2f6474e463
Convert the XEN/PV hypercall to IDTENTRY: - Emit the ASM stub with DECLARE_IDTENTRY - Remove the ASM idtentry in 64-bit - Remove the open coded ASM entry code in 32-bit - Remove the old prototypes The handler stubs need to stay in ASM code as they need corner case handling and adjustment of the stack pointer. Provide a new C function which invokes the entry/exit handling and calls into the XEN handler on the interrupt stack if required. The exit code is slightly different from the regular idtentry_exit() on non-preemptible kernels. If the hypercall is preemptible and need_resched() is set then XEN provides a preempt hypercall scheduling function. Move this functionality into the entry code so it can use the existing idtentry functionality. [ mingo: Build fixes. ] Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Andy Lutomirski <luto@kernel.org> Acked-by: Juergen Gross <jgross@suse.com> Tested-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20200521202118.055270078@linutronix.de
1032 lines
28 KiB
C
1032 lines
28 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Machine specific setup for xen
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*
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* Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007
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*/
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#include <linux/init.h>
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#include <linux/sched.h>
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#include <linux/mm.h>
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#include <linux/pm.h>
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#include <linux/memblock.h>
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#include <linux/cpuidle.h>
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#include <linux/cpufreq.h>
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#include <linux/memory_hotplug.h>
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#include <asm/elf.h>
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#include <asm/vdso.h>
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#include <asm/e820/api.h>
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#include <asm/setup.h>
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#include <asm/acpi.h>
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#include <asm/numa.h>
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#include <asm/idtentry.h>
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#include <asm/xen/hypervisor.h>
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#include <asm/xen/hypercall.h>
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#include <xen/xen.h>
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#include <xen/page.h>
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#include <xen/interface/callback.h>
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#include <xen/interface/memory.h>
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#include <xen/interface/physdev.h>
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#include <xen/features.h>
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#include <xen/hvc-console.h>
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#include "xen-ops.h"
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#include "vdso.h"
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#include "mmu.h"
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#define GB(x) ((uint64_t)(x) * 1024 * 1024 * 1024)
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/* Amount of extra memory space we add to the e820 ranges */
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struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata;
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/* Number of pages released from the initial allocation. */
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unsigned long xen_released_pages;
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/* E820 map used during setting up memory. */
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static struct e820_table xen_e820_table __initdata;
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/*
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* Buffer used to remap identity mapped pages. We only need the virtual space.
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* The physical page behind this address is remapped as needed to different
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* buffer pages.
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*/
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#define REMAP_SIZE (P2M_PER_PAGE - 3)
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static struct {
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unsigned long next_area_mfn;
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unsigned long target_pfn;
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unsigned long size;
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unsigned long mfns[REMAP_SIZE];
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} xen_remap_buf __initdata __aligned(PAGE_SIZE);
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static unsigned long xen_remap_mfn __initdata = INVALID_P2M_ENTRY;
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/*
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* The maximum amount of extra memory compared to the base size. The
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* main scaling factor is the size of struct page. At extreme ratios
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* of base:extra, all the base memory can be filled with page
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* structures for the extra memory, leaving no space for anything
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* else.
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*
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* 10x seems like a reasonable balance between scaling flexibility and
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* leaving a practically usable system.
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*/
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#define EXTRA_MEM_RATIO (10)
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static bool xen_512gb_limit __initdata = IS_ENABLED(CONFIG_XEN_512GB);
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static void __init xen_parse_512gb(void)
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{
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bool val = false;
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char *arg;
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arg = strstr(xen_start_info->cmd_line, "xen_512gb_limit");
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if (!arg)
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return;
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arg = strstr(xen_start_info->cmd_line, "xen_512gb_limit=");
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if (!arg)
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val = true;
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else if (strtobool(arg + strlen("xen_512gb_limit="), &val))
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return;
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xen_512gb_limit = val;
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}
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static void __init xen_add_extra_mem(unsigned long start_pfn,
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unsigned long n_pfns)
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{
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int i;
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/*
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* No need to check for zero size, should happen rarely and will only
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* write a new entry regarded to be unused due to zero size.
