Commit d7b92e1d authored by Andrew Morton's avatar Andrew Morton Committed by Linus Torvalds

[PATCH] nbd: cleanup PARANOIA usage & code

From: Lou Langholtz <ldl@aros.net>

This fifth patch cleans up usage of the PARANOIA sanity checking macro and
code.  This patch modifies both drivers/block/nbd.c and
include/linux/nbd.h.  It's intended to be applied incrementally on top of
my fourth patch (4.1 really if you count the memset addition as .1's worth)
that simply removed unneeded blksize_bits field.  Again, I wanted to get
this smaller change out of the way before my next patch will is much more
major.
parent 4f9420c6
......@@ -35,13 +35,13 @@
* 03-06-23 Enhance diagnostics support. <ldl@aros.net>
* 03-06-24 Remove unneeded blksize_bits field from nbd_device struct.
* <ldl@aros.net>
* 03-06-24 Cleanup PARANOIA usage & code. <ldl@aros.net>
*
* possible FIXME: make set_sock / set_blksize / set_size / do_it one syscall
* why not: would need verify_area and friends, would share yet another
* structure with userland
*/
#define PARANOIA
#include <linux/major.h>
#include <linux/blk.h>
......@@ -64,9 +64,12 @@
#include <asm/uaccess.h>
#include <asm/types.h>
/* Define PARANOIA in linux/nbd.h to turn on extra sanity checking */
#include <linux/nbd.h>
#ifdef PARANOIA
#define LO_MAGIC 0x68797548
#endif
#ifdef NDEBUG
#define dprintk(flags, fmt...)
......@@ -99,8 +102,10 @@ static struct nbd_device nbd_dev[MAX_NBD];
*/
static spinlock_t nbd_lock = SPIN_LOCK_UNLOCKED;
#ifdef PARANOIA
static int requests_in;
static int requests_out;
#endif
#ifndef NDEBUG
static const char *ioctl_cmd_to_ascii(int cmd)
......@@ -397,7 +402,9 @@ void nbd_do_it(struct nbd_device *lo)
{
struct request *req;
#ifdef PARANOIA
BUG_ON(lo->magic != LO_MAGIC);
#endif
while ((req = nbd_read_stat(lo)) != NULL)
nbd_end_request(req);
printk(KERN_NOTICE "%s: req should never be null\n",
......@@ -409,7 +416,9 @@ void nbd_clear_que(struct nbd_device *lo)
{
struct request *req;
#ifdef PARANOIA
BUG_ON(lo->magic != LO_MAGIC);
#endif
do {
req = NULL;
......@@ -448,7 +457,9 @@ static void do_nbd_request(request_queue_t * q)
goto error_out;
lo = req->rq_disk->private_data;
#ifdef PARANOIA
BUG_ON(lo->magic != LO_MAGIC);
#endif
if (!lo->file) {
printk(KERN_ERR "%s: Request when not-ready\n",
lo->disk->disk_name);
......@@ -463,7 +474,9 @@ static void do_nbd_request(request_queue_t * q)
goto error_out;
}
}
#ifdef PARANOIA
requests_in++;
#endif
req->errors = 0;
spin_unlock_irq(q->queue_lock);
......@@ -522,11 +535,13 @@ static int nbd_release(struct inode *inode, struct file *file)
{
struct nbd_device *lo = inode->i_bdev->bd_disk->private_data;
#ifdef PARANOIA
if (lo->refcnt <= 0) {
printk(KERN_ALERT "%s: nbd_release: refcount(%d) <= 0\n",
lo->disk->disk_name, lo->refcnt);
BUG();
}
#endif
lo->refcnt--;
dprintk(DBG_RELEASE, "%s: nbd_release: refcnt=%d\n",
lo->disk->disk_name, lo->refcnt);
......@@ -540,6 +555,9 @@ static int nbd_ioctl(struct inode *inode, struct file *file,
int error;
struct request sreq ;
#ifdef PARANOIA
BUG_ON(lo->magic != LO_MAGIC);
#endif
/* Anyone capable of this syscall can do *real bad* things */
dprintk(DBG_IOCTL, "%s: nbd_ioctl cmd=%s(0x%x) arg=%lu\n",
lo->disk->disk_name, ioctl_cmd_to_ascii(cmd), cmd, arg);
......@@ -642,13 +660,17 @@ static int nbd_ioctl(struct inode *inode, struct file *file,
case NBD_CLEAR_QUE:
nbd_clear_que(lo);
return 0;
#ifdef PARANOIA
case NBD_PRINT_DEBUG:
#ifdef PARANOIA
printk(KERN_INFO "%s: next = %p, prev = %p. Global: in %d, out %d\n",
inode->i_bdev->bd_disk->disk_name, lo->queue_head.next,
lo->queue_head.prev, requests_in, requests_out);
return 0;
#else
printk(KERN_INFO "%s: next = %p, prev = %p\n",
inode->i_bdev->bd_disk->disk_name,
lo->queue_head.next, lo->queue_head.prev);
#endif
return 0;
}
return -EINVAL;
}
......@@ -671,10 +693,12 @@ static int __init nbd_init(void)
int err = -ENOMEM;
int i;
#ifdef PARANOIA
if (sizeof(struct nbd_request) != 28) {
printk(KERN_CRIT "nbd: Sizeof nbd_request needs to be 28 in order to work!\n" );
return -EIO;
}
#endif
for (i = 0; i < MAX_NBD; i++) {
struct gendisk *disk = alloc_disk(1);
......@@ -708,7 +732,9 @@ static int __init nbd_init(void)
struct gendisk *disk = nbd_dev[i].disk;
nbd_dev[i].refcnt = 0;
nbd_dev[i].file = NULL;
#ifdef PARANOIA
nbd_dev[i].magic = LO_MAGIC;
#endif
nbd_dev[i].flags = 0;
spin_lock_init(&nbd_dev[i].queue_lock);
INIT_LIST_HEAD(&nbd_dev[i].queue_head);
......
......@@ -7,6 +7,7 @@
* layer code.
* 2003/06/24 Louis D. Langholtz <ldl@aros.net>
* Removed unneeded blksize_bits field from nbd_device struct.
* Cleanup PARANOIA usage & code.
*/
#ifndef LINUX_NBD_H
......@@ -28,16 +29,12 @@ enum {
NBD_CMD_DISC = 2
};
#ifdef PARANOIA
extern int requests_in;
extern int requests_out;
#endif
#define nbd_cmd(req) ((req)->cmd[0])
#define MAX_NBD 128
/* Define PARANOIA to include extra sanity checking code in here & driver */
#define PARANOIA
struct nbd_device {
int refcnt;
int flags;
......@@ -46,7 +43,9 @@ struct nbd_device {
#define NBD_WRITE_NOCHK 0x0002
struct socket * sock;
struct file * file; /* If == NULL, device is not ready, yet */
#ifdef PARANOIA
int magic; /* FIXME: not if debugging is off */
#endif
spinlock_t queue_lock;
struct list_head queue_head;/* Requests are added here... */
struct semaphore tx_lock;
......
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