[PATCH v2 0/5] nbd: fixes for nbd

[Pranay Kr. Srivastava]

This patch series fixes the following

1) fix might_sleep warning on socket shutdown:
   Fix sock_shutdown to avoid calling kernel_sock_shutdown
   while holding spin_lock.

2) cleanup nbd_set_socket
   Cleanup nbd_set_socket to use spin_lock instead of
   irq version and remove the goto statement in favour
   of a simple if-else statement.

3) fix various coding standard warnings
   Make shutdown get called in a process context instead, using
   system_wq.

4) make nbd device wait for its users.
   When a timeout or error occurs then nbd driver simply kills
   the block device. Many filesystem(s) example ext2/ext3 don't
   expect their buffer heads to disappear like that. Fix this
   by making nbd device wait for its users.

   Introduced a new field to check if the device is currently
   in use or not. This helps to check if the kref_put should
   be done on device release or not.
   
   This field needs to be atomic as the release function may
   be called from NBD_DO_IT as well as from device's release
   function.

5) use device_attr macros for sysfs attribute
   use DEVICE_ATTR_RO for sysfs pid attribute.

Changelog for v2:
1) fix might_sleep warning on socket shutdown
   use bool timedout instead of atomic

2) cleanup nbd_set_socket
   Added this new patch to this series.

3) fix various coding standard warnings
   No Change.

4) make nbd device wait for its users
   Earlier version used to do a final kref put when
   the kref->counter == 2. This required a check of
   the internal atomic counter of kref which was ugly.

   v2 of this patch make this more readable and doesn't
   do manual check of the internal counter used by kref.

5) use device_attr macros for sysfs attribute
   No Change.

Pranay Kr. Srivastava (5):
  fix might_sleep warning on socket shutdown.
  cleanup nbd_set_socket
  fix various coding standard warnings
  make nbd device wait for its users.
  use device_attr macros for sysfs attribute

 drivers/block/nbd.c | 173 +++++++++++++++++++++++++++++++++++++---------------
 1 file changed, 124 insertions(+), 49 deletions(-)

-- 
2.6.2