On Thu, Apr 30, 2009 at 01:30:07PM +0300, Boaz Harrosh wrote:
> > Incidentally, what the hell is going with ->i_cdev in there? Boaz?
>
> Thanks for asking. The thing is that this function is called from within
> the kernel by exofs. Now I have found that if user-mode as never opened
> an handle on my char-device, then inode->i_cdev is NULL even though it is
> registered and found. My mount utility for exofs does an open/close on the
> char-device before calling the Kernel mounter, but this is just a script
> and can be missed by users. (I guess I need to submit an mount.exofs. where
> should it be submitted?)
>
> Alternatively we perhaps need a udev rule that, one - loads osd.ko when
> OSD_TYPE devices are discovered by scsi (like sd), and two - do the above
> open/close. I was meaning to ask someone about these things.
IDGI. Why not simply do filp_open() and keep struct file * until the
end to pin the thing down? And turn your function into
check that file->f_op is &osd_fops, if it isn't - ERR_PTR(-EINVAL),
if it is - &((...)file->private_data)->od
IOW, how about something like this (on top of previous patches)?
diff --git a/drivers/scsi/osd/osd_uld.c b/drivers/scsi/osd/osd_uld.c
index 22b59e1..38b4a26 100644
--- a/drivers/scsi/osd/osd_uld.c
+++ b/drivers/scsi/osd/osd_uld.c
@@ -173,68 +173,21 @@ static const struct file_operations osd_fops = {
.unlocked_ioctl = osd_uld_ioctl,
};
-struct osd_dev *osduld_path_lookup(const char *name)
+struct osd_dev *osduld_device(struct file *file)
{
- struct path path;
- struct inode *inode;
- struct cdev *cdev;
- struct osd_uld_device *uninitialized_var(oud);
- int error;
-
- if (!name || !*name) {
- OSD_ERR("Mount with !path || !*path\n");
- return ERR_PTR(-EINVAL);
- }
-
- error = kern_path(name, LOOKUP_FOLLOW, &path);
- if (error) {
- OSD_ERR("path_lookup of %s failed=>%d\n", name, error);
- return ERR_PTR(error);
- }
-
- inode = path.dentry->d_inode;
- error = -EINVAL; /* Not the right device e.g osd_uld_device */
- if (!S_ISCHR(inode->i_mode)) {
- OSD_DEBUG("!S_ISCHR()\n");
- goto out;
- }
-
- cdev = inode->i_cdev;
- if (!cdev) {
- OSD_ERR("Before mounting an OSD Based filesystem\n");
- OSD_ERR(" user-mode must open+close the %s device\n", name);
- OSD_ERR(" Example: bash: echo < %s\n", name);
- goto out;
- }
+ struct osd_uld_device *oud;
/* The Magic wand. Is it our char-dev */
/* TODO: Support sg devices */
- if (cdev->owner != THIS_MODULE) {
+ if (file->f_op != &osd_fops) {
OSD_ERR("Error mounting %s - is not an OSD device\n", name);
- goto out;
+ return ERR_PTR(-EINVAL);
}
- oud = container_of(cdev, struct osd_uld_device, cdev);
-
- __uld_get(oud);
- error = 0;
-
-out:
- path_put(&path);
- return error ? ERR_PTR(error) : &oud->od;
-}
-EXPORT_SYMBOL(osduld_path_lookup);
-
-void osduld_put_device(struct osd_dev *od)
-{
- if (od) {
- struct osd_uld_device *oud = container_of(od,
- struct osd_uld_device, od);
-
- __uld_put(oud);
- }
+ oud = file->private_data;
+ return &oud->od;
}
-EXPORT_SYMBOL(osduld_put_device);
+EXPORT_SYMBOL(osduld_device);
/*
* Scsi Device operations
diff --git a/fs/exofs/exofs.h b/fs/exofs/exofs.h
index 0fd4c78..45e41f2 100644
--- a/fs/exofs/exofs.h
+++ b/fs/exofs/exofs.h
@@ -57,6 +57,7 @@
* our extension to the in-memory superblock
*/
struct exofs_sb_info {
+ struct file *s_file; /* underlying file */
struct osd_dev *s_dev; /* returned by get_osd_dev */
osd_id s_pid; /* partition ID of file system*/
int s_timeout; /* timeout for OSD operations */
diff --git a/fs/exofs/super.c b/fs/exofs/super.c
index 3cdb761..c3fcb6d 100644
--- a/fs/exofs/super.c
