From deaa7052c5161f54b42da0c887d08fddfa1130d7 Mon Sep 17 00:00:00 2001 From: Vladimir Serbinenko Date: Sat, 16 Nov 2013 16:03:28 +0100 Subject: [PATCH] Decrease stack usage in BtrFS. We have only 92K of stack and using over 4K per frame is wasteful * grub-core/fs/btrfs.c (grub_btrfs_lzo_decompress): Allocate on heap rather than stack. --- ChangeLog | 9 +++++++++ grub-core/fs/btrfs.c | 13 +++++++++++-- 2 files changed, 20 insertions(+), 2 deletions(-) diff --git a/ChangeLog b/ChangeLog index 3022acf6e..9e48e3932 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,12 @@ +2013-11-16 Vladimir Serbinenko + + Decrease stack usage in BtrFS. + + We have only 92K of stack and using over 4K per frame is wasteful + + * grub-core/fs/btrfs.c (grub_btrfs_lzo_decompress): Allocate on heap + rather than stack. + 2013-11-16 Vladimir Serbinenko Decrease stack usage in JFS. diff --git a/grub-core/fs/btrfs.c b/grub-core/fs/btrfs.c index 49f11cc3c..a60852756 100644 --- a/grub-core/fs/btrfs.c +++ b/grub-core/fs/btrfs.c @@ -911,7 +911,6 @@ grub_btrfs_lzo_decompress(char *ibuf, grub_size_t isize, grub_off_t off, { grub_uint32_t total_size, cblock_size; grub_size_t ret = 0; - unsigned char buf[GRUB_BTRFS_LZO_BLOCK_SIZE]; char *ibuf0 = ibuf; total_size = grub_le_to_cpu32 (grub_get_unaligned32 (ibuf)); @@ -955,13 +954,21 @@ grub_btrfs_lzo_decompress(char *ibuf, grub_size_t isize, grub_off_t off, if (off > 0 || osize < GRUB_BTRFS_LZO_BLOCK_SIZE) { grub_size_t to_copy = GRUB_BTRFS_LZO_BLOCK_SIZE - off; + grub_uint8_t *buf; if (to_copy > osize) to_copy = osize; + buf = grub_malloc (GRUB_BTRFS_LZO_BLOCK_SIZE); + if (!buf) + return -1; + if (lzo1x_decompress_safe ((lzo_bytep)ibuf, cblock_size, buf, &usize, NULL) != LZO_E_OK) - return -1; + { + grub_free (buf); + return -1; + } if (to_copy > usize) to_copy = usize; @@ -972,6 +979,8 @@ grub_btrfs_lzo_decompress(char *ibuf, grub_size_t isize, grub_off_t off, obuf += to_copy; ibuf += cblock_size; off = 0; + + grub_free (buf); continue; }