The patch titled
Subject: xz: add ARM64 BCJ filter
has been added to the -mm mm-nonmm-unstable branch. Its filename is
xz-add-arm64-bcj-filter.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/xz-add-arm64-bcj-filter.patch
This patch will later appear in the mm-nonmm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Lasse Collin <lasse.collin@xxxxxxxxxxx>
Subject: xz: add ARM64 BCJ filter
Date: Wed, 20 Mar 2024 20:38:41 +0200
Also omit a duplicated check for XZ_DEC_ARM in xz_private.h.
This filter can be used by Squashfs without modifications to the Squashfs
kernel code (only needs support in userspace Squashfs-tools).
Link: https://lkml.kernel.org/r/20240320183846.19475-9-lasse.collin@xxxxxxxxxxx
Signed-off-by: Lasse Collin <lasse.collin@xxxxxxxxxxx>
Reviewed-by: Jia Tan <jiat0218@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
lib/xz/Kconfig | 5 ++++
lib/xz/xz_dec_bcj.c | 52 +++++++++++++++++++++++++++++++++++++++++-
lib/xz/xz_private.h | 7 ++++-
3 files changed, 61 insertions(+), 3 deletions(-)
--- a/lib/xz/Kconfig~xz-add-arm64-bcj-filter
+++ a/lib/xz/Kconfig
@@ -30,6 +30,11 @@ config XZ_DEC_ARMTHUMB
default y
select XZ_DEC_BCJ
+config XZ_DEC_ARM64
+ bool "ARM64 BCJ filter decoder" if EXPERT
+ default y
+ select XZ_DEC_BCJ
+
config XZ_DEC_SPARC
bool "SPARC BCJ filter decoder" if EXPERT
default y
--- a/lib/xz/xz_dec_bcj.c~xz-add-arm64-bcj-filter
+++ a/lib/xz/xz_dec_bcj.c
@@ -23,7 +23,8 @@ struct xz_dec_bcj {
BCJ_IA64 = 6, /* Big or little endian */
BCJ_ARM = 7, /* Little endian only */
BCJ_ARMTHUMB = 8, /* Little endian only */
- BCJ_SPARC = 9 /* Big or little endian */
+ BCJ_SPARC = 9, /* Big or little endian */
+ BCJ_ARM64 = 10 /* AArch64 */
} type;
/*
@@ -346,6 +347,47 @@ static size_t bcj_sparc(struct xz_dec_bc
}
#endif
+#ifdef XZ_DEC_ARM64
+static size_t bcj_arm64(struct xz_dec_bcj *s, uint8_t *buf, size_t size)
+{
+ size_t i;
+ uint32_t instr;
+ uint32_t addr;
+
+ size &= ~(size_t)3;
+
+ for (i = 0; i < size; i += 4) {
+ instr = get_unaligned_le32(buf + i);
+
+ if ((instr >> 26) == 0x25) {
+ /* BL instruction */
+ addr = instr - ((s->pos + (uint32_t)i) >> 2);
+ instr = 0x94000000 | (addr & 0x03FFFFFF);
+ put_unaligned_le32(instr, buf + i);
+
+ } else if ((instr & 0x9F000000) == 0x90000000) {
+ /* ADRP instruction */
+ addr = ((instr >> 29) & 3) | ((instr >> 3) & 0x1FFFFC);
+
+ /* Only convert values in the range +/-512 MiB. */
+ if ((addr + 0x020000) & 0x1C0000)
+ continue;
+
+ addr -= (s->pos + (uint32_t)i) >> 12;
+
+ instr &= 0x9000001F;
+ instr |= (addr & 3) << 29;
+ instr |= (addr & 0x03FFFC) << 3;
+ instr |= (0U - (addr & 0x020000)) & 0xE00000;
+
+ put_unaligned_le32(instr, buf + i);
+ }
+ }
+
+ return i;
+}
+#endif
+
/*
* Apply the selected BCJ filter. Update *pos and s->pos to match the amount
* of data that got filtered.
@@ -393,6 +435,11 @@ static void bcj_apply(struct xz_dec_bcj
filtered = bcj_sparc(s, buf, size);
break;
#endif
+#ifdef XZ_DEC_ARM64
+ case BCJ_ARM64:
+ filtered = bcj_arm64(s, buf, size);
+ break;
+#endif
default:
/* Never reached but silence compiler warnings. */
filtered = 0;
@@ -566,6 +613,9 @@ XZ_EXTERN enum xz_ret xz_dec_bcj_reset(s
#ifdef XZ_DEC_SPARC
case BCJ_SPARC:
#endif
+#ifdef XZ_DEC_ARM64
+ case BCJ_ARM64:
+#endif
break;
default:
--- a/lib/xz/xz_private.h~xz-add-arm64-bcj-filter
+++ a/lib/xz/xz_private.h
@@ -36,6 +36,9 @@
# ifdef CONFIG_XZ_DEC_SPARC
# define XZ_DEC_SPARC
# endif
+# ifdef CONFIG_XZ_DEC_ARM64
+# define XZ_DEC_ARM64
+# endif
# ifdef CONFIG_XZ_DEC_MICROLZMA
# define XZ_DEC_MICROLZMA
# endif
@@ -97,9 +100,9 @@
*/
#ifndef XZ_DEC_BCJ
# if defined(XZ_DEC_X86) || defined(XZ_DEC_POWERPC) \
- || defined(XZ_DEC_IA64) || defined(XZ_DEC_ARM) \
+ || defined(XZ_DEC_IA64) \
|| defined(XZ_DEC_ARM) || defined(XZ_DEC_ARMTHUMB) \
- || defined(XZ_DEC_SPARC)
+ || defined(XZ_DEC_SPARC) || defined(XZ_DEC_ARM64)
# define XZ_DEC_BCJ
# endif
#endif
_
Patches currently in -mm which might be from lasse.collin@xxxxxxxxxxx are
maintainers-add-xz-embedded-maintainers.patch
licenses-add-0bsd-license-text.patch
xz-switch-from-public-domain-to-bsd-zero-clause-license-0bsd.patch
xz-documentation-staging-xzrst-revise-thoroughly.patch
xz-fix-comments-and-coding-style.patch
xz-cleanup-crc32-edits-from-2018.patch
xz-optimize-for-loop-conditions-in-the-bcj-decoders.patch
xz-add-arm64-bcj-filter.patch
xz-add-risc-v-bcj-filter.patch
xz-use-128-mib-dictionary-and-force-single-threaded-mode.patch
xz-adjust-arch-specific-options-for-better-kernel-compression.patch
