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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /arch/x86/mm/ioremap.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/x86/mm/ioremap.c')
-rw-r--r--arch/x86/mm/ioremap.c931
1 files changed, 931 insertions, 0 deletions
diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
new file mode 100644
index 000000000..6453fbaed
--- /dev/null
+++ b/arch/x86/mm/ioremap.c
@@ -0,0 +1,931 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Re-map IO memory to kernel address space so that we can access it.
+ * This is needed for high PCI addresses that aren't mapped in the
+ * 640k-1MB IO memory area on PC's
+ *
+ * (C) Copyright 1995 1996 Linus Torvalds
+ */
+
+#include <linux/memblock.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/mmiotrace.h>
+#include <linux/cc_platform.h>
+#include <linux/efi.h>
+#include <linux/pgtable.h>
+#include <linux/kmsan.h>
+
+#include <asm/set_memory.h>
+#include <asm/e820/api.h>
+#include <asm/efi.h>
+#include <asm/fixmap.h>
+#include <asm/tlbflush.h>
+#include <asm/pgalloc.h>
+#include <asm/memtype.h>
+#include <asm/setup.h>
+
+#include "physaddr.h"
+
+/*
+ * Descriptor controlling ioremap() behavior.
+ */
+struct ioremap_desc {
+ unsigned int flags;
+};
+
+/*
+ * Fix up the linear direct mapping of the kernel to avoid cache attribute
+ * conflicts.
+ */
+int ioremap_change_attr(unsigned long vaddr, unsigned long size,
+ enum page_cache_mode pcm)
+{
+ unsigned long nrpages = size >> PAGE_SHIFT;
+ int err;
+
+ switch (pcm) {
+ case _PAGE_CACHE_MODE_UC:
+ default:
+ err = _set_memory_uc(vaddr, nrpages);
+ break;
+ case _PAGE_CACHE_MODE_WC:
+ err = _set_memory_wc(vaddr, nrpages);
+ break;
+ case _PAGE_CACHE_MODE_WT:
+ err = _set_memory_wt(vaddr, nrpages);
+ break;
+ case _PAGE_CACHE_MODE_WB:
+ err = _set_memory_wb(vaddr, nrpages);
+ break;
+ }
+
+ return err;
+}
+
+/* Does the range (or a subset of) contain normal RAM? */
+static unsigned int __ioremap_check_ram(struct resource *res)
+{
+ unsigned long start_pfn, stop_pfn;
+ unsigned long i;
+
+ if ((res->flags & IORESOURCE_SYSTEM_RAM) != IORESOURCE_SYSTEM_RAM)
+ return 0;
+
+ start_pfn = (res->start + PAGE_SIZE - 1) >> PAGE_SHIFT;
+ stop_pfn = (res->end + 1) >> PAGE_SHIFT;
+ if (stop_pfn > start_pfn) {
+ for (i = 0; i < (stop_pfn - start_pfn); ++i)
+ if (pfn_valid(start_pfn + i) &&
+ !PageReserved(pfn_to_page(start_pfn + i)))
+ return IORES_MAP_SYSTEM_RAM;
+ }
+
+ return 0;
+}
+
+/*
+ * In a SEV guest, NONE and RESERVED should not be mapped encrypted because
+ * there the whole memory is already encrypted.
+ */
+static unsigned int __ioremap_check_encrypted(struct resource *res)
+{
+ if (!cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT))
+ return 0;
+
+ switch (res->desc) {
+ case IORES_DESC_NONE:
+ case IORES_DESC_RESERVED:
+ break;
+ default:
+ return IORES_MAP_ENCRYPTED;
+ }
+
+ return 0;
+}
+
+/*
+ * The EFI runtime services data area is not covered by walk_mem_res(), but must
+ * be mapped encrypted when SEV is active.
