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Can someone help me replace "lock_kernel" with a block driver?

Thanks for watching this post. I am trying to fix a network block device driver. If you need to look at the sources, they are located at http://code.ximeta.com.

I noticed that lock_kernel () seems deprecated since Linux 2.6.37. I read the “New ioctl () Method” and found that device drivers should now perform a specific lock before starting work.

Therefore, I would like some advice to replace this, if possible.

I found two sections in the current code, which, it seems to me, is connected, in the block folder section.

Source 
      block->io.c
           ->ctrldev.c

I put excerpts from each for your consideration.

io.c contains one call to lock_kernel:

NDAS_SAL_API xbool     sal_file_get_size(sal_file file, xuint64* size)
{
    definitions and declarations etc..

lock_kernel();

#ifdef HAVE_UNLOCKED_IOCTL
    if (filp->f_op->unlocked_ioctl) {   
       some small statements

       error = filp->f_op->unlocked_ioctl(filp, BLKGETSIZE64, (unsigned long)size);

       actions if error or not etc.
   }
#endif

   unlock_kernel(); 
   return ret;
}

And ctrldev.c contains the main io function:

#include <linux/spinlock.h> // spinklock_t
#include <linux/semaphore.h> // struct semaphore
#include <asm/atomic.h> // atomic
#include <linux/interrupt.h>
#include <linux/fs.h>
#include <asm/uaccess.h>
#include <linux/ide.h>
#include <linux/smp_lock.h>
#include <linux/time.h>

......

int ndas_ctrldev_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg)
{
  lots of operations and functions. 

  return result;
}

ndas_ctrldev_ioctl .ioctl.

static struct file_operations ndasctrl_fops = {
    .write = ndas_ctrldev_write,
    .read = ndas_ctrldev_read,
    .open = ndas_ctrldev_open,
    .release = ndas_ctrldev_release,
    .ioctl = ndas_ctrldev_ioctl, 
};

, lock_kernel();

, , :

NDAS_SAL_API xbool     sal_file_get_size(sal_file file, xuint64* size)
{
    definitions and declarations etc..

#ifndef HAVE_UNLOCKED_IOCTL
    lock_kernel();
#endif

#ifdef HAVE_UNLOCKED_IOCTL
    if (filp->f_op->unlocked_ioctl) {   
       some small statements

       error = filp->f_op->unlocked_ioctl(filp, BLKGETSIZE64, (unsigned long)size);

       actions if error or not etc.
   }
#endif

#ifndef HAVE_UNLOCKED_IOCTL
   unlock_kernel(); 
#endif
   return ret;

}

#ifdef HAVE_UNLOCKED_IOCTL
long ndas_ctrldev_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
#else
int ndas_ctrldev_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg)
#endif
{

#ifdef HAVE_UNLOCKED_IOCTL
  ! add some sort of lock here !
#endif

  lots of operations and functions. 

#ifdef HAVE_UNLOCKED_IOCTL
  ! add unlock statement here  !
#endif
  return result;
}

static struct file_operations ndasctrl_fops = {
    .write = ndas_ctrldev_write,
    .read = ndas_ctrldev_read,
    .open = ndas_ctrldev_open,
    .release = ndas_ctrldev_release,
#ifdef HAVE_UNLOCKED_IOCTL
    .unlocked_ioctl = ndas_ctrldev_ioctl, 
#else
    .ioctl = ndas_ctrldev_ioctl, 
#endif
};

, .

  • proceedure?

  • , io-?

  • crtrldev.c, ? ( , lock_kernel, noob, .)

+5
2

(BKL) - 2.6.39 .

lock_kernel() , . , lock_kernel() unlock_kernel() / . , , , BKL ( lock_kernel(), ), ; / .

, BKL ; , , ( reiserfs, BKL, , ).

, .

+5

.

#if HAVE_UNLOCKED_IOCTL
    #include <linux/mutex.h>
#else
    #include <linux/smp_lock.h>
#endif

.
. 
. 

#if HAVE_UNLOCKED_IOCTL
   mutex_lock(&fs_mutex);
#else
   lock_kernel();
#endif

. , , unlocked_ioctl. .

+5

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