Import of Linux/MIPS 2.1.36

1 files changed, 289 insertions, 0 deletions

diff --git a/fs/proc/generic.c b/fs/proc/generic.c
new file mode 100644
index 000000000..6e80e8298
--- /dev/null
+++ b/fs/proc/generic.c
@@ -0,0 +1,289 @@
+/*
+ * proc/fs/generic.c --- generic routines for the proc-fs
+ *
+ * This file contains generic proc-fs routines for handling
+ * directories and files.
+ * 
+ * Copyright (C) 1991, 1992 Linus Torvalds.
+ * Copyright (C) 1997 Theodore Ts'o
+ */
+
+#include <asm/uaccess.h>
+
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/proc_fs.h>
+#include <linux/stat.h>
+#include <asm/bitops.h>
+
+static long proc_file_read(struct inode * inode, struct file * file,
+			   char * buf, unsigned long nbytes);
+static long proc_file_write(struct inode * inode, struct file * file,
+			    const char * buffer, unsigned long count);
+static long long proc_file_lseek(struct inode * inode, struct file * file, 
+				 long long offset, int orig);
+
+static struct file_operations proc_file_operations = {
+    proc_file_lseek,	/* lseek   */
+    proc_file_read,	/* read	   */
+    proc_file_write,	/* write   */
+    NULL,		/* readdir */
+    NULL,		/* poll    */
+    NULL,		/* ioctl   */
+    NULL,		/* mmap	   */
+    NULL,		/* no special open code	   */
+    NULL,		/* no special release code */
+    NULL		/* can't fsync */
+};
+
+/*
+ * proc files can do almost nothing..
+ */
+struct inode_operations proc_file_inode_operations = {
+    &proc_file_operations,  /* default proc file-ops */
+    NULL,	    /* create	   */
+    NULL,	    /* lookup	   */
+    NULL,	    /* link	   */
+    NULL,	    /* unlink	   */
+    NULL,	    /* symlink	   */
+    NULL,	    /* mkdir	   */
+    NULL,	    /* rmdir	   */
+    NULL,	    /* mknod	   */
+    NULL,	    /* rename	   */
+    NULL,	    /* readlink	   */
+    NULL,	    /* follow_link */
+    NULL,	    /* readpage	   */
+    NULL,	    /* writepage   */
+    NULL,	    /* bmap	   */
+    NULL,	    /* truncate	   */
+    NULL	    /* permission  */
+};
+
+/*
+ * compatibility to replace fs/proc/net.c
+ */
+struct inode_operations proc_net_inode_operations = {
+	&proc_file_operations,	/* default net file-ops */
+	NULL,			/* create */
+	NULL,			/* lookup */
+	NULL,			/* link */
+	NULL,			/* unlink */
+	NULL,			/* symlink */
+	NULL,			/* mkdir */
+	NULL,			/* rmdir */
+	NULL,			/* mknod */
+	NULL,			/* rename */
+	NULL,			/* readlink */
+	NULL,			/* follow_link */
+	NULL,			/* readpage */
+	NULL,			/* writepage */
+	NULL,			/* bmap */
+	NULL,			/* truncate */
+	NULL			/* permission */
+};
+
+
+#ifndef MIN
+#define MIN(a,b) (((a) < (b)) ? (a) : (b))
+#endif
+
+/* 4K page size but our output routines use some slack for overruns */
+#define PROC_BLOCK_SIZE	(3*1024)
+
+static long proc_file_read(struct inode * inode, struct file * file,
+			   char * buf, unsigned long nbytes)
+{
+	char 	*page;
+	int	retval=0;
+	int	eof=0;
+	int	n, count;
+	char	*start;
+	struct proc_dir_entry * dp;
+
+	if (nbytes < 0)
+		return -EINVAL;
+	dp = (struct proc_dir_entry *) inode->u.generic_ip;
+	if (!(page = (char*) __get_free_page(GFP_KERNEL)))
+		return -ENOMEM;
+
+	while ((nbytes > 0) && !eof)
+	{
+		count = MIN(PROC_BLOCK_SIZE, nbytes);
+
+		start = NULL;
+		if (dp->get_info) {
+			/*
+			 * Handle backwards compatibility with the old net
+			 * routines.
+			 * 
+			 * XXX What gives with the file->f_flags & O_ACCMODE
+			 * test?  Seems stupid to me....