+ */
+static void __ioremap_check_other(resource_size_t addr, struct ioremap_desc *desc)
+{
+ if (!cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT))
+ return;
+
+ if (!IS_ENABLED(CONFIG_EFI))
+ return;
+
+ if (efi_mem_type(addr) == EFI_RUNTIME_SERVICES_DATA ||
+ (efi_mem_type(addr) == EFI_BOOT_SERVICES_DATA &&
+ efi_mem_attributes(addr) & EFI_MEMORY_RUNTIME))
+ desc->flags |= IORES_MAP_ENCRYPTED;
+}
+
+static int __ioremap_collect_map_flags(struct resource *res, void *arg)
+{
+ struct ioremap_desc *desc = arg;
+
+ if (!(desc->flags & IORES_MAP_SYSTEM_RAM))
+ desc->flags |= __ioremap_check_ram(res);
+
+ if (!(desc->flags & IORES_MAP_ENCRYPTED))
+ desc->flags |= __ioremap_check_encrypted(res);
+
+ return ((desc->flags & (IORES_MAP_SYSTEM_RAM | IORES_MAP_ENCRYPTED)) ==
+ (IORES_MAP_SYSTEM_RAM | IORES_MAP_ENCRYPTED));
+}
+
+/*
+ * To avoid multiple resource walks, this function walks resources marked as
+ * IORESOURCE_MEM and IORESOURCE_BUSY and looking for system RAM and/or a
+ * resource described not as IORES_DESC_NONE (e.g. IORES_DESC_ACPI_TABLES).
+ *
+ * After that, deal with misc other ranges in __ioremap_check_other() which do
+ * not fall into the above category.
+ */
+static void __ioremap_check_mem(resource_size_t addr, unsigned long size,
+ struct ioremap_desc *desc)
+{
+ u64 start, end;
+
+ start = (u64)addr;
+ end = start + size - 1;
+ memset(desc, 0, sizeof(struct ioremap_desc));
+
+ walk_mem_res(start, end, desc, __ioremap_collect_map_flags);
+
+ __ioremap_check_other(addr, desc);
+}
+
+/*
+ * Remap an arbitrary physical address space into the kernel virtual
+ * address space. It transparently creates kernel huge I/O mapping when
+ * the physical address is aligned by a huge page size (1GB or 2MB) and
+ * the requested size is at least the huge page size.
+ *
+ * NOTE: MTRRs can override PAT memory types with a 4KB granularity.
+ * Therefore, the mapping code falls back to use a smaller page toward 4KB
+ * when a mapping range is covered by non-WB type of MTRRs.
+ *
+ * NOTE! We need to allow non-page-aligned mappings too: we will obviously
+ * have to convert them into an offset in a page-aligned mapping, but the
+ * caller shouldn't need to know that small detail.
+ */
+static void __iomem *
+__ioremap_caller(resource_size_t phys_addr, unsigned long size,
+ enum page_cache_mode pcm, void *caller, bool encrypted)
+{
+ unsigned long offset, vaddr;
+ resource_size_t last_addr;
+ const resource_size_t unaligned_phys_addr = phys_addr;
+ const unsigned long unaligned_size = size;
+ struct ioremap_desc io_desc;
+ struct vm_struct *area;
+ enum page_cache_mode new_pcm;
+ pgprot_t prot;
+ int retval;
+ void __iomem *ret_addr;
+
+ /* Don't allow wraparound or zero size */
+ last_addr = phys_addr + size - 1;
+ if (!size || last_addr < phys_addr)
+ return NULL;
+
+ if (!phys_addr_valid(phys_addr)) {
+ printk(KERN_WARNING "ioremap: invalid physical address %llx\n",
+ (unsigned long long)phys_addr);
+ WARN_ON_ONCE(1);
+ return NULL;
+ }
+
+ __ioremap_check_mem(phys_addr, size, &io_desc);
+
+ /*
+ * Don't allow anybody to remap normal RAM that we're using..
+ */
+ if (io_desc.flags & IORES_MAP_SYSTEM_RAM) {
+ WARN_ONCE(1, "ioremap on RAM at %pa - %pa\n",
+ &phys_addr, &last_addr);
+ return NULL;
+ }
+
+ /*
+ * Mappings have to be page-aligned
+ */
+ offset = phys_addr & ~PAGE_MASK;
+ phys_addr &= PAGE_MASK;
+ size = PAGE_ALIGN(last_addr+1) - phys_addr;
+
+ /*
+ * Mask out any bits not part of the actual physical
+ * address, like memory encryption bits.
