Import of Linus's Linux 1.1.68

1 files changed, 388 insertions, 0 deletions

diff --git a/drivers/char/mem.c b/drivers/char/mem.c
new file mode 100644
index 000000000..4e721da79
--- /dev/null
+++ b/drivers/char/mem.c
@@ -0,0 +1,388 @@
+/*
+ *  linux/drivers/char/mem.c
+ *
+ *  Copyright (C) 1991, 1992  Linus Torvalds
+ */
+
+#include <linux/config.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/major.h>
+#include <linux/tty.h>
+#include <linux/mouse.h>
+#include <linux/tpqic02.h>
+#include <linux/malloc.h>
+#include <linux/mman.h>
+
+#include <asm/segment.h>
+#include <asm/io.h>
+
+#ifdef CONFIG_SOUND
+extern long soundcard_init(long mem_start);
+#endif
+
+static int read_ram(struct inode * inode, struct file * file,char * buf, int count)
+{
+	return -EIO;
+}
+
+static int write_ram(struct inode * inode, struct file * file,char * buf, int count)
+{
+	return -EIO;
+}
+
+static int read_mem(struct inode * inode, struct file * file,char * buf, int count)
+{
+	unsigned long p = file->f_pos;
+	int read;
+
+	if (count < 0)
+		return -EINVAL;
+	if (p >= high_memory)
+		return 0;
+	if (count > high_memory - p)
+		count = high_memory - p;
+	read = 0;
+	while (p < PAGE_SIZE && count > 0) {
+		put_fs_byte(0,buf);
+		buf++;
+		p++;
+		count--;
+		read++;
+	}
+	memcpy_tofs(buf,(void *) p,count);
+	read += count;
+	file->f_pos += read;
+	return read;
+}
+
+static int write_mem(struct inode * inode, struct file * file,char * buf, int count)
+{
+	unsigned long p = file->f_pos;
+	int written;
+
+	if (count < 0)
+		return -EINVAL;
+	if (p >= high_memory)
+		return 0;
+	if (count > high_memory - p)
+		count = high_memory - p;
+	written = 0;
+	while (p < PAGE_SIZE && count > 0) {
+		/* Hmm. Do something? */
+		buf++;
+		p++;
+		count--;
+		written++;
+	}
+	memcpy_fromfs((void *) p,buf,count);
+	written += count;
+	file->f_pos += written;
+	return count;
+}
+
+static int mmap_mem(struct inode * inode, struct file * file, struct vm_area_struct * vma)
+{
+	if (vma->vm_offset & ~PAGE_MASK)
+		return -ENXIO;
+	if (x86 > 3 && vma->vm_offset >= high_memory)
+		vma->vm_page_prot |= PAGE_PCD;
+	if (remap_page_range(vma->vm_start, vma->vm_offset, vma->vm_end - vma->vm_start, vma->vm_page_prot))
+		return -EAGAIN;
+	vma->vm_inode = inode;
+	inode->i_count++;
+	return 0;
+}
+
+static int read_kmem(struct inode *inode, struct file *file, char *buf, int count)
+{
+	int read1, read2;
+
+	read1 = read_mem(inode, file, buf, count);
+	if (read1 < 0)
+		return read1;
+	read2 = vread(buf + read1, (char *) ((unsigned long) file->f_pos), count - read1);
+	if (read2 < 0)
+		return read2;
+	file->f_pos += read2;
+	return read1 + read2;
+}
+
+static int read_port(struct inode * inode,struct file * file,char * buf, int count)
+{
+	unsigned int i = file->f_pos;
+	char * tmp = buf;
+
+	while (count-- > 0 && i < 65536) {
+		put_fs_byte(inb(i),tmp);
+		i++;
+		tmp++;
+	}
+	file->f_pos = i;
+	return tmp-buf;
+}
+
+static int write_port(struct inode * inode,struct file * file,char * buf, int count)
+{
+	unsigned int i = file->f_pos;
+	char * tmp = buf;
