[patch 12/13] Remove uv bios and efi code related to (now unused) EFI_UV1_MEMMAP

From: steve.wahl@hpe.com
To: Jonathan Corbet <corbet@lwn.net>,
	Ard Biesheuvel <ardb@kernel.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
	x86@kernel.org, "H. Peter Anvin" <hpa@zytor.com>,
	Darren Hart <dvhart@infradead.org>,
	Andy Shevchenko <andy@infradead.org>,
	Mauro Carvalho Chehab <mchehab+huawei@kernel.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	"Paul E. McKenney" <paulmck@kernel.org>,
	Pawan Gupta <pawan.kumar.gupta@linux.intel.com>,
	Juergen Gross <jgross@suse.com>,
	Mike Kravetz <mike.kravetz@oracle.com>,
	Oliver Neukum <oneukum@suse.com>,
	Mike Travis <mike.travis@hpe.com>,
	Steve Wahl <steve.wahl@hpe.com>,
	Dimitri Sivanich <dimitri.sivanich@hpe.com>,
	Benjamin Thiel <b.thiel@posteo.de>,
	Andy Lutomirski <luto@kernel.org>, Arnd Bergmann <arnd@arndb.de>,
	James Morris <jmorris@namei.org>,
	David Howells <dhowells@redhat.com>,
	Kees Cook <keescook@chromium.org>, Dave Young <dyoung@redhat.com>,
	Dan Williams <dan.j.williams@intel.com>,
	Logan Gunthorpe <logang@deltatee.com>,
	Alexandre Chartre <alexandre.chartre@oracle.com>,
	"Peter Zijlstra (Intel)" <peterz@infradead.org>,
	Austin Kim <austindh.kim@gmail.com>,
	Alexey Dobriyan <adobriyan@gmail.com>,
	linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-efi@vger.kernel.org
Cc: Russ Anderson <rja@hpe.com>
Subject: [patch 12/13] Remove uv bios and efi code related to (now unused) EFI_UV1_MEMMAP
Date: Wed, 01 Jul 2020 09:17:43 -0500	[thread overview]
Message-ID: <20200701141732.957084206@hpe.com> (raw)
In-Reply-To: 20200701141731.377252388@hpe.com

With UV1 removed, EFI_UV1_MEMMAP is not used.  Remove code used by it
in arch/x86/platform/uv/bios_uv.c and turn off code in
arch/x86/platform/efi/efi.c that referenced this code.

Signed-off-by: Steve Wahl <steve.wahl@hpe.com>
---
 arch/x86/platform/efi/efi.c    |    2 
 arch/x86/platform/uv/bios_uv.c |  159 -----------------------------------------
 2 files changed, 2 insertions(+), 159 deletions(-)

--- linux.orig/arch/x86/platform/uv/bios_uv.c	2020-06-25 16:13:51.765087047 -0500
+++ linux/arch/x86/platform/uv/bios_uv.c	2020-06-25 16:14:29.821045358 -0500
@@ -30,17 +30,7 @@ static s64 __uv_bios_call(enum uv_bios_c
 		 */
 		return BIOS_STATUS_UNIMPLEMENTED;
 
-	/*
-	 * If EFI_UV1_MEMMAP is set, we need to fall back to using our old EFI
-	 * callback method, which uses efi_call() directly, with the kernel page tables:
-	 */
-	if (unlikely(efi_enabled(EFI_UV1_MEMMAP))) {
-		kernel_fpu_begin();
-		ret = efi_call((void *)__va(tab->function), (u64)which, a1, a2, a3, a4, a5);
-		kernel_fpu_end();
-	} else {
-		ret = efi_call_virt_pointer(tab, function, (u64)which, a1, a2, a3, a4, a5);
-	}
+	ret = efi_call_virt_pointer(tab, function, (u64)which, a1, a2, a3, a4, a5);
 