+ */
+ phys_addr &= PHYSICAL_PAGE_MASK;
+
+ retval = memtype_reserve(phys_addr, (u64)phys_addr + size,
+ pcm, &new_pcm);
+ if (retval) {
+ printk(KERN_ERR "ioremap memtype_reserve failed %d\n", retval);
+ return NULL;
+ }
+
+ if (pcm != new_pcm) {
+ if (!is_new_memtype_allowed(phys_addr, size, pcm, new_pcm)) {
+ printk(KERN_ERR
+ "ioremap error for 0x%llx-0x%llx, requested 0x%x, got 0x%x\n",
+ (unsigned long long)phys_addr,
+ (unsigned long long)(phys_addr + size),
+ pcm, new_pcm);
+ goto err_free_memtype;
+ }
+ pcm = new_pcm;
+ }
+
+ /*
+ * If the page being mapped is in memory and SEV is active then
+ * make sure the memory encryption attribute is enabled in the
+ * resulting mapping.
+ * In TDX guests, memory is marked private by default. If encryption
+ * is not requested (using encrypted), explicitly set decrypt
+ * attribute in all IOREMAPPED memory.
+ */
+ prot = PAGE_KERNEL_IO;
+ if ((io_desc.flags & IORES_MAP_ENCRYPTED) || encrypted)
+ prot = pgprot_encrypted(prot);
+ else
+ prot = pgprot_decrypted(prot);
+
+ switch (pcm) {
+ case _PAGE_CACHE_MODE_UC:
+ default:
+ prot = __pgprot(pgprot_val(prot) |
+ cachemode2protval(_PAGE_CACHE_MODE_UC));
+ break;
+ case _PAGE_CACHE_MODE_UC_MINUS:
+ prot = __pgprot(pgprot_val(prot) |
+ cachemode2protval(_PAGE_CACHE_MODE_UC_MINUS));
+ break;
+ case _PAGE_CACHE_MODE_WC:
+ prot = __pgprot(pgprot_val(prot) |
+ cachemode2protval(_PAGE_CACHE_MODE_WC));
+ break;
+ case _PAGE_CACHE_MODE_WT:
+ prot = __pgprot(pgprot_val(prot) |
+ cachemode2protval(_PAGE_CACHE_MODE_WT));
+ break;
+ case _PAGE_CACHE_MODE_WB:
+ break;
+ }
+
+ /*
+ * Ok, go for it..
+ */
+ area = get_vm_area_caller(size, VM_IOREMAP, caller);
+ if (!area)
+ goto err_free_memtype;
+ area->phys_addr = phys_addr;
+ vaddr = (unsigned long) area->addr;
+
+ if (memtype_kernel_map_sync(phys_addr, size, pcm))
+ goto err_free_area;
+
+ if (ioremap_page_range(vaddr, vaddr + size, phys_addr, prot))
+ goto err_free_area;
+
+ ret_addr = (void __iomem *) (vaddr + offset);
+ mmiotrace_ioremap(unaligned_phys_addr, unaligned_size, ret_addr);
+
+ /*
+ * Check if the request spans more than any BAR in the iomem resource
+ * tree.
+ */
+ if (iomem_map_sanity_check(unaligned_phys_addr, unaligned_size))
+ pr_warn("caller %pS mapping multiple BARs\n", caller);
+
+ return ret_addr;
+err_free_area:
+ free_vm_area(area);
+err_free_memtype:
+ memtype_free(phys_addr, phys_addr + size);
+ return NULL;
+}
+
+/**
+ * ioremap - map bus memory into CPU space
+ * @phys_addr: bus address of the memory
+ * @size: size of the resource to map
+ *
+ * ioremap performs a platform specific sequence of operations to
+ * make bus memory CPU accessible via the readb/readw/readl/writeb/
+ * writew/writel functions and the other mmio helpers. The returned
+ * address is not guaranteed to be usable directly as a virtual
+ * address.
+ *
+ * This version of ioremap ensures that the memory is marked uncachable
+ * on the CPU as well as honouring existing caching rules from things like
+ * the PCI bus. Note that there are other caches and buffers on many
+ * busses. In particular driver authors should read up on PCI writes
+ *
+ * It's useful if some control registers are in such an area and
+ * write combining or read caching is not desirable:
+ *
+ * Must be freed with iounmap.