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*/
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for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) {
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/* Add new region. */
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if (xen_extra_mem[i].n_pfns == 0) {
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xen_extra_mem[i].start_pfn = start_pfn;
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xen_extra_mem[i].n_pfns = n_pfns;
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break;
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}
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/* Append to existing region. */
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if (xen_extra_mem[i].start_pfn + xen_extra_mem[i].n_pfns ==
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start_pfn) {
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xen_extra_mem[i].n_pfns += n_pfns;
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break;
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}
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}
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if (i == XEN_EXTRA_MEM_MAX_REGIONS)
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printk(KERN_WARNING "Warning: not enough extra memory regions\n");
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memblock_reserve(PFN_PHYS(start_pfn), PFN_PHYS(n_pfns));
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}
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static void __init xen_del_extra_mem(unsigned long start_pfn,
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unsigned long n_pfns)
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{
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int i;
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unsigned long start_r, size_r;
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for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) {
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start_r = xen_extra_mem[i].start_pfn;
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size_r = xen_extra_mem[i].n_pfns;
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/* Start of region. */
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if (start_r == start_pfn) {
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BUG_ON(n_pfns > size_r);
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xen_extra_mem[i].start_pfn += n_pfns;
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xen_extra_mem[i].n_pfns -= n_pfns;
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break;
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}
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/* End of region. */
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if (start_r + size_r == start_pfn + n_pfns) {
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BUG_ON(n_pfns > size_r);
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xen_extra_mem[i].n_pfns -= n_pfns;
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break;
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}
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/* Mid of region. */
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if (start_pfn > start_r && start_pfn < start_r + size_r) {
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BUG_ON(start_pfn + n_pfns > start_r + size_r);
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xen_extra_mem[i].n_pfns = start_pfn - start_r;
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/* Calling memblock_reserve() again is okay. */
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xen_add_extra_mem(start_pfn + n_pfns, start_r + size_r -
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(start_pfn + n_pfns));
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break;
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}
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}
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memblock_free(PFN_PHYS(start_pfn), PFN_PHYS(n_pfns));
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}
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/*
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* Called during boot before the p2m list can take entries beyond the
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* hypervisor supplied p2m list. Entries in extra mem are to be regarded as
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* invalid.
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*/
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unsigned long __ref xen_chk_extra_mem(unsigned long pfn)
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{
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int i;
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for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) {
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if (pfn >= xen_extra_mem[i].start_pfn &&
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pfn < xen_extra_mem[i].start_pfn + xen_extra_mem[i].n_pfns)
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return INVALID_P2M_ENTRY;
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}
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return IDENTITY_FRAME(pfn);
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}
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/*
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* Mark all pfns of extra mem as invalid in p2m list.
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*/
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void __init xen_inv_extra_mem(void)
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{
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unsigned long pfn, pfn_s, pfn_e;
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int i;
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for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) {
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if (!xen_extra_mem[i].n_pfns)
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continue;
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pfn_s = xen_extra_mem[i].start_pfn;
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pfn_e = pfn_s + xen_extra_mem[i].n_pfns;
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for (pfn = pfn_s; pfn < pfn_e; pfn++)
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set_phys_to_machine(pfn, INVALID_P2M_ENTRY);
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}
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}
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/*
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* Finds the next RAM pfn available in the E820 map after min_pfn.
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* This function updates min_pfn with the pfn found and returns
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* the size of that range or zero if not found.
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*/
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static unsigned long __init xen_find_pfn_range(unsigned long *min_pfn)
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{
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const struct e820_entry *entry = xen_e820_table.entries;
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unsigned int i;
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unsigned long done = 0;
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for (i = 0; i < xen_e820_table.nr_entries; i++, entry++) {
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unsigned long s_pfn;
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unsigned long e_pfn;
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if (entry->type != E820_TYPE_RAM)
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continue;
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e_pfn = PFN_DOWN(entry->addr + entry->size);
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/* We only care about E820 after this */
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if (e_pfn <= *min_pfn)
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continue;
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s_pfn = PFN_UP(entry->addr);
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/* If min_pfn falls within the E820 entry, we want to start
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* at the min_pfn PFN.
