summaryrefslogtreecommitdiffstats
path: root/arch/arm64/lib/mte.S
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
commitf4cdf7ca9a1fdcca413157df19753f388a5a224e (patch)
tree60a31895b2446cd7fa27514e8c2843534a0de0da /arch/arm64/lib/mte.S
downloadlinux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.tar.gz
linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.zip
Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab: - v4l2-core: added ISP statistics support and per-block validation - v4l2-core: Allow unknown HDR10 white point and luminance - New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor - New codec: Milos: VPU v2.0 codec support - isp driver: gained support for Dreamchip RPPX1 ISP framework - vsp1 driver: gained support for RZ/T2H and RZ/N2H - Novalake driver: gained CVS support for new NVL hardware - dvb-core: fix feed leak on failed DMX_ADD_PID - several driver fixes, cleanups and minor improvements * tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits) media: ipu-bridge: check all DMI entries when overriding sensor rotation media: v4l2-async: avoid deleting unlinked ASC entry on link error media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement media: intel/ipu6: fix async notifier cleanup leak on parse error media: staging/ipu7: fix async notifier UAF on probe error path media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem() media: rcar-isp: Fix VSPX reference leaks media: rcar-isp: Release ISPCORE resources media: i2c: imx415: Release runtime PM reference on VBLANK error media: i2c: imx415: Return test pattern write errors media: renesas: vsp1: Declare index variables in for loop statement media: renesas: vsp1: Make reset control optional to support platforms without a reset line media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs media: nxp: imx8-isi: Add additional 32-bit RGB format support media: nxp: imx8-isi: Add 16-bit raw Bayer format support media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks media: nxp: imx8-isi: Correct color map between V4L2 and ISI ...
Diffstat (limited to 'arch/arm64/lib/mte.S')
-rw-r--r--arch/arm64/lib/mte.S177
1 files changed, 177 insertions, 0 deletions
diff --git a/arch/arm64/lib/mte.S b/arch/arm64/lib/mte.S
new file mode 100644
index 000000000..5018ac03b
--- /dev/null
+++ b/arch/arm64/lib/mte.S
@@ -0,0 +1,177 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2020 ARM Ltd.
+ */
+#include <linux/linkage.h>
+
+#include <asm/asm-uaccess.h>
+#include <asm/assembler.h>
+#include <asm/mte.h>
+#include <asm/page.h>
+#include <asm/sysreg.h>
+
+ .arch armv8.5-a+memtag
+
+/*
+ * multitag_transfer_size - set \reg to the block size that is accessed by the
+ * LDGM/STGM instructions.
+ */
+ .macro multitag_transfer_size, reg, tmp
+ mrs_s \reg, SYS_GMID_EL1
+ ubfx \reg, \reg, #GMID_EL1_BS_SHIFT, #GMID_EL1_BS_WIDTH
+ mov \tmp, #4
+ lsl \reg, \tmp, \reg
+ .endm
+
+/*
+ * Clear the tags in a page
+ * x0 - address of the page to be cleared
+ */
+SYM_FUNC_START(mte_clear_page_tags)
+ multitag_transfer_size x1, x2
+1: stgm xzr, [x0]
+ add x0, x0, x1
+ tst x0, #(PAGE_SIZE - 1)
+ b.ne 1b
+ ret
+SYM_FUNC_END(mte_clear_page_tags)
+
+/*
+ * Zero the page and tags at the same time
+ *
+ * Parameters:
+ * x0 - address to the beginning of the page
+ */
+SYM_FUNC_START(mte_zero_clear_page_tags)
+ and x0, x0, #(1 << MTE_TAG_SHIFT) - 1 // clear the tag
+ mrs x1, dczid_el0
+ tbnz x1, #4, 2f // Branch if DC GZVA is prohibited
+ and w1, w1, #0xf
+ mov x2, #4
+ lsl x1, x2, x1
+
+1: dc gzva, x0
+ add x0, x0, x1
+ tst x0, #(PAGE_SIZE - 1)
+ b.ne 1b
+ ret
+
+2: stz2g x0, [x0], #(MTE_GRANULE_SIZE * 2)
+ tst x0, #(PAGE_SIZE - 1)
+ b.ne 2b
+ ret
+SYM_FUNC_END(mte_zero_clear_page_tags)
+
+/*
+ * Copy the tags from the source page to the destination one
+ * x0 - address of the destination page
+ * x1 - address of the source page
+ */
+SYM_FUNC_START(mte_copy_page_tags)
+ mov x2, x0
+ mov x3, x1
+ multitag_transfer_size x5, x6
+1: ldgm x4, [x3]
+ stgm x4, [x2]
+ add x2, x2, x5
+ add x3, x3, x5
+ tst x2, #(PAGE_SIZE - 1)
+ b.ne 1b
+ ret
+SYM_FUNC_END(mte_copy_page_tags)
+
+/*
+ * Read tags from a user buffer (one tag per byte) and set the corresponding
+ * tags at the given kernel address. Used by PTRACE_POKEMTETAGS.