+ */
+void __iomem *ioremap(resource_size_t phys_addr, unsigned long size)
+{
+ /*
+ * Ideally, this should be:
+ * pat_enabled() ? _PAGE_CACHE_MODE_UC : _PAGE_CACHE_MODE_UC_MINUS;
+ *
+ * Till we fix all X drivers to use ioremap_wc(), we will use
+ * UC MINUS. Drivers that are certain they need or can already
+ * be converted over to strong UC can use ioremap_uc().
+ */
+ enum page_cache_mode pcm = _PAGE_CACHE_MODE_UC_MINUS;
+
+ return __ioremap_caller(phys_addr, size, pcm,
+ __builtin_return_address(0), false);
+}
+EXPORT_SYMBOL(ioremap);
+
+/**
+ * ioremap_uc - map bus memory into CPU space as strongly uncachable
+ * @phys_addr: bus address of the memory
+ * @size: size of the resource to map
+ *
+ * ioremap_uc performs a platform specific sequence of operations to
+ * make bus memory CPU accessible via the readb/readw/readl/writeb/
+ * writew/writel functions and the other mmio helpers. The returned
+ * address is not guaranteed to be usable directly as a virtual
+ * address.
+ *
+ * This version of ioremap ensures that the memory is marked with a strong
+ * preference as completely uncachable on the CPU when possible. For non-PAT
+ * systems this ends up setting page-attribute flags PCD=1, PWT=1. For PAT
+ * systems this will set the PAT entry for the pages as strong UC. This call
+ * will honor existing caching rules from things like the PCI bus. Note that
+ * there are other caches and buffers on many busses. In particular driver
+ * authors should read up on PCI writes.
+ *
+ * It's useful if some control registers are in such an area and
+ * write combining or read caching is not desirable:
+ *
+ * Must be freed with iounmap.
+ */
+void __iomem *ioremap_uc(resource_size_t phys_addr, unsigned long size)
+{
+ enum page_cache_mode pcm = _PAGE_CACHE_MODE_UC;
+
+ return __ioremap_caller(phys_addr, size, pcm,
+ __builtin_return_address(0), false);
+}
+EXPORT_SYMBOL_GPL(ioremap_uc);
+
+/**
+ * ioremap_wc - map memory into CPU space write combined
+ * @phys_addr: bus address of the memory
+ * @size: size of the resource to map
+ *
+ * This version of ioremap ensures that the memory is marked write combining.
+ * Write combining allows faster writes to some hardware devices.
+ *
+ * Must be freed with iounmap.
+ */
+void __iomem *ioremap_wc(resource_size_t phys_addr, unsigned long size)
+{
+ return __ioremap_caller(phys_addr, size, _PAGE_CACHE_MODE_WC,
+ __builtin_return_address(0), false);
+}
+EXPORT_SYMBOL(ioremap_wc);
+
+/**
+ * ioremap_wt - map memory into CPU space write through
+ * @phys_addr: bus address of the memory
+ * @size: size of the resource to map
+ *
+ * This version of ioremap ensures that the memory is marked write through.
+ * Write through stores data into memory while keeping the cache up-to-date.
+ *
+ * Must be freed with iounmap.
+ */
+void __iomem *ioremap_wt(resource_size_t phys_addr, unsigned long size)
+{
+ return __ioremap_caller(phys_addr, size, _PAGE_CACHE_MODE_WT,
+ __builtin_return_address(0), false);
+}
+EXPORT_SYMBOL(ioremap_wt);
+
+void __iomem *ioremap_encrypted(resource_size_t phys_addr, unsigned long size)
+{
+ return __ioremap_caller(phys_addr, size, _PAGE_CACHE_MODE_WB,
+ __builtin_return_address(0), true);
+}
+EXPORT_SYMBOL(ioremap_encrypted);
+
+void __iomem *ioremap_cache(resource_size_t phys_addr, unsigned long size)
+{
+ return __ioremap_caller(phys_addr, size, _PAGE_CACHE_MODE_WB,
+ __builtin_return_address(0), false);
+}
+EXPORT_SYMBOL(ioremap_cache);
+
+void __iomem *ioremap_prot(resource_size_t phys_addr, unsigned long size,
+ unsigned long prot_val)
+{
+ return __ioremap_caller(phys_addr, size,
+ pgprot2cachemode(__pgprot(prot_val)),
+ __builtin_return_address(0), false);
+}
+EXPORT_SYMBOL(ioremap_prot);
+
+/**
+ * iounmap - Free a IO remapping
+ * @addr: virtual address from ioremap_*
+ *
+ * Caller must ensure there is only one unmapping for the same pointer.
