From 5a8d1f60b2505cf2ee116ac38e54e65b757a1773 Mon Sep 17 00:00:00 2001
From: Heinrich Schuchardt <xypron.glpk@gmx.de>
Date: Mon, 6 Jul 2020 07:48:14 +0200
Subject: [PATCH] fs/fat: reduce data size for FAT_WRITE
Allocated tmpbuf_cluster dynamically to reduce the data size added by
compiling with CONFIG_FAT_WRITE.
Reported-by: Tom Rini <trini@konsulko.com>
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
---
fs/fat/fat_write.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/fs/fat/fat_write.c b/fs/fat/fat_write.c
index b16a39d3ff..a2682b5f46 100644
--- a/fs/fat/fat_write.c
+++ b/fs/fat/fat_write.c
@@ -500,8 +500,6 @@ flush_dir(fat_itr *itr)
nsects * mydata->sect_size);
}
-static __u8 tmpbuf_cluster[MAX_CLUSTSIZE] __aligned(ARCH_DMA_MINALIGN);
-
/*
* Read and modify data on existing and consecutive cluster blocks
*/
@@ -509,6 +507,7 @@ static int
get_set_cluster(fsdata *mydata, __u32 clustnum, loff_t pos, __u8 *buffer,
loff_t size, loff_t *gotsize)
{
+ static u8 *tmpbuf_cluster;
unsigned int bytesperclust = mydata->clust_size * mydata->sect_size;
__u32 startsect;
loff_t wsize;
@@ -518,6 +517,12 @@ get_set_cluster(fsdata *mydata, __u32 clustnum, loff_t pos, __u8 *buffer,
if (!size)
return 0;
+ if (!tmpbuf_cluster) {
+ tmpbuf_cluster = memalign(ARCH_DMA_MINALIGN, MAX_CLUSTSIZE);
+ if (!tmpbuf_cluster)
+ return -1;
+ }
+
assert(pos < bytesperclust);
startsect = clust_to_sect(mydata, clustnum);
--
2.39.5