[PATCH 1/2] erofs-utils: support 64-bit internal buffer cache

[Gao Xiang via Linux-erofs <linux-erofs@lists.ozlabs.org>]

From: Gao Xiang <gaoxiang25@huawei.com>

Previously, the type of off in struct erofs_buffer_head
is unsigned int, it's not enough for large files.

Fix to a 64-bit field in order to support large files.

Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
---
Hi Guifu,
Please take some time to review these patches
since I'd like to release erofs-utils 1.0 recently.

Thanks,
Gao Xiang

 include/erofs/cache.h |  8 ++++----
 include/erofs/defs.h  |  4 ++++
 lib/cache.c           | 15 ++++++++-------
 3 files changed, 16 insertions(+), 11 deletions(-)

diff --git a/include/erofs/cache.h b/include/erofs/cache.h
index 71df811..10a6aac 100644
--- a/include/erofs/cache.h
+++ b/include/erofs/cache.h
@@ -31,7 +31,7 @@ struct erofs_buffer_head {
 	struct list_head list;
 	struct erofs_buffer_block *block;
 
-	unsigned int off;
+	erofs_off_t off;
 	struct erofs_bhops *op;
 
 	void *fsprivate;
@@ -87,13 +87,13 @@ static inline bool erofs_bh_flush_generic_end(struct erofs_buffer_head *bh)
 }
 
 struct erofs_buffer_head *erofs_buffer_init(void);
-int erofs_bh_balloon(struct erofs_buffer_head *bh, unsigned int incr);
+int erofs_bh_balloon(struct erofs_buffer_head *bh, erofs_off_t incr);
 
-struct erofs_buffer_head *erofs_balloc(int type, unsigned int size,
+struct erofs_buffer_head *erofs_balloc(int type, erofs_off_t size,
 				       unsigned int required_ext,
 				       unsigned int inline_ext);
 struct erofs_buffer_head *erofs_battach(struct erofs_buffer_head *bh,
-					int type, int size);
+					int type, unsigned int size);
 
 erofs_blk_t erofs_mapbh(struct erofs_buffer_block *bb, bool end);
 bool erofs_bflush(struct erofs_buffer_block *bb);
diff --git a/include/erofs/defs.h b/include/erofs/defs.h
index 0d9910c..15db4e3 100644
--- a/include/erofs/defs.h
+++ b/include/erofs/defs.h
@@ -136,6 +136,10 @@ typedef int64_t         s64;
 	type __max2 = (y);			\
 	__max1 > __max2 ? __max1: __max2; })
 
+#define sgn(x) ({		\
+	typeof(x) _x = (x);	\
+(_x > 0) - (_x < 0); })
+
 #define ARRAY_SIZE(arr)	(sizeof(arr) / sizeof((arr)[0]))
 
 #define BIT(nr)             (1UL << (nr))
diff --git a/lib/cache.c b/lib/cache.c
index 4f03cb9..41d2d5d 100644
--- a/lib/cache.c
+++ b/lib/cache.c
@@ -74,14 +74,15 @@ struct erofs_buffer_head *erofs_buffer_init(void)
 /* return occupied bytes in specific buffer block if succeed */
 static int __erofs_battach(struct erofs_buffer_block *bb,
 			   struct erofs_buffer_head *bh,
-			   unsigned int incr,
+			   erofs_off_t incr,
 			   unsigned int alignsize,
 			   unsigned int extrasize,
 			   bool dryrun)
 {
-	const unsigned int alignedoffset = roundup(bb->buffers.off, alignsize);
-	const int oob = alignedoffset + incr + extrasize -
-			roundup(bb->buffers.off + 1, EROFS_BLKSIZ);
+	const erofs_off_t alignedoffset = roundup(bb->buffers.off, alignsize);
+	const int oob = sgn(roundup(bb->buffers.off % EROFS_BLKSIZ,
+				    alignsize) + incr + extrasize -
+			    EROFS_BLKSIZ);
 	bool tailupdate = false;
 	erofs_blk_t blkaddr;
 
@@ -113,7 +114,7 @@ static int __erofs_battach(struct erofs_buffer_block *bb,
 	return (alignedoffset + incr) % EROFS_BLKSIZ;
 }
 
-int erofs_bh_balloon(struct erofs_buffer_head *bh, unsigned int incr)
+int erofs_bh_balloon(struct erofs_buffer_head *bh, erofs_off_t incr)
 {
 	struct erofs_buffer_block *const bb = bh->block;
 
@@ -124,7 +125,7 @@ int erofs_bh_balloon(struct erofs_buffer_head *bh, unsigned int incr)
 	return __erofs_battach(bb, NULL, incr, 1, 0, false);
 }
 
-struct erofs_buffer_head *erofs_balloc(int type, unsigned int size,
+struct erofs_buffer_head *erofs_balloc(int type, erofs_off_t size,
 				       unsigned int required_ext,
 				       unsigned int inline_ext)
 {
@@ -214,7 +215,7 @@ found:
 }
 
 struct erofs_buffer_head *erofs_battach(struct erofs_buffer_head *bh,
-					int type, int size)
+					int type, unsigned int size)
 {
 	struct erofs_buffer_block *const bb = bh->block;
 	struct erofs_buffer_head *nbh;
-- 
2.17.1