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*/
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if (s_pfn <= *min_pfn) {
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done = e_pfn - *min_pfn;
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} else {
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done = e_pfn - s_pfn;
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*min_pfn = s_pfn;
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}
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break;
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}
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return done;
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}
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static int __init xen_free_mfn(unsigned long mfn)
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{
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struct xen_memory_reservation reservation = {
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.address_bits = 0,
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.extent_order = 0,
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.domid = DOMID_SELF
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};
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set_xen_guest_handle(reservation.extent_start, &mfn);
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reservation.nr_extents = 1;
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return HYPERVISOR_memory_op(XENMEM_decrease_reservation, &reservation);
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}
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/*
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* This releases a chunk of memory and then does the identity map. It's used
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* as a fallback if the remapping fails.
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*/
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static void __init xen_set_identity_and_release_chunk(unsigned long start_pfn,
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unsigned long end_pfn, unsigned long nr_pages)
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{
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unsigned long pfn, end;
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int ret;
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WARN_ON(start_pfn > end_pfn);
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/* Release pages first. */
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end = min(end_pfn, nr_pages);
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for (pfn = start_pfn; pfn < end; pfn++) {
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unsigned long mfn = pfn_to_mfn(pfn);
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/* Make sure pfn exists to start with */
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if (mfn == INVALID_P2M_ENTRY || mfn_to_pfn(mfn) != pfn)
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continue;
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ret = xen_free_mfn(mfn);
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WARN(ret != 1, "Failed to release pfn %lx err=%d\n", pfn, ret);
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if (ret == 1) {
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xen_released_pages++;
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if (!__set_phys_to_machine(pfn, INVALID_P2M_ENTRY))
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break;
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} else
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break;
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}
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set_phys_range_identity(start_pfn, end_pfn);
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}
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/*
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* Helper function to update the p2m and m2p tables and kernel mapping.
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*/
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static void __init xen_update_mem_tables(unsigned long pfn, unsigned long mfn)
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{
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struct mmu_update update = {
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.ptr = ((uint64_t)mfn << PAGE_SHIFT) | MMU_MACHPHYS_UPDATE,
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.val = pfn
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};
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/* Update p2m */
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if (!set_phys_to_machine(pfn, mfn)) {
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WARN(1, "Failed to set p2m mapping for pfn=%ld mfn=%ld\n",
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pfn, mfn);
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BUG();
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}
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/* Update m2p */
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if (HYPERVISOR_mmu_update(&update, 1, NULL, DOMID_SELF) < 0) {
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WARN(1, "Failed to set m2p mapping for mfn=%ld pfn=%ld\n",
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mfn, pfn);
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BUG();
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}
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/* Update kernel mapping, but not for highmem. */
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if (pfn >= PFN_UP(__pa(high_memory - 1)))
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return;
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if (HYPERVISOR_update_va_mapping((unsigned long)__va(pfn << PAGE_SHIFT),
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mfn_pte(mfn, PAGE_KERNEL), 0)) {
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WARN(1, "Failed to update kernel mapping for mfn=%ld pfn=%ld\n",
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mfn, pfn);
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BUG();
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}
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}
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/*
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* This function updates the p2m and m2p tables with an identity map from
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* start_pfn to start_pfn+size and prepares remapping the underlying RAM of the
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* original allocation at remap_pfn. The information needed for remapping is
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* saved in the memory itself to avoid the need for allocating buffers. The
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* complete remap information is contained in a list of MFNs each containing
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* up to REMAP_SIZE MFNs and the start target PFN for doing the remap.
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* This enables us to preserve the original mfn sequence while doing the
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* remapping at a time when the memory management is capable of allocating
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* virtual and physical memory in arbitrary amounts, see 'xen_remap_memory' and
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* its callers.
