summaryrefslogtreecommitdiffstats
path: root/drivers/char/mem.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/char/mem.c')
-rw-r--r--drivers/char/mem.c68
1 files changed, 60 insertions, 8 deletions
diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index 947cb3c..4218738 100644
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -23,7 +23,10 @@
#include <linux/devfs_fs_kernel.h>
#include <linux/ptrace.h>
#include <linux/device.h>
+#include <linux/highmem.h>
+#include <linux/crash_dump.h>
#include <linux/backing-dev.h>
+#include <linux/bootmem.h>
#include <asm/uaccess.h>
#include <asm/io.h>
@@ -273,6 +276,40 @@ static int mmap_kmem(struct file * file, struct vm_area_struct * vma)
return mmap_mem(file, vma);
}
+#ifdef CONFIG_CRASH_DUMP
+/*
+ * Read memory corresponding to the old kernel.
+ */
+static ssize_t read_oldmem(struct file *file, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ unsigned long pfn, offset;
+ size_t read = 0, csize;
+ int rc = 0;
+
+ while (count) {
+ pfn = *ppos / PAGE_SIZE;
+ if (pfn > saved_max_pfn)
+ return read;
+
+ offset = (unsigned long)(*ppos % PAGE_SIZE);
+ if (count > PAGE_SIZE - offset)
+ csize = PAGE_SIZE - offset;
+ else
+ csize = count;
+
+ rc = copy_oldmem_page(pfn, buf, csize, offset, 1);
+ if (rc < 0)
+ return rc;
+ buf += csize;
+ *ppos += csize;
+ read += csize;
+ count -= csize;
+ }
+ return read;
+}
+#endif
+
extern long vread(char *buf, char *addr, unsigned long count);
extern long vwrite(char *buf, char *addr, unsigned long count);
@@ -484,7 +521,7 @@ static ssize_t write_kmem(struct file * file, const char __user * buf,
return virtr + wrote;
}
-#if defined(CONFIG_ISA) || !defined(__mc68000__)
+#if (defined(CONFIG_ISA) || !defined(__mc68000__)) && (!defined(CONFIG_PPC_ISERIES) || defined(CONFIG_PCI))
static ssize_t read_port(struct file * file, char __user * buf,
size_t count, loff_t *ppos)
{
@@ -721,6 +758,7 @@ static int open_port(struct inode * inode, struct file * filp)
#define read_full read_zero
#define open_mem open_port
#define open_kmem open_mem
+#define open_oldmem open_mem
static struct file_operations mem_fops = {
.llseek = memory_lseek,
@@ -744,7 +782,7 @@ static struct file_operations null_fops = {
.write = write_null,
};
-#if defined(CONFIG_ISA) || !defined(__mc68000__)
+#if (defined(CONFIG_ISA) || !defined(__mc68000__)) && (!defined(CONFIG_PPC_ISERIES) || defined(CONFIG_PCI))
static struct file_operations port_fops = {
.llseek = memory_lseek,
.read = read_port,
@@ -770,6 +808,13 @@ static struct file_operations full_fops = {
.write = write_full,
};
+#ifdef CONFIG_CRASH_DUMP
+static struct file_operations oldmem_fops = {
+ .read = read_oldmem,
+ .open = open_oldmem,
+};
+#endif
+
static ssize_t kmsg_write(struct file * file, const char __user * buf,
size_t count, loff_t *ppos)
{
@@ -804,7 +849,7 @@ static int memory_open(struct inode * inode, struct file * filp)
case 3:
filp->f_op = &null_fops;
break;
-#if defined(CONFIG_ISA) || !defined(__mc68000__)
+#if (defined(CONFIG_ISA) || !defined(__mc68000__)) && (!defined(CONFIG_PPC_ISERIES) || defined(CONFIG_PCI))
case 4:
filp->f_op = &port_fops;
break;
@@ -825,6 +870,11 @@ static int memory_open(struct inode * inode, struct file * filp)
case 11:
filp->f_op = &kmsg_fops;
break;
+#ifdef CONFIG_CRASH_DUMP
+ case 12:
+ filp->f_op = &oldmem_fops;
+ break;
+#endif
default:
return -ENXIO;
}
@@ -846,7 +896,7 @@ static const struct {
{1, "mem", S_IRUSR | S_IWUSR | S_IRGRP, &mem_fops},
{2, "kmem", S_IRUSR | S_IWUSR | S_IRGRP, &kmem_fops},
{3, "null", S_IRUGO | S_IWUGO, &null_fops},
-#if defined(CONFIG_ISA) || !defined(__mc68000__)
+#if (defined(CONFIG_ISA) || !defined(__mc68000__)) && (!defined(CONFIG_PPC_ISERIES) || defined(CONFIG_PCI))
{4, "port", S_IRUSR | S_IWUSR | S_IRGRP, &port_fops},
#endif
{5, "zero", S_IRUGO | S_IWUGO, &zero_fops},
@@ -854,9 +904,12 @@ static const struct {
{8, "random", S_IRUGO | S_IWUSR, &random_fops},
{9, "urandom", S_IRUGO | S_IWUSR, &urandom_fops},
{11,"kmsg", S_IRUGO | S_IWUSR, &kmsg_fops},
+#ifdef CONFIG_CRASH_DUMP
+ {12,"oldmem", S_IRUSR | S_IWUSR | S_IRGRP, &oldmem_fops},
+#endif
};
-static struct class_simple *mem_class;
+static struct class *mem_class;
static int __init chr_dev_init(void)
{
@@ -865,10 +918,9 @@ static int __init chr_dev_init(void)
if (register_chrdev(MEM_MAJOR,"mem",&memory_fops))
printk("unable to get major %d for memory devs\n", MEM_MAJOR);
- mem_class = class_simple_create(THIS_MODULE, "mem");
+ mem_class = class_create(THIS_MODULE, "mem");
for (i = 0; i < ARRAY_SIZE(devlist); i++) {
- class_simple_device_add(mem_class,
- MKDEV(MEM_MAJOR, devlist[i].minor),
+ class_device_create(mem_class, MKDEV(MEM_MAJOR, devlist[i].minor),
NULL, devlist[i].name);
devfs_mk_cdev(MKDEV(MEM_MAJOR, devlist[i].minor),
S_IFCHR | devlist[i].mode, devlist[i].name);
OpenPOWER on IntegriCloud