+
+	while (count-- > 0 && i < 65536) {
+		outb(get_fs_byte(tmp),i);
+		i++;
+		tmp++;
+	}
+	file->f_pos = i;
+	return tmp-buf;
+}
+
+static int read_null(struct inode * node,struct file * file,char * buf,int count)
+{
+	return 0;
+}
+
+static int write_null(struct inode * inode,struct file * file,char * buf, int count)
+{
+	return count;
+}
+
+static int read_zero(struct inode * node,struct file * file,char * buf,int count)
+{
+	int left;
+
+	for (left = count; left > 0; left--) {
+		put_fs_byte(0,buf);
+		buf++;
+	}
+	return count;
+}
+
+static int mmap_zero(struct inode * inode, struct file * file, struct vm_area_struct * vma)
+{
+	if (vma->vm_page_prot & PAGE_RW)
+		return -EINVAL;
+	if (zeromap_page_range(vma->vm_start, vma->vm_end - vma->vm_start, vma->vm_page_prot))
+		return -EAGAIN;
+	return 0;
+}
+
+static int read_full(struct inode * node,struct file * file,char * buf,int count)
+{
+	return count;
+}
+
+static int write_full(struct inode * inode,struct file * file,char * buf, int count)
+{
+	return -ENOSPC;
+}
+
+/*
+ * Special lseek() function for /dev/null and /dev/zero.  Most notably, you can fopen()
+ * both devices with "a" now.  This was previously impossible.  SRB.
+ */
+
+static int null_lseek(struct inode * inode, struct file * file, off_t offset, int orig)
+{
+	return file->f_pos=0;
+}
+/*
+ * The memory devices use the full 32 bits of the offset, and so we cannot
+ * check against negative addresses: they are ok. The return value is weird,
+ * though, in that case (0).
+ *
+ * also note that seeking relative to the "end of file" isn't supported:
+ * it has no meaning, so it returns -EINVAL.
+ */
+static int memory_lseek(struct inode * inode, struct file * file, off_t offset, int orig)
+{
+	switch (orig) {
+		case 0:
+			file->f_pos = offset;
+			return file->f_pos;
+		case 1:
+			file->f_pos += offset;
+			return file->f_pos;
+		default:
+			return -EINVAL;
+	}
+	if (file->f_pos < 0)
+		return 0;
+	return file->f_pos;
+}
+
+#define write_kmem	write_mem
+#define mmap_kmem	mmap_mem
+#define zero_lseek	null_lseek
+#define write_zero	write_null
+
+static struct file_operations ram_fops = {
+	memory_lseek,
+	read_ram,
+	write_ram,
+	NULL,		/* ram_readdir */
+	NULL,		/* ram_select */
+	NULL,		/* ram_ioctl */
+	NULL,		/* ram_mmap */
+	NULL,		/* no special open code */
+	NULL,		/* no special release code */
+	NULL		/* fsync */
+};
+
+static struct file_operations mem_fops = {
+	memory_lseek,
+	read_mem,
+	write_mem,
+	NULL,		/* mem_readdir */
+	NULL,		/* mem_select */
+	NULL,		/* mem_ioctl */
+	mmap_mem,
+	NULL,		/* no special open code */
+	NULL,		/* no special release code */
+	NULL		/* fsync */
+};
+
+static struct file_operations kmem_fops = {
+	memory_lseek,
+	read_kmem,
+	write_kmem,
+	NULL,		/* kmem_readdir */
+	NULL,		/* kmem_select */
+	NULL,		/* kmem_ioctl */
+	mmap_kmem,
+	NULL,		/* no special open code */
+	NULL,		/* no special release code */
+	NULL		/* fsync */
+};
+
+static struct file_operations null_fops = {
+	null_lseek,
+	read_null,
+	write_null,
+	NULL,		/* null_readdir */