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*/
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static void __init xen_do_set_identity_and_remap_chunk(
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unsigned long start_pfn, unsigned long size, unsigned long remap_pfn)
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{
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unsigned long buf = (unsigned long)&xen_remap_buf;
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unsigned long mfn_save, mfn;
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unsigned long ident_pfn_iter, remap_pfn_iter;
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unsigned long ident_end_pfn = start_pfn + size;
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unsigned long left = size;
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unsigned int i, chunk;
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WARN_ON(size == 0);
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mfn_save = virt_to_mfn(buf);
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for (ident_pfn_iter = start_pfn, remap_pfn_iter = remap_pfn;
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ident_pfn_iter < ident_end_pfn;
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ident_pfn_iter += REMAP_SIZE, remap_pfn_iter += REMAP_SIZE) {
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chunk = (left < REMAP_SIZE) ? left : REMAP_SIZE;
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/* Map first pfn to xen_remap_buf */
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mfn = pfn_to_mfn(ident_pfn_iter);
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set_pte_mfn(buf, mfn, PAGE_KERNEL);
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/* Save mapping information in page */
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xen_remap_buf.next_area_mfn = xen_remap_mfn;
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xen_remap_buf.target_pfn = remap_pfn_iter;
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xen_remap_buf.size = chunk;
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for (i = 0; i < chunk; i++)
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xen_remap_buf.mfns[i] = pfn_to_mfn(ident_pfn_iter + i);
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/* Put remap buf into list. */
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xen_remap_mfn = mfn;
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/* Set identity map */
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set_phys_range_identity(ident_pfn_iter, ident_pfn_iter + chunk);
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left -= chunk;
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}
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/* Restore old xen_remap_buf mapping */
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set_pte_mfn(buf, mfn_save, PAGE_KERNEL);
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}
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/*
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* This function takes a contiguous pfn range that needs to be identity mapped
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* and:
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*
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* 1) Finds a new range of pfns to use to remap based on E820 and remap_pfn.
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* 2) Calls the do_ function to actually do the mapping/remapping work.
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*
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* The goal is to not allocate additional memory but to remap the existing
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* pages. In the case of an error the underlying memory is simply released back
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* to Xen and not remapped.
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*/
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static unsigned long __init xen_set_identity_and_remap_chunk(
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unsigned long start_pfn, unsigned long end_pfn, unsigned long nr_pages,
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unsigned long remap_pfn)
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{
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unsigned long pfn;
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unsigned long i = 0;
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unsigned long n = end_pfn - start_pfn;
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if (remap_pfn == 0)
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remap_pfn = nr_pages;
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while (i < n) {
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unsigned long cur_pfn = start_pfn + i;
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unsigned long left = n - i;
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unsigned long size = left;
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unsigned long remap_range_size;
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/* Do not remap pages beyond the current allocation */
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if (cur_pfn >= nr_pages) {
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/* Identity map remaining pages */
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set_phys_range_identity(cur_pfn, cur_pfn + size);
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break;
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}
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if (cur_pfn + size > nr_pages)
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size = nr_pages - cur_pfn;
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remap_range_size = xen_find_pfn_range(&remap_pfn);
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if (!remap_range_size) {
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pr_warn("Unable to find available pfn range, not remapping identity pages\n");
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xen_set_identity_and_release_chunk(cur_pfn,
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cur_pfn + left, nr_pages);
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break;
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}
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/* Adjust size to fit in current e820 RAM region */
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if (size > remap_range_size)
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size = remap_range_size;
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xen_do_set_identity_and_remap_chunk(cur_pfn, size, remap_pfn);
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/* Update variables to reflect new mappings. */
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i += size;
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remap_pfn += size;
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}
|
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|
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/*
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* If the PFNs are currently mapped, the VA mapping also needs
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* to be updated to be 1:1.
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*/
|
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for (pfn = start_pfn; pfn <= max_pfn_mapped && pfn < end_pfn; pfn++)
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(void)HYPERVISOR_update_va_mapping(
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(unsigned long)__va(pfn << PAGE_SHIFT),
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mfn_pte(pfn, PAGE_KERNEL_IO), 0);
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return remap_pfn;
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}
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static unsigned long __init xen_count_remap_pages(
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unsigned long start_pfn, unsigned long end_pfn, unsigned long nr_pages,
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unsigned long remap_pages)
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{
|
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if (start_pfn >= nr_pages)
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return remap_pages;
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return remap_pages + min(end_pfn, nr_pages) - start_pfn;
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}
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static unsigned long __init xen_foreach_remap_area(unsigned long nr_pages,
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unsigned long (*func)(unsigned long start_pfn, unsigned long end_pfn,
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unsigned long nr_pages, unsigned long last_val))
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{
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phys_addr_t start = 0;
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unsigned long ret_val = 0;
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const struct e820_entry *entry = xen_e820_table.entries;
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int i;
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/*
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* Combine non-RAM regions and gaps until a RAM region (or the
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* end of the map) is reached, then call the provided function
|
|
* to perform its duty on the non-RAM region.