+			 */
+			n = dp->get_info(page, &start, file->f_pos, count,
+				 (file->f_flags & O_ACCMODE) == O_RDWR);
+			if (n < count)
+				eof = 1;
+		} else if (dp->read_proc) {
+			n = dp->read_proc(page, &start, file->f_pos,
+					  count, &eof, dp->data);
+		} else
+			break;
+			
+		if (!start) {
+			/*
+			 * For proc files that are less than 4k
+			 */
+			start = page + file->f_pos;
+			n -= file->f_pos;
+			if (n <= 0)
+				break;
+			if (n > count)
+				n = count;
+		}
+		if (n == 0)
+			break;	/* End of file */
+		if (n < 0) {
+			if (retval == 0)
+				retval = n;
+			break;
+		}
+		
+		n -= copy_to_user(buf, start, n);
+		if (n == 0) {
+			if (retval == 0)
+				retval = -EFAULT;
+			break;
+		}
+		
+		file->f_pos += n;	/* Move down the file */
+		nbytes -= n;
+		buf += n;
+		retval += n;
+	}
+	free_page((unsigned long) page);
+	return retval;
+}
+
+static long
+proc_file_write(struct inode * inode, struct file * file,
+		const char * buffer, unsigned long count)
+{
+	struct proc_dir_entry * dp;
+	
+	if (count < 0)
+		return -EINVAL;
+	dp = (struct proc_dir_entry *) inode->u.generic_ip;
+
+	if (!dp->write_proc)
+		return -EIO;
+
+	return dp->write_proc(file, buffer, count, dp->data);
+}
+
+
+static long long proc_file_lseek(struct inode * inode, struct file * file, 
+				 long long 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);
+    case 2:
+	return(-EINVAL);
+    default:
+	return(-EINVAL);
+    }
+}
+
+/*
+ * This function parses a name such as "tty/driver/serial", and
+ * returns the struct proc_dir_entry for "/proc/tty/driver", and
+ * returns "serial" in residual.
+ */
+static int xlate_proc_name(const char *name,
+			   struct proc_dir_entry **ret, const char **residual)
+{
+	const char     		*cp = name, *next;
+	struct proc_dir_entry	*de;
+	int			len;
+
+	de = &proc_root;
+	while (1) {
+		next = strchr(cp, '/');
+		if (!next)
+			break;
+
+		len = next - cp;
+		for (de = de->subdir; de ; de = de->next) {
+			if (proc_match(len, cp, de))
+				break;
+		}
+		if (!de)
+			return -ENOENT;
+		cp += len + 1;
+	}
+	*residual = cp;
+	*ret = de;
+	return 0;
+}
+
+struct proc_dir_entry *create_proc_entry(const char *name, mode_t mode,
+					 struct proc_dir_entry *parent)
+{
+	struct proc_dir_entry *ent;
+	const char *fn;
+
+	if (parent)
+		fn = name;
+	else {
+		if (xlate_proc_name(name, &parent, &fn))
+			return NULL;
+	}
+
+	ent = kmalloc(sizeof(struct proc_dir_entry), GFP_KERNEL);
+	if (!ent)
+		return NULL;
+	memset(ent, 0, sizeof(struct proc_dir_entry));
+
+	if (mode == S_IFDIR)
+		mode |= S_IRUGO | S_IXUGO;
+	else if (mode == 0)
+		mode = S_IFREG | S_IRUGO;
+	
+	ent->name = fn;
+	ent->namelen = strlen(fn);
+	ent->mode = mode;
+	if (S_ISDIR(mode)) 
+		ent->nlink = 2;
+	else
+		ent->nlink = 1;
+
+	proc_register(parent, ent);
+	
+	return ent;
+}
+
+void remove_proc_entry(const char *name, struct proc_dir_entry *parent)
+{
+	struct proc_dir_entry *de;
+	const char *fn;
+	int len;
+
+	if (parent)
+		fn = name;
+	else 
+		if (xlate_proc_name(name, &parent, &fn))
+			return;
+	len = strlen(fn);
+
+	for (de = parent->subdir; de ; de = de->next) {
+		if (proc_match(len, fn, de))
+			break;
+	}
+	if (de)
+		proc_unregister(parent, de->low_ino);
+	kfree(de);
+}