+	NULL,		/* null_select */
+	NULL,		/* null_ioctl */
+	NULL,		/* null_mmap */
+	NULL,		/* no special open code */
+	NULL,		/* no special release code */
+	NULL		/* fsync */
+};
+
+static struct file_operations port_fops = {
+	memory_lseek,
+	read_port,
+	write_port,
+	NULL,		/* port_readdir */
+	NULL,		/* port_select */
+	NULL,		/* port_ioctl */
+	NULL,		/* port_mmap */
+	NULL,		/* no special open code */
+	NULL,		/* no special release code */
+	NULL		/* fsync */
+};
+
+static struct file_operations zero_fops = {
+	zero_lseek,
+	read_zero,
+	write_zero,
+	NULL,		/* zero_readdir */
+	NULL,		/* zero_select */
+	NULL,		/* zero_ioctl */
+	mmap_zero,
+	NULL,		/* no special open code */
+	NULL		/* no special release code */
+};
+
+static struct file_operations full_fops = {
+	memory_lseek,
+	read_full,
+	write_full,
+	NULL,		/* full_readdir */
+	NULL,		/* full_select */
+	NULL,		/* full_ioctl */	
+	NULL,		/* full_mmap */
+	NULL,		/* no special open code */
+	NULL		/* no special release code */
+};
+
+static int memory_open(struct inode * inode, struct file * filp)
+{
+	switch (MINOR(inode->i_rdev)) {
+		case 0:
+			filp->f_op = &ram_fops;
+			break;
+		case 1:
+			filp->f_op = &mem_fops;
+			break;
+		case 2:
+			filp->f_op = &kmem_fops;
+			break;
+		case 3:
+			filp->f_op = &null_fops;
+			break;
+		case 4:
+			filp->f_op = &port_fops;
+			break;
+		case 5:
+			filp->f_op = &zero_fops;
+			break;
+		case 7:
+			filp->f_op = &full_fops;
+			break;
+		default:
+			return -ENODEV;
+	}
+	if (filp->f_op && filp->f_op->open)
+		return filp->f_op->open(inode,filp);
+	return 0;
+}
+
+static struct file_operations memory_fops = {
+	NULL,		/* lseek */
+	NULL,		/* read */
+	NULL,		/* write */
+	NULL,		/* readdir */
+	NULL,		/* select */
+	NULL,		/* ioctl */
+	NULL,		/* mmap */
+	memory_open,	/* just a selector for the real open */
+	NULL,		/* release */
+	NULL		/* fsync */
+};
+
+#ifdef CONFIG_FTAPE
+char* ftape_big_buffer;
+#endif
+
+long chr_dev_init(long mem_start, long mem_end)
+{
+	if (register_chrdev(MEM_MAJOR,"mem",&memory_fops))
+		printk("unable to get major %d for memory devs\n", MEM_MAJOR);
+	mem_start = tty_init(mem_start);
+#ifdef CONFIG_PRINTER
+	mem_start = lp_init(mem_start);
+#endif
+#if defined (CONFIG_BUSMOUSE) || defined (CONFIG_82C710_MOUSE) || \
+    defined (CONFIG_PSMOUSE) || defined (CONFIG_MS_BUSMOUSE) || \
+    defined (CONFIG_ATIXL_BUSMOUSE)
+	mem_start = mouse_init(mem_start);
+#endif
+#ifdef CONFIG_SOUND
+	mem_start = soundcard_init(mem_start);
+#endif
+#if CONFIG_QIC02_TAPE
+	mem_start = qic02_tape_init(mem_start);
+#endif
+/*
+ *      Rude way to allocate kernel memory buffer for tape device
+ */
+#ifdef CONFIG_FTAPE
+        /* allocate NR_FTAPE_BUFFERS 32Kb buffers at aligned address */
+        ftape_big_buffer= (char*) ((mem_start + 0x7fff) & ~0x7fff);
+        printk( "ftape: allocated %d buffers aligned at: %p\n",
+               NR_FTAPE_BUFFERS, ftape_big_buffer);
+        mem_start = (long) ftape_big_buffer + NR_FTAPE_BUFFERS * 0x8000;
+#endif 
+	return mem_start;
+}