+ */
+void iounmap(volatile void __iomem *addr)
+{
+ struct vm_struct *p, *o;
+
+ if ((void __force *)addr <= high_memory)
+ return;
+
+ /*
+ * The PCI/ISA range special-casing was removed from __ioremap()
+ * so this check, in theory, can be removed. However, there are
+ * cases where iounmap() is called for addresses not obtained via
+ * ioremap() (vga16fb for example). Add a warning so that these
+ * cases can be caught and fixed.
+ */
+ if ((void __force *)addr >= phys_to_virt(ISA_START_ADDRESS) &&
+ (void __force *)addr < phys_to_virt(ISA_END_ADDRESS)) {
+ WARN(1, "iounmap() called for ISA range not obtained using ioremap()\n");
+ return;
+ }
+
+ mmiotrace_iounmap(addr);
+
+ addr = (volatile void __iomem *)
+ (PAGE_MASK & (unsigned long __force)addr);
+
+ /* Use the vm area unlocked, assuming the caller
+ ensures there isn't another iounmap for the same address
+ in parallel. Reuse of the virtual address is prevented by
+ leaving it in the global lists until we're done with it.
+ cpa takes care of the direct mappings. */
+ p = find_vm_area((void __force *)addr);
+
+ if (!p) {
+ printk(KERN_ERR "iounmap: bad address %p\n", addr);
+ dump_stack();
+ return;
+ }
+
+ kmsan_iounmap_page_range((unsigned long)addr,
+ (unsigned long)addr + get_vm_area_size(p));
+ memtype_free(p->phys_addr, p->phys_addr + get_vm_area_size(p));
+
+ /* Finally remove it */
+ o = remove_vm_area((void __force *)addr);
+ BUG_ON(p != o || o == NULL);
+ kfree(p);
+}
+EXPORT_SYMBOL(iounmap);
+
+/*
+ * Convert a physical pointer to a virtual kernel pointer for /dev/mem
+ * access
+ */
+void *xlate_dev_mem_ptr(phys_addr_t phys)
+{
+ unsigned long start = phys & PAGE_MASK;
+ unsigned long offset = phys & ~PAGE_MASK;
+ void *vaddr;
+
+ /* memremap() maps if RAM, otherwise falls back to ioremap() */
+ vaddr = memremap(start, PAGE_SIZE, MEMREMAP_WB);
+
+ /* Only add the offset on success and return NULL if memremap() failed */
+ if (vaddr)
+ vaddr += offset;
+
+ return vaddr;
+}
+
+void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr)
+{
+ memunmap((void *)((unsigned long)addr & PAGE_MASK));
+}
+
+#ifdef CONFIG_AMD_MEM_ENCRYPT
+/*
+ * Examine the physical address to determine if it is an area of memory
+ * that should be mapped decrypted. If the memory is not part of the
+ * kernel usable area it was accessed and created decrypted, so these
+ * areas should be mapped decrypted. And since the encryption key can
+ * change across reboots, persistent memory should also be mapped
+ * decrypted.
+ *
+ * If SEV is active, that implies that BIOS/UEFI also ran encrypted so
+ * only persistent memory should be mapped decrypted.
+ */
+static bool memremap_should_map_decrypted(resource_size_t phys_addr,
+ unsigned long size)
+{
+ int is_pmem;
+
+ /*
+ * Check if the address is part of a persistent memory region.
+ * This check covers areas added by E820, EFI and ACPI.
+ */
+ is_pmem = region_intersects(phys_addr, size, IORESOURCE_MEM,
+ IORES_DESC_PERSISTENT_MEMORY);
+ if (is_pmem != REGION_DISJOINT)
+ return true;
+
+ /*
+ * Check if the non-volatile attribute is set for an EFI
+ * reserved area.
