coccinelle: mm: scripts/coccinelle/api/alloc/pool_zalloc-simple.cocci

add [pci|dma]_pool_zalloc coccinelle check.
replaces instances of [pci|dma]_pool_alloc() followed by memset(0)
with [pci|dma]_pool_zalloc().
Signed-off-by: NSean O. Stalley <sean.stalley@intel.com>
Acked-by: NJulia Lawall <julia.lawall@lip6.fr>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Gilles Muller <Gilles.Muller@lip6.fr>
Cc: Nicolas Palix <nicolas.palix@imag.fr>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

scripts/coccinelle/api/alloc/pool_zalloc-simple.cocci

+///
+/// Use *_pool_zalloc rather than *_pool_alloc followed by memset with 0
+///
+// Copyright: (C) 2015 Intel Corp.  GPLv2.
+// Options: --no-includes --include-headers
+//
+// Keywords: dma_pool_zalloc, pci_pool_zalloc
+//
+
+virtual context
+virtual patch
+virtual org
+virtual report
+
+//----------------------------------------------------------
+//  For context mode
+//----------------------------------------------------------
+
+@depends on context@
+expression x;
+statement S;
+@@
+
+* x = \(dma_pool_alloc\|pci_pool_alloc\)(...);
+  if ((x==NULL) || ...) S
+* memset(x,0, ...);
+
+//----------------------------------------------------------
+//  For patch mode
+//----------------------------------------------------------
+
+@depends on patch@
+expression x;
+expression a,b,c;
+statement S;
+@@
+
+- x = dma_pool_alloc(a,b,c);
++ x = dma_pool_zalloc(a,b,c);
+  if ((x==NULL) || ...) S
+- memset(x,0,...);
+
+@depends on patch@
+expression x;
+expression a,b,c;
+statement S;
+@@
+
+- x = pci_pool_alloc(a,b,c);
++ x = pci_pool_zalloc(a,b,c);
+  if ((x==NULL) || ...) S
+- memset(x,0,...);
+
+//----------------------------------------------------------
+//  For org and report mode
+//----------------------------------------------------------
+
+@r depends on org || report@
+expression x;
+expression a,b,c;
+statement S;
+position p;
+@@
+
+ x = @p\(dma_pool_alloc\|pci_pool_alloc\)(a,b,c);
+ if ((x==NULL) || ...) S
+ memset(x,0, ...);
+
+@script:python depends on org@
+p << r.p;
+x << r.x;
+@@
+
+msg="%s" % (x)
+msg_safe=msg.replace("[","@(").replace("]",")")
+coccilib.org.print_todo(p[0], msg_safe)
+
+@script:python depends on report@
+p << r.p;
+x << r.x;
+@@
+
+msg="WARNING: *_pool_zalloc should be used for %s, instead of *_pool_alloc/memset" % (x)
+coccilib.report.print_report(p[0], msg)