR) {
if (!initrd_start) return -ENODEV;
initrd_users++;
filp->f_op = &initrd_fops;
@@ -313,11 +311,21 @@
}
#endif
- if (DEVICE_NR(inode->i_rdev) >= NUM_RAMDISKS)
+ if (minor >= NUM_RAMDISKS)
return -ENXIO;
- MOD_INC_USE_COUNT;
+ if (rd_memory[minor] == NULL) {
+ rd_memory[minor] = vmalloc(rd_length[minor]);
+ if (!rd_memory[minor]) {
+ printk(KERN_ERR
+ "RAMDISK: Can't vmalloc(%08lx) for minor=%d\n",
+ rd_length[minor], minor);
+ return -ENOMEM;
+ }
+ memset(rd_memory[minor], '\0', rd_length[minor]);
+ }
+ MOD_INC_USE_COUNT;
return 0;
}
@@ -346,9 +354,11 @@
{
int i;
- for (i = 0 ; i < NUM_RAMDISKS; i++)
+ for (i = 0; i < NUM_RAMDISKS; i++) {
+ if (rd_memory[i] != NULL)
+ vfree(rd_memory[i]);
invalidate_buffers(MKDEV(MAJOR_NR, i));
-
+ }
unregister_blkdev( MAJOR_NR, "ramdisk" );
blk_cleanup_queue(BLK_DEFAULT_QUEUE(MAJOR_NR));
}
@@ -356,16 +366,16 @@
/* This is the registration and initialization section of the RAM disk driver */
int __init rd_init (void)
{
- int i;
+ int i;
if (rd_blocksize > PAGE_SIZE || rd_blocksize < 512 ||
- (rd_blocksize & (rd_blocksize-1)))
- {
+ (rd_blocksize & (rd_blocksize-1))) {
printk("RAMDISK: wrong blocksize %d, reverting to defaults\n",
rd_blocksize);
rd_blocksize = BLOCK_SIZE;
}
+
if (register_blkdev(MAJOR_NR, "ramdisk", &fd_fops)) {
printk("RAMDISK: Could not get major %d", MAJOR_NR);
return -EIO;
@@ -375,10 +385,11 @@
for (i = 0; i < NUM_RAMDISKS; i++) {
/* rd_size is given in kB */
- rd_length[i] = rd_size << 10;
+ rd_length[i] = PAGE_ALIGN(rd_size << 10);
rd_hardsec[i] = rd_blocksize;
rd_blocksizes[i] = rd_blocksize;
rd_kbsize[i] = rd_size;
+ rd_memory[i] = NULL;
}
hardsect_size[MAJOR_NR] = rd_hardsec; /* Size of the RAM disk blocks */