+++ b/fs/exofs/super.c
@@ -35,9 +35,10 @@
#include <linux/string.h>
#include <linux/parser.h>
-#include <linux/vfs.h>
+#include <linux/statfs.h>
#include <linux/random.h>
#include <linux/exportfs.h>
+#include <linux/file.h>
#include "exofs.h"
@@ -271,7 +272,7 @@ static void exofs_put_super(struct super_block *sb)
msecs_to_jiffies(100));
}
- osduld_put_device(sbi->s_dev);
+ fput(sbi->s_file);
kfree(sb->s_fs_info);
sb->s_fs_info = NULL;
}
@@ -295,13 +296,15 @@ static int exofs_fill_super(struct super_block *sb, void *data, int silent)
sb->s_fs_info = sbi;
/* use mount options to fill superblock */
- sbi->s_dev = osduld_path_lookup(opts->dev_name);
- if (IS_ERR(sbi->s_dev)) {
- ret = PTR_ERR(sbi->s_dev);
- sbi->s_dev = NULL;
+ sbi->s_file = filp_open(opts->dev_name, O_RDWR, 0);
+ ret = PTR_ERR(sbi->s_file);
+ if (IS_ERR(sbi->s_file))
goto free_sbi;
- }
+ sbi->s_dev = osduld_device(sbi->s_file);
+ ret = PTR_ERR(sbi->s_dev);
+ if (IS_ERR(sbi->s_dev))
+ goto close_sbi;
sbi->s_pid = opts->pid;
sbi->s_timeout = opts->timeout;
@@ -326,7 +329,7 @@ static int exofs_fill_super(struct super_block *sb, void *data, int silent)
EXOFS_ERR(
"exofs_fill_super: osd_start_request failed.\n");
ret = -ENOMEM;
- goto free_sbi;
+ goto close_sbi;
}
ret = osd_req_read_kern(or, &obj, 0, &fscb, sizeof(fscb));
if (unlikely(ret)) {
@@ -334,7 +337,7 @@ static int exofs_fill_super(struct super_block *sb, void *data, int silent)
EXOFS_ERR(
"exofs_fill_super: osd_req_read_kern failed.\n");
ret = -ENOMEM;
- goto free_sbi;
+ goto close_sbi;
}
ret = exofs_sync_op(or, sbi->s_timeout, sbi->s_cred);
@@ -342,7 +345,7 @@ static int exofs_fill_super(struct super_block *sb, void *data, int silent)
if (!silent)
EXOFS_ERR("exofs_fill_super: exofs_sync_op failed.\n");
ret = -EIO;
- goto free_sbi;
+ goto close_sbi;
}
sb->s_magic = le16_to_cpu(fscb.s_magic);
@@ -354,7 +357,7 @@ static int exofs_fill_super(struct super_block *sb, void *data, int silent)
if (!silent)
EXOFS_ERR("ERROR: Bad magic value\n");
ret = -EINVAL;
- goto free_sbi;
+ goto close_sbi;
}
/* start generation numbers from a random point */
@@ -368,14 +371,14 @@ static int exofs_fill_super(struct super_block *sb, void *data, int silent)
if (IS_ERR(root)) {
EXOFS_ERR("ERROR: exofs_iget failed\n");
ret = PTR_ERR(root);
- goto free_sbi;
+ goto close_sbi;
}
sb->s_root = d_alloc_root(root);
if (!sb->s_root) {
iput(root);
EXOFS_ERR("ERROR: get root inode failed\n");
ret = -ENOMEM;
- goto free_sbi;
+ goto close_sbi;
}
if (!S_ISDIR(root->i_mode)) {
@@ -384,7 +387,7 @@ static int exofs_fill_super(struct super_block *sb, void *data, int silent)
EXOFS_ERR("ERROR: corrupt root inode (mode = %hd)\n",
root->i_mode);
ret = -EINVAL;
- goto free_sbi;
+ goto close_sbi;
}
ret = 0;
@@ -393,8 +396,9 @@ out:
osd_end_request(or);
return ret;
+close_sbi:
+ fput(sbi->s_file);
free_sbi:
- osduld_put_device(sbi->s_dev); /* NULL safe */
kfree(sbi);
goto out;
}
diff --git a/include/scsi/osd_initiator.h b/include/scsi/osd_initiator.h
index b24d961..f9b6847 100644
--- a/include/scsi/osd_initiator.h
+++ b/include/scsi/osd_initiator.h
@@ -55,8 +55,8 @@ struct osd_dev {
};
/* Retrieve/return osd_dev(s) for use by Kernel clients */
-struct osd_dev *osduld_path_lookup(const char *dev_name); /*Use IS_ERR/ERR_PTR*/
-void osduld_put_device(struct osd_dev *od);
+struct file;
+struct osd_dev *osduld_device(struct file *); /*Use IS_ERR/ERR_PTR*/
/* Add/remove test ioctls from external modules */
typedef int (do_test_fn)(struct osd_dev *od, unsigned cmd, unsigned long arg);
--
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
