fs: Mark alloc_fd with EXPORT_SYMBOL

mark alloc_fd with EXPORT_SYMBOL so it can be used by modules.

Change-Id: Ic0dedbadecd2d0937cad8268aaa6eabbc52019ff
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
fs: fat: rate limit the kernel messages

If FAT formatted SD card gets removed without unmounting,
FAT file system may throw many kernel error messages which
could too much traffic for console driver and can sometimes
even cause the system to trigger watchdog timeout.

This patch converts the printk to printk_ratelimited to rate
limit the error messages from FAT fs.

Change-Id: I58b942f6714a8d3353478eb21139b8046ee3f875
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
(cherry picked from commit a872b71069d717ced1a2de642afa0693d1bb9448)
fs: yaffs: Use deferable timer for background operations

Use deferable timer in background operations thread,
so that it won't cause unnecessary wakeups. Typically,
wakeups are seen in the range 60ms to 2secs (for HZ=100)
after the thread is scheduled out. In general, during this
delay the processor can go into sleep, if there is no other
activity. Since, the work done in this background operation
is not critical and can be handled as soon as when timer
expires and processor wakes up for other critical events,
we mark the timer responsible for wakeup of this thread
as deferable timer. Otherwise, the processor wakesup
unnecessarily to handle the background operations causing
higher power consumption in idle state.

Change-Id: Ic168525c6b33600ad23017d00ea9723cf8a738d2
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
(cherry picked from commit 4e239c0cbfc9070ff0c006a92eaafd52243b47a0)
yaffs: add interface to cleancache

Cleancache requires a small amount of code to be added
to a filesystem's implementation so that clean page
cache pages from a filesystem of that type may be
recognized and stored in/retrieved from cleancache.

Change-Id: I94c3fc8817ab66e2c54f7b2c6c474dd2321d9806
Signed-off-by: Larry Bassel <lbassel@codeaurora.org>
(cherry picked from commit eb93161d9746b2aa0ac534d1da88a33480d21905)
proc: show present cpu instead of online cpu in /proc/stat

Some userspace applications use /proc/stat to determine how many CPUs
the system has. CPU hotplug can offline a CPU at runtime and causing the
offline CPU not present in /proc/stat if we only show online cpu in
/proc/stat.

Change-Id: I4fd0cfcdb174244044634389da2fbdef77744c19
Signed-off-by: Ajay Dudani <adudani@codeaurora.org>
yaffs2: Update for kernel 3.4

Update yaffs2 for newer kernel constructs and the removal of the
big kernel lock.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>