 	return ret;
 }
@@ -209,150 +199,3 @@ int uv_bios_init(void)
 	pr_info("UV: UVsystab: Revision:%x\n", uv_systab->revision);
 	return 0;
 }
-
-static void __init early_code_mapping_set_exec(int executable)
-{
-	efi_memory_desc_t *md;
-
-	if (!(__supported_pte_mask & _PAGE_NX))
-		return;
-
-	/* Make EFI service code area executable */
-	for_each_efi_memory_desc(md) {
-		if (md->type == EFI_RUNTIME_SERVICES_CODE ||
-		    md->type == EFI_BOOT_SERVICES_CODE)
-			efi_set_executable(md, executable);
-	}
-}
-
-void __init efi_uv1_memmap_phys_epilog(pgd_t *save_pgd)
-{
-	/*
-	 * After the lock is released, the original page table is restored.
-	 */
-	int pgd_idx, i;
-	int nr_pgds;
-	pgd_t *pgd;
-	p4d_t *p4d;
-	pud_t *pud;
-
-	nr_pgds = DIV_ROUND_UP((max_pfn << PAGE_SHIFT) , PGDIR_SIZE);
-
-	for (pgd_idx = 0; pgd_idx < nr_pgds; pgd_idx++) {
-		pgd = pgd_offset_k(pgd_idx * PGDIR_SIZE);
-		set_pgd(pgd_offset_k(pgd_idx * PGDIR_SIZE), save_pgd[pgd_idx]);
-
-		if (!pgd_present(*pgd))
-			continue;
-
-		for (i = 0; i < PTRS_PER_P4D; i++) {
-			p4d = p4d_offset(pgd,
-					 pgd_idx * PGDIR_SIZE + i * P4D_SIZE);
-
-			if (!p4d_present(*p4d))
-				continue;
-
-			pud = (pud_t *)p4d_page_vaddr(*p4d);
-			pud_free(&init_mm, pud);
-		}
-
-		p4d = (p4d_t *)pgd_page_vaddr(*pgd);
-		p4d_free(&init_mm, p4d);
-	}
-
-	kfree(save_pgd);
-
-	__flush_tlb_all();
-	early_code_mapping_set_exec(0);
-}
-
-pgd_t * __init efi_uv1_memmap_phys_prolog(void)
-{
-	unsigned long vaddr, addr_pgd, addr_p4d, addr_pud;
-	pgd_t *save_pgd, *pgd_k, *pgd_efi;
-	p4d_t *p4d, *p4d_k, *p4d_efi;
-	pud_t *pud;
-
-	int pgd;
-	int n_pgds, i, j;
-
-	early_code_mapping_set_exec(1);
-
-	n_pgds = DIV_ROUND_UP((max_pfn << PAGE_SHIFT), PGDIR_SIZE);
-	save_pgd = kmalloc_array(n_pgds, sizeof(*save_pgd), GFP_KERNEL);
-	if (!save_pgd)
-		return NULL;
-
-	/*
-	 * Build 1:1 identity mapping for UV1 memmap usage. Note that
-	 * PAGE_OFFSET is PGDIR_SIZE aligned when KASLR is disabled, while
-	 * it is PUD_SIZE ALIGNED with KASLR enabled. So for a given physical
-	 * address X, the pud_index(X) != pud_index(__va(X)), we can only copy
-	 * PUD entry of __va(X) to fill in pud entry of X to build 1:1 mapping.
-	 * This means here we can only reuse the PMD tables of the direct mapping.
-	 */
-	for (pgd = 0; pgd < n_pgds; pgd++) {
-		addr_pgd = (unsigned long)(pgd * PGDIR_SIZE);
-		vaddr = (unsigned long)__va(pgd * PGDIR_SIZE);
-		pgd_efi = pgd_offset_k(addr_pgd);
-		save_pgd[pgd] = *pgd_efi;
-
-		p4d = p4d_alloc(&init_mm, pgd_efi, addr_pgd);
-		if (!p4d) {
-			pr_err("Failed to allocate p4d table!\n");
-			goto out;
-		}
-
-		for (i = 0; i < PTRS_PER_P4D; i++) {
-			addr_p4d = addr_pgd + i * P4D_SIZE;
-			p4d_efi = p4d + p4d_index(addr_p4d);
-
-			pud = pud_alloc(&init_mm, p4d_efi, addr_p4d);
-			if (!pud) {
-				pr_err("Failed to allocate pud table!\n");
-				goto out;
-			}
-
-			for (j = 0; j < PTRS_PER_PUD; j++) {
-				addr_pud = addr_p4d + j * PUD_SIZE;
-
-				if (addr_pud > (max_pfn << PAGE_SHIFT))
-					break;
-
-				vaddr = (unsigned long)__va(addr_pud);
-
-				pgd_k = pgd_offset_k(vaddr);
-				p4d_k = p4d_offset(pgd_k, vaddr);
-				pud[j] = *pud_offset(p4d_k, vaddr);
-			}
-		}
-		pgd_offset_k(pgd * PGDIR_SIZE)->pgd &= ~_PAGE_NX;
-	}
-
-	__flush_tlb_all();
-	return save_pgd;
-out:
-	efi_uv1_memmap_phys_epilog(save_pgd);
-	return NULL;
-}
-
-void __iomem *__init efi_ioremap(unsigned long phys_addr, unsigned long size,
-				 u32 type, u64 attribute)
-{
-	unsigned long last_map_pfn;
-
-	if (type == EFI_MEMORY_MAPPED_IO)
-		return ioremap(phys_addr, size);
-
-	last_map_pfn = init_memory_mapping(phys_addr, phys_addr + size,
-					   PAGE_KERNEL);
-	if ((last_map_pfn << PAGE_SHIFT) < phys_addr + size) {
-		unsigned long top = last_map_pfn << PAGE_SHIFT;
-		efi_ioremap(top, size - (top - phys_addr), type, attribute);
-	}
-
-	if (!(attribute & EFI_MEMORY_WB))
-		efi_memory_uc((u64)(unsigned long)__va(phys_addr), size);
-
-	return (void __iomem *)__va(phys_addr);
-}
--- linux.orig/arch/x86/platform/efi/efi.c	2020-06-25 16:13:54.637083901 -0500
+++ linux/arch/x86/platform/efi/efi.c	2020-06-25 16:15:14.532996386 -0500
@@ -496,7 +496,7 @@ void __init efi_init(void)
 		efi_print_memmap();
 }
 
-#if defined(CONFIG_X86_32) || defined(CONFIG_X86_UV)
+#if defined(CONFIG_X86_32)
 
 void __init efi_set_executable(efi_memory_desc_t *md, bool executable)
 {

