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linux-next/fs/jffs2/compr_zlib.c
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00

219 lines
5.7 KiB
C

/*
* JFFS2 -- Journalling Flash File System, Version 2.
*
* Copyright © 2001-2007 Red Hat, Inc.
*
* Created by David Woodhouse <dwmw2@infradead.org>
*
* For licensing information, see the file 'LICENCE' in this directory.
*
*/
#if !defined(__KERNEL__) && !defined(__ECOS)
#error "The userspace support got too messy and was removed. Update your mkfs.jffs2"
#endif
#include <linux/kernel.h>
#include <linux/zlib.h>
#include <linux/zutil.h>
#include "nodelist.h"
#include "compr.h"
/* Plan: call deflate() with avail_in == *sourcelen,
avail_out = *dstlen - 12 and flush == Z_FINISH.
If it doesn't manage to finish, call it again with
avail_in == 0 and avail_out set to the remaining 12
bytes for it to clean up.
Q: Is 12 bytes sufficient?
*/
#define STREAM_END_SPACE 12
static DEFINE_MUTEX(deflate_mutex);
static DEFINE_MUTEX(inflate_mutex);
static z_stream inf_strm, def_strm;
#ifdef __KERNEL__ /* Linux-only */
#include <linux/vmalloc.h>
#include <linux/init.h>
#include <linux/mutex.h>
static int __init alloc_workspaces(void)
{
def_strm.workspace = vmalloc(zlib_deflate_workspacesize());
if (!def_strm.workspace) {
printk(KERN_WARNING "Failed to allocate %d bytes for deflate workspace\n", zlib_deflate_workspacesize());
return -ENOMEM;
}
D1(printk(KERN_DEBUG "Allocated %d bytes for deflate workspace\n", zlib_deflate_workspacesize()));
inf_strm.workspace = vmalloc(zlib_inflate_workspacesize());
if (!inf_strm.workspace) {
printk(KERN_WARNING "Failed to allocate %d bytes for inflate workspace\n", zlib_inflate_workspacesize());
vfree(def_strm.workspace);
return -ENOMEM;
}
D1(printk(KERN_DEBUG "Allocated %d bytes for inflate workspace\n", zlib_inflate_workspacesize()));
return 0;
}
static void free_workspaces(void)
{
vfree(def_strm.workspace);
vfree(inf_strm.workspace);
}
#else
#define alloc_workspaces() (0)
#define free_workspaces() do { } while(0)
#endif /* __KERNEL__ */
static int jffs2_zlib_compress(unsigned char *data_in,
unsigned char *cpage_out,
uint32_t *sourcelen, uint32_t *dstlen,
void *model)
{
int ret;
if (*dstlen <= STREAM_END_SPACE)
return -1;
mutex_lock(&deflate_mutex);
if (Z_OK != zlib_deflateInit(&def_strm, 3)) {
printk(KERN_WARNING "deflateInit failed\n");
mutex_unlock(&deflate_mutex);
return -1;
}
def_strm.next_in = data_in;
def_strm.total_in = 0;
def_strm.next_out = cpage_out;
def_strm.total_out = 0;
while (def_strm.total_out < *dstlen - STREAM_END_SPACE && def_strm.total_in < *sourcelen) {
def_strm.avail_out = *dstlen - (def_strm.total_out + STREAM_END_SPACE);
def_strm.avail_in = min((unsigned)(*sourcelen-def_strm.total_in), def_strm.avail_out);
D1(printk(KERN_DEBUG "calling deflate with avail_in %d, avail_out %d\n",
def_strm.avail_in, def_strm.avail_out));
ret = zlib_deflate(&def_strm, Z_PARTIAL_FLUSH);
D1(printk(KERN_DEBUG "deflate returned with avail_in %d, avail_out %d, total_in %ld, total_out %ld\n",
def_strm.avail_in, def_strm.avail_out, def_strm.total_in, def_strm.total_out));
if (ret != Z_OK) {
D1(printk(KERN_DEBUG "deflate in loop returned %d\n", ret));
zlib_deflateEnd(&def_strm);
mutex_unlock(&deflate_mutex);
return -1;
}
}
def_strm.avail_out += STREAM_END_SPACE;
def_strm.avail_in = 0;
ret = zlib_deflate(&def_strm, Z_FINISH);
zlib_deflateEnd(&def_strm);
if (ret != Z_STREAM_END) {
D1(printk(KERN_DEBUG "final deflate returned %d\n", ret));
ret = -1;
goto out;
}
if (def_strm.total_out >= def_strm.total_in) {
D1(printk(KERN_DEBUG "zlib compressed %ld bytes into %ld; failing\n",
def_strm.total_in, def_strm.total_out));
ret = -1;
goto out;
}
D1(printk(KERN_DEBUG "zlib compressed %ld bytes into %ld\n",
def_strm.total_in, def_strm.total_out));
*dstlen = def_strm.total_out;
*sourcelen = def_strm.total_in;
ret = 0;
out:
mutex_unlock(&deflate_mutex);
return ret;
}
static int jffs2_zlib_decompress(unsigned char *data_in,
unsigned char *cpage_out,
uint32_t srclen, uint32_t destlen,
void *model)
{
int ret;
int wbits = MAX_WBITS;
mutex_lock(&inflate_mutex);
inf_strm.next_in = data_in;
inf_strm.avail_in = srclen;
inf_strm.total_in = 0;
inf_strm.next_out = cpage_out;
inf_strm.avail_out = destlen;
inf_strm.total_out = 0;
/* If it's deflate, and it's got no preset dictionary, then
we can tell zlib to skip the adler32 check. */
if (srclen > 2 && !(data_in[1] & PRESET_DICT) &&
((data_in[0] & 0x0f) == Z_DEFLATED) &&
!(((data_in[0]<<8) + data_in[1]) % 31)) {
D2(printk(KERN_DEBUG "inflate skipping adler32\n"));
wbits = -((data_in[0] >> 4) + 8);
inf_strm.next_in += 2;
inf_strm.avail_in -= 2;
} else {
/* Let this remain D1 for now -- it should never happen */
D1(printk(KERN_DEBUG "inflate not skipping adler32\n"));
}
if (Z_OK != zlib_inflateInit2(&inf_strm, wbits)) {
printk(KERN_WARNING "inflateInit failed\n");
mutex_unlock(&inflate_mutex);
return 1;
}
while((ret = zlib_inflate(&inf_strm, Z_FINISH)) == Z_OK)
;
if (ret != Z_STREAM_END) {
printk(KERN_NOTICE "inflate returned %d\n", ret);
}
zlib_inflateEnd(&inf_strm);
mutex_unlock(&inflate_mutex);
return 0;
}
static struct jffs2_compressor jffs2_zlib_comp = {
.priority = JFFS2_ZLIB_PRIORITY,
.name = "zlib",
.compr = JFFS2_COMPR_ZLIB,
.compress = &jffs2_zlib_compress,
.decompress = &jffs2_zlib_decompress,
#ifdef JFFS2_ZLIB_DISABLED
.disabled = 1,
#else
.disabled = 0,
#endif
};
int __init jffs2_zlib_init(void)
{
int ret;
ret = alloc_workspaces();
if (ret)
return ret;
ret = jffs2_register_compressor(&jffs2_zlib_comp);
if (ret)
free_workspaces();
return ret;
}
void jffs2_zlib_exit(void)
{
jffs2_unregister_compressor(&jffs2_zlib_comp);
free_workspaces();
}