From: Florian Fainelli <f.fainelli@gmail.com>
Date: Thu, 7 Jul 2022 20:27:58 +0000 (-0700)
Subject: MIPS: vdso: Utilize __pa() for gic_pfn
X-Git-Tag: baikal/mips/sdk5.9~182
X-Git-Url: https://git.baikalelectronics.ru/sdk/?a=commitdiff_plain;h=f7ee54f050dcdc56622a9c9746f65d7e0af15938;p=kernel.git

MIPS: vdso: Utilize __pa() for gic_pfn

[ Upstream commit a911ad58a1d56086a06cc4a178e35ccd3a49d4cb ]

The GIC user offset is mapped into every process' virtual address and is
therefore part of the hot-path of arch_setup_additional_pages(). Utilize
__pa() such that we are more optimal even when CONFIG_DEBUG_VIRTUAL is
enabled, and while at it utilize PFN_DOWN() instead of open-coding the
right shift by PAGE_SHIFT.

Reported-by: Greg Ungerer <gerg@kernel.org>
Suggested-by: Serge Semin <fancer.lancer@gmail.com>
Fixes: f6c79b8d8bc7 ("MIPS: Add support for CONFIG_DEBUG_VIRTUAL")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Greg Ungerer <gerg@kernel.org>
Tested-by: Greg Ungerer <gerg@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/arch/mips/kernel/vdso.c b/arch/mips/kernel/vdso.c
index 3d0cf471f2fe1..b2cc2c2dd4bfc 100644
--- a/arch/mips/kernel/vdso.c
+++ b/arch/mips/kernel/vdso.c
@@ -159,7 +159,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 	/* Map GIC user page. */
 	if (gic_size) {
 		gic_base = (unsigned long)mips_gic_base + MIPS_GIC_USER_OFS;
-		gic_pfn = virt_to_phys((void *)gic_base) >> PAGE_SHIFT;
+		gic_pfn = PFN_DOWN(__pa(gic_base));
 
 		ret = io_remap_pfn_range(vma, base, gic_pfn, gic_size,
 					 pgprot_noncached(vma->vm_page_prot));