From b5db8fc05a77ad3c47ceed4f9afbb67507f2a298 Mon Sep 17 00:00:00 2001
From: wangdi <wangdi>
Date: Tue, 3 Feb 2004 16:39:38 +0000
Subject: [PATCH] update smfs. 1)fix bugs in sm_read_super 2) add some methods
in symlink ops
---
lustre/smfs/super.c | 183 +++++++++++++++++++++++++++---------------
lustre/smfs/symlink.c | 27 ++++++-
2 files changed, 145 insertions(+), 65 deletions(-)
diff --git a/lustre/smfs/super.c b/lustre/smfs/super.c
index 2cb0346758..8e8cdd95ac 100644
--- a/lustre/smfs/super.c
+++ b/lustre/smfs/super.c
@@ -45,21 +45,6 @@ static char *smfs_options(char *options, char **devstr, char **namestr)
}
return pos;
}
-static int get_fd(struct file *filp)
-{
- struct files_struct *files = current->files;
- int fd = 0;
-
- write_lock(&files->file_lock);
- for (fd = 0; fd < files->max_fds; fd++) {
- if(files->fd[fd] == filp) {
- write_unlock(&files->file_lock);
- return fd;
- }
- }
- write_unlock(&files->file_lock);
- RETURN(-1);
-}
static int close_fd(int fd)
{
struct files_struct *files = current->files;
@@ -72,65 +57,137 @@ static int close_fd(int fd)
write_unlock(&files->file_lock);
return 0;
}
-
-#define MAX_LOOP_DEVICES 256
-static char *parse_path2dev(struct super_block *sb, char *dev_path)
+static int set_loop_fd(char *dev_path, char *loop_dev)
{
+ struct loop_info loopinfo;
+ struct nameidata nd;
+ struct dentry *dentry;
+ struct block_device_operations *bd_ops;
struct file *filp;
- int i = 0, fd = 0, error = 0;
- char *name = NULL;
-
+ int fd = 0, error = 0;
+
+ fd = get_unused_fd();
+
+ if (!fd) RETURN(-EINVAL);
+
filp = filp_open(dev_path, 0, 0);
- if (!filp)
- RETURN(NULL);
- if (S_ISREG(filp->f_dentry->d_inode->i_mode)) {
- /*here we must walk through all the snap cache to
- *find the loop device */
-
- fd = get_unused_fd();
- if (!fd) RETURN(NULL);
+ if (!filp || !S_ISREG(filp->f_dentry->d_inode->i_mode))
+ RETURN(-EINVAL);
+
+ fd_install(fd, filp);
- fd_install(fd, filp);
- SM_ALLOC(name, strlen("/dev/loop/") + 2);
+ if (path_init(loop_dev, LOOKUP_FOLLOW, &nd)) {
+ error = path_walk(loop_dev, &nd);
+ if (error) {
+ path_release(&nd);
+ filp_close(filp, current->files);
+ RETURN(-EINVAL);
+ }
+ } else {
+ path_release(&nd);
+ filp_close(filp, current->files);
+ RETURN(-EINVAL);
+ }
+ dentry = nd.dentry;
+ bd_ops = get_blkfops(LOOP_MAJOR);
- for (i = 0; i < MAX_LOOP_DEVICES; i++) {
- fd = get_fd(filp);
- if (fd > 0) {
- struct block_device_operations *bd_ops;
- struct dentry *dentry;
- struct nameidata nd;
- /*FIXME later, the loop file should
- *be different for different system*/
-
- sprintf(name, "/dev/loop/%d", i);
-
- if (path_init(name, LOOKUP_FOLLOW, &nd)) {
- error = path_walk(name, &nd);
- if (error) {
- path_release(&nd);
- SM_FREE(name, sizeof(name) + 1);
- RETURN(NULL);
- }
- } else {
- SM_FREE(name, sizeof(name) + 1);
- RETURN(NULL);
- }
- dentry = nd.dentry;
- bd_ops = get_blkfops(LOOP_MAJOR);
- error = bd_ops->ioctl(dentry->d_inode,
- filp, LOOP_SET_FD,
- (unsigned long)fd);
- path_release(&nd);
- if (!error) {
- filp_close(filp, current->files);
- RETURN(name);
+ error = bd_ops->ioctl(dentry->d_inode, filp, LOOP_SET_FD,
+ (unsigned long)fd);
+ if (error) {
+ path_release(&nd);
+ filp_close(filp, current->files);
+ RETURN(-EINVAL);
+ }
+ memset(&loopinfo, 0, sizeof(struct loop_info));
+
