Skip to content

R
raspberrypi-kernel

openeuler / raspberrypi-kernel

通知 13
Star 1
Fork 0
R
raspberrypi-kernel
切换分支/标签
  1. 24 3月, 2011 1 次提交
  3. 21 3月, 2011 5 次提交
    • S
      introduce sys_syncfs to sync a single file system · b7ed78f5
      由 Sage Weil 提交于 
      It is frequently useful to sync a single file system, instead of all
mounted file systems via sync(2):

 - On machines with many mounts, it is not at all uncommon for some of
   them to hang (e.g. unresponsive NFS server).  sync(2) will get stuck on
   those and may never get to the one you do care about (e.g., /).
 - Some applications write lots of data to the file system and then
   want to make sure it is flushed to disk.  Calling fsync(2) on each
   file introduces unnecessary ordering constraints that result in a large
   amount of sub-optimal writeback/flush/commit behavior by the file
   system.

There are currently two ways (that I know of) to sync a single super_block:

 - BLKFLSBUF ioctl on the block device: That also invalidates the bdev
   mapping, which isn't usually desirable, and doesn't work for non-block
   file systems.
 - 'mount -o remount,rw' will call sync_filesystem as an artifact of the
   current implemention.  Relying on this little-known side effect for
   something like data safety sounds foolish.

Both of these approaches require root privileges, which some applications
do not have (nor should they need?) given that sync(2) is an unprivileged
operation.

This patch introduces a new system call syncfs(2) that takes an fd and
syncs only the file system it references.  Maybe someday we can

 $ sync /some/path

and not get

 sync: ignoring all arguments

The syscall is motivated by comments by Al and Christoph at the last LSF.
syncfs(2) seems like an appropriate name given statfs(2).

A similar ioctl was also proposed a while back, see
	http://marc.info/?l=linux-fsdevel&m=127970513829285&w=2Signed-off-by: NSage Weil <sage@newdream.net>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      b7ed78f5
    • M
      powerpc/ptrace: Remove BUG_ON when full register set not available · a71f5d5d
      由 Mike Wolf 提交于 
      In some cases during a threaded core dump not all the threads will have
a full register set. This happens when the signal causing the core dump
races with a thread exiting.  The race happens when the exiting thread
has entered the kernel for the last time before the signal arrives, but
doesn't get far enough through the exit code to avoid being included
in the core dump.

So we get a thread included in the core dump which is never going to go
out to userspace again and only has a partial register set recorded

Normally we would catch each thread as it is about to go into userspace
and capture the full register set then.

However, this exiting thread is never going to go out to userspace
again, so we have no way to capture its full register set.  It doesn't
really matter, though, as this is a thread which is effectively
already dead.

So instead of hitting a BUG() in this case (a really bad choice of
action in the first place), we use a poison value for the register
values.

[BenH]: Some cosmetic/stylistic changes and fix build on ppc32
Signed-off-by: NMike Wolf <mjw@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
      a71f5d5d
    • M
      powerpc: Factoring mpic cpu id fetching into a function · d6a2639b
      由 Meador Inge 提交于 
      The following code snippet:

	unsigned int cpu = 0;
	if (mpic->flags & MPIC_PRIMARY)
		cpu = hard_smp_processor_id();

is seen in several places in the 'mpic.c' code.  This changeset factors
that pattern out into a helper function called 'mpic_processor_id'.
Signed-off-by: NMeador Inge <meador_inge@mentor.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
      d6a2639b
    • M
      powerpc: Make MPIC honor the "pic-no-reset" device tree property · dfec2202
      由 Meador Inge 提交于 
      This property, defined in the Open PIC binding, tells the kernel not to use
the reset bit in the global configuration register.  Additionally, its
presence mandates that only sources which are actually used (i.e. appear in
the device tree) should have their VECPRI bits initialized.

Although, "pic-no-reset" can be used for the same use cases that
"protected-sources" is covering, the "protected-sources" implementation was
left completely intact.  This is a more pragmatic approach as there are
already several existing systems which use protected sources.  If
"pic-no-reset" *and* "protected-sources" are both used, however, then
"pic-no-reset" takes precedence in terms of the init behavior and the
sanity checks done by protected sources will still take place.
Signed-off-by: NMeador Inge <meador_inge@mentor.com>
Cc: Hollis Blanchard <hollis_blanchard@mentor.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
      dfec2202
    • B
      powerpc/pci: Fix crash in PCI code on ppc64 when matching device nodes · 90407c99
      由 Benjamin Herrenschmidt 提交于 
      Commit b5d937de has a bug which causes
basically a NULL dereference in the PCI code during boot on ppc64
machines.

fetch_dev_dn() is called when dev->dev.of_node is NULL, so using that
as the starting point for the search makes no sense. It should instead
start from the device node of the PHB.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
      90407c99
  5. 20 3月, 2011 1 次提交
  7. 19 3月, 2011 18 次提交
  9. 18 3月, 2011 15 次提交