+ */
+ if (efi_enabled(EFI_BOOT)) {
+ switch (efi_mem_type(phys_addr)) {
+ case EFI_RESERVED_TYPE:
+ if (efi_mem_attributes(phys_addr) & EFI_MEMORY_NV)
+ return true;
+ break;
+ default:
+ break;
+ }
+ }
+
+ /* Check if the address is outside kernel usable area */
+ switch (e820__get_entry_type(phys_addr, phys_addr + size - 1)) {
+ case E820_TYPE_RESERVED:
+ case E820_TYPE_ACPI:
+ case E820_TYPE_NVS:
+ case E820_TYPE_UNUSABLE:
+ /* For SEV, these areas are encrypted */
+ if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT))
+ break;
+ fallthrough;
+
+ case E820_TYPE_PRAM:
+ return true;
+ default:
+ break;
+ }
+
+ return false;
+}
+
+/*
+ * Examine the physical address to determine if it is EFI data. Check
+ * it against the boot params structure and EFI tables and memory types.
+ */
+static bool memremap_is_efi_data(resource_size_t phys_addr,
+ unsigned long size)
+{
+ u64 paddr;
+
+ /* Check if the address is part of EFI boot/runtime data */
+ if (!efi_enabled(EFI_BOOT))
+ return false;
+
+ paddr = boot_params.efi_info.efi_memmap_hi;
+ paddr <<= 32;
+ paddr |= boot_params.efi_info.efi_memmap;
+ if (phys_addr == paddr)
+ return true;
+
+ paddr = boot_params.efi_info.efi_systab_hi;
+ paddr <<= 32;
+ paddr |= boot_params.efi_info.efi_systab;
+ if (phys_addr == paddr)
+ return true;
+
+ if (efi_is_table_address(phys_addr))
+ return true;
+
+ switch (efi_mem_type(phys_addr)) {
+ case EFI_BOOT_SERVICES_DATA:
+ case EFI_RUNTIME_SERVICES_DATA:
+ return true;
+ default:
+ break;
+ }
+
+ return false;
+}
+
+/*
+ * Examine the physical address to determine if it is boot data by checking
+ * it against the boot params setup_data chain.
+ */
+static bool memremap_is_setup_data(resource_size_t phys_addr,
+ unsigned long size)
+{
+ struct setup_indirect *indirect;
+ struct setup_data *data;
+ u64 paddr, paddr_next;
+
+ paddr = boot_params.hdr.setup_data;
+ while (paddr) {
+ unsigned int len;
+
+ if (phys_addr == paddr)
+ return true;
+
+ data = memremap(paddr, sizeof(*data),
+ MEMREMAP_WB | MEMREMAP_DEC);
+ if (!data) {
+ pr_warn("failed to memremap setup_data entry\n");
+ return false;
+ }
+
+ paddr_next = data->next;
+ len = data->len;
+
+ if ((phys_addr > paddr) && (phys_addr < (paddr + len))) {
+ memunmap(data);
+ return true;
+ }
+
+ if (data->type == SETUP_INDIRECT) {
+ memunmap(data);
+ data = memremap(paddr, sizeof(*data) + len,
+ MEMREMAP_WB | MEMREMAP_DEC);
+ if (!data) {
+ pr_warn("failed to memremap indirect setup_data\n");
+ return false;
+ }
+
+ indirect = (struct setup_indirect *)data->data;
+
+ if (indirect->type != SETUP_INDIRECT) {
+ paddr = indirect->addr;
+ len = indirect->len;
+ }
+ }
+
+ memunmap(data);
+
+ if ((phys_addr > paddr) && (phys_addr < (paddr + len)))
+ return true;
+
+ paddr = paddr_next;
+ }
+
+ return false;
+}
+
+/*
+ * Examine the physical address to determine if it is boot data by checking
+ * it against the boot params setup_data chain (early boot version).
