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authorDanilo Krummrich <dakr@kernel.org>2026-08-13 18:52:04 +0200
committerDanilo Krummrich <dakr@kernel.org>2026-08-17 01:41:36 +0200
commitf146c7bc85a51f95c05e0f8173d484eb301ece78 (patch)
tree07296ae54ed6551492b0c609dc0f5463f61f89ca /arch/arm/lib/putuser.S
downloadlinux-stable-f146c7bc85a51f95c05e0f8173d484eb301ece78.tar.gz
linux-stable-f146c7bc85a51f95c05e0f8173d484eb301ece78.zip
PCI: Add pci_irq_type() to query the allocated interrupt typegrafted
Add a helper that returns PCI_IRQ_MSIX, PCI_IRQ_MSI, or PCI_IRQ_INTX based on the interrupt type the PCI core selected after pci_alloc_irq_vectors(). Several drivers already open-code this check against pdev->msix_enabled and pdev->msi_enabled, or even open code this helper [1]. A common helper avoids the duplication and keeps drivers from accessing the bitfield directly (see also [2]). Acked-by: Bjorn Helgaas <bhelgaas@google.com> Tested-by: John Hubbard <jhubbard@nvidia.com> Link: https://elixir.bootlin.com/linux/v7.1/source/drivers/net/ethernet/aquantia/atlantic/aq_pci_func.c#L196 [1] Inspired-by: John Hubbard <jhubbard@nvidia.com> Link: https://lore.kernel.org/all/DKKG2QM3YJYB.Z2H2B2UXJ75N@kernel.org/ [2] Reviewed-by: Gary Guo <gary@garyguo.net> Link: https://patch.msgid.link/20260813165234.620555-5-dakr@kernel.org [ Add missing pci_irq_type() stub for CONFIG_PCI=n. ] Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Diffstat (limited to 'arch/arm/lib/putuser.S')
-rw-r--r--arch/arm/lib/putuser.S95
1 files changed, 95 insertions, 0 deletions
diff --git a/arch/arm/lib/putuser.S b/arch/arm/lib/putuser.S
new file mode 100644
index 000000000..bdd8836dc
--- /dev/null
+++ b/arch/arm/lib/putuser.S
@@ -0,0 +1,95 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * linux/arch/arm/lib/putuser.S
+ *
+ * Copyright (C) 2001 Russell King
+ *
+ * Idea from x86 version, (C) Copyright 1998 Linus Torvalds
+ *
+ * These functions have a non-standard call interface to make
+ * them more efficient, especially as they return an error
+ * value in addition to the "real" return value.
+ *
+ * __put_user_X
+ *
+ * Inputs: r0 contains the address
+ * r1 contains the address limit, which must be preserved
+ * r2, r3 contains the value
+ * Outputs: r0 is the error code
+ * lr corrupted
+ *
+ * No other registers must be altered. (see <asm/uaccess.h>
+ * for specific ASM register usage).
+ *
+ * Note that ADDR_LIMIT is either 0 or 0xc0000000
+ * Note also that it is intended that __put_user_bad is not global.
+ */
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <asm/errno.h>
+#include <asm/domain.h>
+
+ENTRY(__put_user_1)
+ check_uaccess r0, 1, r1, ip, __put_user_bad
+1: TUSER(strb) r2, [r0]
+ mov r0, #0
+ ret lr
+ENDPROC(__put_user_1)
+
+ENTRY(__put_user_2)
+ check_uaccess r0, 2, r1, ip, __put_user_bad
+#if __LINUX_ARM_ARCH__ >= 6
+
+2: TUSER(strh) r2, [r0]
+
+#else
+
+ mov ip, r2, lsr #8
+#ifndef __ARMEB__
+2: TUSER(strb) r2, [r0], #1
+3: TUSER(strb) ip, [r0]
+#else
+2: TUSER(strb) ip, [r0], #1
+3: TUSER(strb) r2, [r0]
+#endif
+
+#endif /* __LINUX_ARM_ARCH__ >= 6 */
+ mov r0, #0
+ ret lr
+ENDPROC(__put_user_2)
+
+ENTRY(__put_user_4)
+ check_uaccess r0, 4, r1, ip, __put_user_bad
+4: TUSER(str) r2, [r0]
+ mov r0, #0
+ ret lr
+ENDPROC(__put_user_4)
+
+ENTRY(__put_user_8)
+ check_uaccess r0, 8, r1, ip, __put_user_bad
+#ifdef CONFIG_THUMB2_KERNEL
+5: TUSER(str) r2, [r0]
+6: TUSER(str) r3, [r0, #4]
+#else
+5: TUSER(str) r2, [r0], #4
+6: TUSER(str) r3, [r0]
+#endif
+ mov r0, #0
+ ret lr
+ENDPROC(__put_user_8)
+
+__put_user_bad:
+ mov r0, #-EFAULT
+ ret lr
+ENDPROC(__put_user_bad)
+
+.pushsection __ex_table, "a"
+ .long 1b, __put_user_bad
+ .long 2b, __put_user_bad
+#if __LINUX_ARM_ARCH__ < 6
+ .long 3b, __put_user_bad
+#endif
+ .long 4b, __put_user_bad
+ .long 5b, __put_user_bad
+ .long 6b, __put_user_bad
+.popsection