UPSTREAM: zram: pass gfp from zcomp frontend to backend

(cherry picked from commit 75d8947a36d0c9aedd69118d1f14bf424005c7c2)

Each zcomp backend uses own gfp flag but it's pointless because the
context they could be called is driven by upper layer(ie, zcomp
frontend).  As well, zcomp frondend could call them in different
context.  One context(ie, zram init part) is it should be better to make
sure successful allocation other context(ie, further stream allocation
part for accelarating I/O speed) is just optional so let's pass gfp down
from driver (ie, zcomp frontend) like normal MM convention.

[sergey.senozhatsky@gmail.com: add missing __vmalloc zero and highmem gfps]
Signed-off-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

4 files changed, 23 insertions, 34 deletions

diff --git a/drivers/block/zram/zcomp.c b/drivers/block/zram/zcomp.c
index 4eb2e9a70..ba800660c 100644
--- a/drivers/block/zram/zcomp.c
+++ b/drivers/block/zram/zcomp.c
@@ -74,18 +74,18 @@ static void zcomp_strm_free(struct zcomp *comp, struct zcomp_strm *zstrm)
  * allocate new zcomp_strm structure with ->private initialized by
  * backend, return NULL on error
  */
-static struct zcomp_strm *zcomp_strm_alloc(struct zcomp *comp)
+static struct zcomp_strm *zcomp_strm_alloc(struct zcomp *comp, gfp_t flags)
 {
-	struct zcomp_strm *zstrm = kmalloc(sizeof(*zstrm), GFP_NOIO);
+	struct zcomp_strm *zstrm = kmalloc(sizeof(*zstrm), flags);
 	if (!zstrm)
 		return NULL;
 
-	zstrm->private = comp->backend->create();
+	zstrm->private = comp->backend->create(flags);
 	/*
 	 * allocate 2 pages. 1 for compressed data, plus 1 extra for the
 	 * case when compressed size is larger than the original one
 	 */
-	zstrm->buffer = (void *)__get_free_pages(GFP_NOIO | __GFP_ZERO, 1);
+	zstrm->buffer = (void *)__get_free_pages(flags | __GFP_ZERO, 1);
 	if (!zstrm->private || !zstrm->buffer) {
 		zcomp_strm_free(comp, zstrm);
 		zstrm = NULL;
@@ -121,7 +121,16 @@ static struct zcomp_strm *zcomp_strm_multi_find(struct zcomp *comp)
 		zs->avail_strm++;
 		spin_unlock(&zs->strm_lock);
 
-		zstrm = zcomp_strm_alloc(comp);
+        /*
+         * This function can be called in swapout/fs write path
+         * so we can't use GFP_FS|IO. And it assumes we already
+         * have at least one stream in zram initialization so we
+         * don't do best effort to allocate more stream in here.
+         * A default stream will work well without further multiple
+         * streams. That's why we use NORETRY | NOWARN.
+         */
+        zstrm = zcomp_strm_alloc(comp, GFP_NOIO | __GFP_NORETRY |
+                   __GFP_NOWARN);
 		if (!zstrm) {
 			spin_lock(&zs->strm_lock);
 			zs->avail_strm--;
@@ -209,7 +218,7 @@ static int zcomp_strm_multi_create(struct zcomp *comp, int max_strm)
 	zs->max_strm = max_strm;
 	zs->avail_strm = 1;
 
-	zstrm = zcomp_strm_alloc(comp);
+	zstrm = zcomp_strm_alloc(comp, GFP_KERNEL);
 	if (!zstrm) {
 		kfree(zs);
 		return -ENOMEM;
@@ -259,7 +268,7 @@ static int zcomp_strm_single_create(struct zcomp *comp)
 
 	comp->stream = zs;
 	mutex_init(&zs->strm_lock);
-	zs->zstrm = zcomp_strm_alloc(comp);
+	zs->zstrm = zcomp_strm_alloc(comp, GFP_KERNEL);
 	if (!zs->zstrm) {
 		kfree(zs);
 		return -ENOMEM;
diff --git a/drivers/block/zram/zcomp_lz4.c b/drivers/block/zram/zcomp_lz4.c
index 6f95755c3..1b4cff653 100644
--- a/drivers/block/zram/zcomp_lz4.c
+++ b/drivers/block/zram/zcomp_lz4.c
@@ -15,24 +15,14 @@
 
 #include "zcomp_lz4.h"
 
-static void *zcomp_lz4_create(void)
+static void *zcomp_lz4_create(gfp_t flags)
 {
 	void *ret;
 
-	/*
-	 * This function can be called in swapout/fs write path
-	 * so we can't use GFP_FS|IO. And it assumes we already
-	 * have at least one stream in zram initialization so we
-	 * don't do best effort to allocate more stream in here.
-	 * A default stream will work well without further multiple
-	 * streams. That's why we use NORETRY | NOWARN.
-	 */
-	ret = kzalloc(LZ4_MEM_COMPRESS, GFP_NOIO | __GFP_NORETRY |
-					__GFP_NOWARN);
+    ret = kzalloc(LZ4_MEM_COMPRESS, flags);
 	if (!ret)
 		ret = __vmalloc(LZ4_MEM_COMPRESS,
-				GFP_NOIO | __GFP_NORETRY | __GFP_NOWARN |
-				__GFP_ZERO | __GFP_HIGHMEM,
+                flags | __GFP_ZERO | __GFP_HIGHMEM,
 				PAGE_KERNEL);
 	return ret;
 }
diff --git a/drivers/block/zram/zcomp_lzo.c b/drivers/block/zram/zcomp_lzo.c
index edc549920..53c52295c 100644
--- a/drivers/block/zram/zcomp_lzo.c
+++ b/drivers/block/zram/zcomp_lzo.c
@@ -15,24 +15,14 @@
 
 #include "zcomp_lzo.h"
 
-static void *lzo_create(void)
+static void *lzo_create(gfp_t flags)
 {
 	void *ret;
 
-	/*
-	 * This function can be called in swapout/fs write path
-	 * so we can't use GFP_FS|IO. And it assumes we already
-	 * have at least one stream in zram initialization so we
-	 * don't do best effort to allocate more stream in here.
-	 * A default stream will work well without further multiple
-	 * streams. That's why we use NORETRY | NOWARN.
-	 */
-	ret = kzalloc(LZO1X_MEM_COMPRESS, GFP_NOIO | __GFP_NORETRY |
-					__GFP_NOWARN);
+    ret = kzalloc(LZO1X_MEM_COMPRESS, flags);
 	if (!ret)
 		ret = __vmalloc(LZO1X_MEM_COMPRESS,
-				GFP_NOIO | __GFP_NORETRY | __GFP_NOWARN |
-				__GFP_ZERO | __GFP_HIGHMEM,
+                flags | __GFP_ZERO | __GFP_HIGHMEM,
 				PAGE_KERNEL);
 	return ret;
 }
diff --git a/include/linux/zcomp.h b/include/linux/zcomp.h
index c59d1fca7..5fb9769a3 100644
--- a/include/linux/zcomp.h
+++ b/include/linux/zcomp.h
@@ -33,7 +33,7 @@ struct zcomp_backend {
 	int (*decompress)(const unsigned char *src, size_t src_len,
 			unsigned char *dst);
 
-	void *(*create)(void);
+    void *(*create)(gfp_t flags);
 	void (*destroy)(void *private);
 
 	const char *name;