+ * x0 - kernel address (to)
+ * x1 - user buffer (from)
+ * x2 - number of tags/bytes (n)
+ * Returns:
+ * x0 - number of tags read/set
+ */
+SYM_FUNC_START(mte_copy_tags_from_user)
+ mov x3, x1
+ cbz x2, 2f
+1:
+USER(2f, ldtrb w4, [x1])
+ lsl x4, x4, #MTE_TAG_SHIFT
+ stg x4, [x0], #MTE_GRANULE_SIZE
+ add x1, x1, #1
+ subs x2, x2, #1
+ b.ne 1b
+
+ // exception handling and function return
+2: sub x0, x1, x3 // update the number of tags set
+ ret
+SYM_FUNC_END(mte_copy_tags_from_user)
+
+/*
+ * Get the tags from a kernel address range and write the tag values to the
+ * given user buffer (one tag per byte). Used by PTRACE_PEEKMTETAGS.
+ * x0 - user buffer (to)
+ * x1 - kernel address (from)
+ * x2 - number of tags/bytes (n)
+ * Returns:
+ * x0 - number of tags read/set
+ */
+SYM_FUNC_START(mte_copy_tags_to_user)
+ mov x3, x0
+ cbz x2, 2f
+1:
+ ldg x4, [x1]
+ ubfx x4, x4, #MTE_TAG_SHIFT, #MTE_TAG_SIZE
+USER(2f, sttrb w4, [x0])
+ add x0, x0, #1
+ add x1, x1, #MTE_GRANULE_SIZE
+ subs x2, x2, #1
+ b.ne 1b
+
+ // exception handling and function return
+2: sub x0, x0, x3 // update the number of tags copied
+ ret
+SYM_FUNC_END(mte_copy_tags_to_user)
+
+/*
+ * Save the tags in a page
+ * x0 - page address
+ * x1 - tag storage, MTE_PAGE_TAG_STORAGE bytes
+ */
+SYM_FUNC_START(mte_save_page_tags)
+ multitag_transfer_size x7, x5
+1:
+ mov x2, #0
+2:
+ ldgm x5, [x0]
+ orr x2, x2, x5
+ add x0, x0, x7
+ tst x0, #0xFF // 16 tag values fit in a register,
+ b.ne 2b // which is 16*16=256 bytes
+
+ str x2, [x1], #8
+
+ tst x0, #(PAGE_SIZE - 1)
+ b.ne 1b
+
+ ret
+SYM_FUNC_END(mte_save_page_tags)
+
+/*
+ * Restore the tags in a page
+ * x0 - page address
+ * x1 - tag storage, MTE_PAGE_TAG_STORAGE bytes
+ */
+SYM_FUNC_START(mte_restore_page_tags)
+ multitag_transfer_size x7, x5
+1:
+ ldr x2, [x1], #8
+2:
+ stgm x2, [x0]
+ add x0, x0, x7
+ tst x0, #0xFF
+ b.ne 2b
+
+ tst x0, #(PAGE_SIZE - 1)
+ b.ne 1b
+
+ ret
+SYM_FUNC_END(mte_restore_page_tags)