+ */
+static bool __init early_memremap_is_setup_data(resource_size_t phys_addr,
+ unsigned long size)
+{
+ struct setup_indirect *indirect;
+ struct setup_data *data;
+ u64 paddr, paddr_next;
+
+ paddr = boot_params.hdr.setup_data;
+ while (paddr) {
+ unsigned int len, size;
+
+ if (phys_addr == paddr)
+ return true;
+
+ data = early_memremap_decrypted(paddr, sizeof(*data));
+ if (!data) {
+ pr_warn("failed to early memremap setup_data entry\n");
+ return false;
+ }
+
+ size = sizeof(*data);
+
+ paddr_next = data->next;
+ len = data->len;
+
+ if ((phys_addr > paddr) && (phys_addr < (paddr + len))) {
+ early_memunmap(data, sizeof(*data));
+ return true;
+ }
+
+ if (data->type == SETUP_INDIRECT) {
+ size += len;
+ early_memunmap(data, sizeof(*data));
+ data = early_memremap_decrypted(paddr, size);
+ if (!data) {
+ pr_warn("failed to early memremap indirect setup_data\n");
+ return false;
+ }
+
+ indirect = (struct setup_indirect *)data->data;
+
+ if (indirect->type != SETUP_INDIRECT) {
+ paddr = indirect->addr;
+ len = indirect->len;
+ }
+ }
+
+ early_memunmap(data, size);
+
+ if ((phys_addr > paddr) && (phys_addr < (paddr + len)))
+ return true;
+
+ paddr = paddr_next;
+ }
+
+ return false;
+}
+
+/*
+ * Architecture function to determine if RAM remap is allowed. By default, a
+ * RAM remap will map the data as encrypted. Determine if a RAM remap should
+ * not be done so that the data will be mapped decrypted.
+ */
+bool arch_memremap_can_ram_remap(resource_size_t phys_addr, unsigned long size,
+ unsigned long flags)
+{
+ if (!cc_platform_has(CC_ATTR_MEM_ENCRYPT))
+ return true;
+
+ if (flags & MEMREMAP_ENC)
+ return true;
+
+ if (flags & MEMREMAP_DEC)
+ return false;
+
+ if (cc_platform_has(CC_ATTR_HOST_MEM_ENCRYPT)) {
+ if (memremap_is_setup_data(phys_addr, size) ||
+ memremap_is_efi_data(phys_addr, size))
+ return false;
+ }
+
+ return !memremap_should_map_decrypted(phys_addr, size);
+}
+
+/*
+ * Architecture override of __weak function to adjust the protection attributes
+ * used when remapping memory. By default, early_memremap() will map the data
+ * as encrypted. Determine if an encrypted mapping should not be done and set
+ * the appropriate protection attributes.
+ */
+pgprot_t __init early_memremap_pgprot_adjust(resource_size_t phys_addr,
+ unsigned long size,
+ pgprot_t prot)
+{
+ bool encrypted_prot;
+
+ if (!cc_platform_has(CC_ATTR_MEM_ENCRYPT))
+ return prot;
+
+ encrypted_prot = true;
+
+ if (cc_platform_has(CC_ATTR_HOST_MEM_ENCRYPT)) {
+ if (early_memremap_is_setup_data(phys_addr, size) ||
+ memremap_is_efi_data(phys_addr, size))
+ encrypted_prot = false;
+ }
+
+ if (encrypted_prot && memremap_should_map_decrypted(phys_addr, size))
+ encrypted_prot = false;
+
+ return encrypted_prot ? pgprot_encrypted(prot)
+ : pgprot_decrypted(prot);
+}
+
+bool phys_mem_access_encrypted(unsigned long phys_addr, unsigned long size)
+{
+ return arch_memremap_can_ram_remap(phys_addr, size, 0);
+}
+
+/* Remap memory with encryption */
+void __init *early_memremap_encrypted(resource_size_t phys_addr,
+ unsigned long size)
+{
+ return early_memremap_prot(phys_addr, size, __PAGE_KERNEL_ENC);
+}
+
+/*
+ * Remap memory with encryption and write-protected - cannot be called
