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-rw-r--r--fs/proc/generic.c289
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);
+}
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