+ error = bd_ops->ioctl(dentry->d_inode, filp, LOOP_SET_STATUS,
+ (unsigned long)(&loopinfo));
+ path_release(&nd);
+ RETURN(error);
+}
+
+#define SIZE(a) (sizeof(a)/sizeof(a[0]))
+static char *find_unused_and_set_loop_device(char *dev_path)
+{
+ char *loop_formats[] = { "/dev/loop%d", "/dev/loop/%d" };
+ struct loop_info loopinfo;
+ struct nameidata nd;
+ struct dentry *dentry;
+ char *dev = NULL;
+ int i, j, error;
+
+ for (j = 0; j < SIZE(loop_formats); j++) {
+ SM_ALLOC(dev, strlen(loop_formats[i]) + 1);
+ for(i = 0; i < 256; i++) {
+ struct block_device_operations *bd_ops;
+
+ sprintf(dev, loop_formats[j], i);
+
+ if (path_init(dev, LOOKUP_FOLLOW, &nd)) {
+ error = path_walk(dev, &nd);
+ if (error) {
+ path_release(&nd);
+ SM_FREE(dev, strlen(loop_formats[i]) + 1);
+ RETURN(NULL);
+ }
+ } else {
+ SM_FREE(dev, strlen(loop_formats[i]) + 1);
+ RETURN(NULL);
+ }
+ dentry = nd.dentry;
+ bd_ops = get_blkfops(LOOP_MAJOR);
+ error = bd_ops->ioctl(dentry->d_inode, NULL, LOOP_GET_STATUS,
+ (unsigned long)&loopinfo);
+ path_release(&nd);
+
+ if (error == ENXIO) {
+ /*find unused loop and set dev_path to loopdev*/
+ error = set_loop_fd(dev_path, dev);
+ if (error) {
+ SM_FREE(dev, strlen(loop_formats[i]) + 1);
+ dev = NULL;
}
+ return dev;/* probably free */
}
+ }
+ SM_FREE(dev, strlen(loop_formats[i]) + 1);
+ }
+ RETURN(NULL);
+}
+
+#define MAX_LOOP_DEVICES 256
+static char *parse_path2dev(struct super_block *sb, char *dev_path)
+{
+ struct dentry *dentry;
+ struct nameidata nd;
+ char *name = NULL;
+ int error = 0;
+
+ if (path_init(name, LOOKUP_FOLLOW, &nd)) {
+ error = path_walk(name, &nd);
+ if (error) {
+ path_release(&nd);
+ RETURN(NULL);
}
+ } else {
+ RETURN(NULL);
+ }
+ dentry = nd.dentry;
+
+ if (!dentry->d_inode || is_bad_inode(dentry->d_inode) ||
+ (!S_ISBLK(dentry->d_inode->i_mode) &&
+ !S_ISREG(dentry->d_inode->i_mode))){
+ path_release(&nd);
+ RETURN(NULL);
+ }
+
+ if (S_ISREG(dentry->d_inode->i_mode)) {
+ name = find_unused_and_set_loop_device(dev_path);
+ path_release(&nd);
+ RETURN(name);
}
SM_ALLOC(name, strlen(dev_path) + 1);
memcpy(name, dev_path, strlen(dev_path) + 1);
- filp_close(filp, current->files);
RETURN(name);
}
extern struct super_operations smfs_super_ops;
diff --git a/lustre/smfs/symlink.c b/lustre/smfs/symlink.c
index 4174846185..72c68f4a68 100644
--- a/lustre/smfs/symlink.c
+++ b/lustre/smfs/symlink.c
@@ -1,7 +1,6 @@
/*
- * fs/snap/snap.c
+ * smfs/symlink.c
*
- * A snap shot file system.
*
*/
#define DEBUG_SUBSYSTEM S_SNAP
@@ -14,7 +13,31 @@
#include "smfs_internal.h"
+static int smfs_readlink(struct dentry * dentry, char * buffer, int buflen)
+{
+ struct inode *cache_inode = I2CI(dentry->d_inode);
+ int rc = 0;
+
+ if (cache_inode->i_op && cache_inode->i_op->readlink)
+ rc = cache_inode->i_op->readlink(dentry, buffer, buflen);
+
+ return rc;
+}
+
+static int smfs_follow_link(struct dentry *dentry, struct nameidata *nd)
+{
+ struct inode *cache_inode = I2CI(dentry->d_inode);
+ int rc = 0;
+
+ if (cache_inode->i_op && cache_inode->i_op->follow_link)
+ rc = cache_inode->i_op->follow_link(dentry, nd);
+
+ return rc;
+
+}
struct inode_operations smfs_sym_iops = {
+ readlink: smfs_readlink,
+ follow_link: smfs_follow_link,
};
struct file_operations smfs_sym_fops = {
--
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