+ * before pat_init() is called
+ */
+void __init *early_memremap_encrypted_wp(resource_size_t phys_addr,
+ unsigned long size)
+{
+ if (!x86_has_pat_wp())
+ return NULL;
+ return early_memremap_prot(phys_addr, size, __PAGE_KERNEL_ENC_WP);
+}
+
+/* Remap memory without encryption */
+void __init *early_memremap_decrypted(resource_size_t phys_addr,
+ unsigned long size)
+{
+ return early_memremap_prot(phys_addr, size, __PAGE_KERNEL_NOENC);
+}
+
+/*
+ * Remap memory without encryption and write-protected - cannot be called
+ * before pat_init() is called
+ */
+void __init *early_memremap_decrypted_wp(resource_size_t phys_addr,
+ unsigned long size)
+{
+ if (!x86_has_pat_wp())
+ return NULL;
+ return early_memremap_prot(phys_addr, size, __PAGE_KERNEL_NOENC_WP);
+}
+#endif /* CONFIG_AMD_MEM_ENCRYPT */
+
+static pte_t bm_pte[PAGE_SIZE/sizeof(pte_t)] __page_aligned_bss;
+
+static inline pmd_t * __init early_ioremap_pmd(unsigned long addr)
+{
+ /* Don't assume we're using swapper_pg_dir at this point */
+ pgd_t *base = __va(read_cr3_pa());
+ pgd_t *pgd = &base[pgd_index(addr)];
+ p4d_t *p4d = p4d_offset(pgd, addr);
+ pud_t *pud = pud_offset(p4d, addr);
+ pmd_t *pmd = pmd_offset(pud, addr);
+
+ return pmd;
+}
+
+static inline pte_t * __init early_ioremap_pte(unsigned long addr)
+{
+ return &bm_pte[pte_index(addr)];
+}
+
+bool __init is_early_ioremap_ptep(pte_t *ptep)
+{
+ return ptep >= &bm_pte[0] && ptep < &bm_pte[PAGE_SIZE/sizeof(pte_t)];
+}
+
+void __init early_ioremap_init(void)
+{
+ pmd_t *pmd;
+
+#ifdef CONFIG_X86_64
+ BUILD_BUG_ON((fix_to_virt(0) + PAGE_SIZE) & ((1 << PMD_SHIFT) - 1));
+#else
+ WARN_ON((fix_to_virt(0) + PAGE_SIZE) & ((1 << PMD_SHIFT) - 1));
+#endif
+
+ early_ioremap_setup();
+
+ pmd = early_ioremap_pmd(fix_to_virt(FIX_BTMAP_BEGIN));
+ memset(bm_pte, 0, sizeof(bm_pte));
+ pmd_populate_kernel(&init_mm, pmd, bm_pte);
+
+ /*
+ * The boot-ioremap range spans multiple pmds, for which
+ * we are not prepared:
+ */
+#define __FIXADDR_TOP (-PAGE_SIZE)
+ BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)
+ != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT));
+#undef __FIXADDR_TOP
+ if (pmd != early_ioremap_pmd(fix_to_virt(FIX_BTMAP_END))) {
+ WARN_ON(1);
+ printk(KERN_WARNING "pmd %p != %p\n",
+ pmd, early_ioremap_pmd(fix_to_virt(FIX_BTMAP_END)));
+ printk(KERN_WARNING "fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n",
+ fix_to_virt(FIX_BTMAP_BEGIN));
+ printk(KERN_WARNING "fix_to_virt(FIX_BTMAP_END): %08lx\n",
+ fix_to_virt(FIX_BTMAP_END));
+
+ printk(KERN_WARNING "FIX_BTMAP_END: %d\n", FIX_BTMAP_END);
+ printk(KERN_WARNING "FIX_BTMAP_BEGIN: %d\n",
+ FIX_BTMAP_BEGIN);
+ }
+}
+
+void __init __early_set_fixmap(enum fixed_addresses idx,
+ phys_addr_t phys, pgprot_t flags)
+{
+ unsigned long addr = __fix_to_virt(idx);
+ pte_t *pte;
+
+ if (idx >= __end_of_fixed_addresses) {
+ BUG();
+ return;
+ }
+ pte = early_ioremap_pte(addr);
+
+ /* Sanitize 'prot' against any unsupported bits: */
+ pgprot_val(flags) &= __supported_pte_mask;
+
+ if (pgprot_val(flags))
+ set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, flags));
+ else
+ pte_clear(&init_mm, addr, pte);
+ flush_tlb_one_kernel(addr);
+}