|
|
*
|
|
* The combined non-RAM regions are rounded to a whole number
|
|
* of pages so any partial pages are accessible via the 1:1
|
|
* mapping. This is needed for some BIOSes that put (for
|
|
* example) the DMI tables in a reserved region that begins on
|
|
* a non-page boundary.
|
|
*/
|
|
for (i = 0; i < xen_e820_table.nr_entries; i++, entry++) {
|
|
phys_addr_t end = entry->addr + entry->size;
|
|
if (entry->type == E820_TYPE_RAM || i == xen_e820_table.nr_entries - 1) {
|
|
unsigned long start_pfn = PFN_DOWN(start);
|
|
unsigned long end_pfn = PFN_UP(end);
|
|
|
|
if (entry->type == E820_TYPE_RAM)
|
|
end_pfn = PFN_UP(entry->addr);
|
|
|
|
if (start_pfn < end_pfn)
|
|
ret_val = func(start_pfn, end_pfn, nr_pages,
|
|
ret_val);
|
|
start = end;
|
|
}
|
|
}
|
|
|
|
return ret_val;
|
|
}
|
|
|
|
/*
|
|
* Remap the memory prepared in xen_do_set_identity_and_remap_chunk().
|
|
* The remap information (which mfn remap to which pfn) is contained in the
|
|
* to be remapped memory itself in a linked list anchored at xen_remap_mfn.
|
|
* This scheme allows to remap the different chunks in arbitrary order while
|
|
* the resulting mapping will be independent from the order.
|
|
*/
|
|
void __init xen_remap_memory(void)
|
|
{
|
|
unsigned long buf = (unsigned long)&xen_remap_buf;
|
|
unsigned long mfn_save, pfn;
|
|
unsigned long remapped = 0;
|
|
unsigned int i;
|
|
unsigned long pfn_s = ~0UL;
|
|
unsigned long len = 0;
|
|
|
|
mfn_save = virt_to_mfn(buf);
|
|
|
|
while (xen_remap_mfn != INVALID_P2M_ENTRY) {
|
|
/* Map the remap information */
|
|
set_pte_mfn(buf, xen_remap_mfn, PAGE_KERNEL);
|
|
|
|
BUG_ON(xen_remap_mfn != xen_remap_buf.mfns[0]);
|
|
|
|
pfn = xen_remap_buf.target_pfn;
|
|
for (i = 0; i < xen_remap_buf.size; i++) {
|
|
xen_update_mem_tables(pfn, xen_remap_buf.mfns[i]);
|
|
remapped++;
|
|
pfn++;
|
|
}
|
|
if (pfn_s == ~0UL || pfn == pfn_s) {
|
|
pfn_s = xen_remap_buf.target_pfn;
|
|
len += xen_remap_buf.size;
|
|
} else if (pfn_s + len == xen_remap_buf.target_pfn) {
|
|
len += xen_remap_buf.size;
|
|
} else {
|
|
xen_del_extra_mem(pfn_s, len);
|
|
pfn_s = xen_remap_buf.target_pfn;
|
|
len = xen_remap_buf.size;
|
|
}
|
|
xen_remap_mfn = xen_remap_buf.next_area_mfn;
|
|
}
|
|
|
|
if (pfn_s != ~0UL && len)
|
|
xen_del_extra_mem(pfn_s, len);
|
|
|
|
set_pte_mfn(buf, mfn_save, PAGE_KERNEL);
|
|
|
|
pr_info("Remapped %ld page(s)\n", remapped);
|
|
}
|
|
|
|
static unsigned long __init xen_get_pages_limit(void)
|
|
{
|
|
unsigned long limit;
|
|
|
|
#ifdef CONFIG_X86_32
|
|
limit = GB(64) / PAGE_SIZE;
|
|
#else
|
|
limit = MAXMEM / PAGE_SIZE;
|
|
if (!xen_initial_domain() && xen_512gb_limit)
|
|
limit = GB(512) / PAGE_SIZE;
|
|
#endif
|
|
return limit;
|
|
}
|
|
|
|
static unsigned long __init xen_get_max_pages(void)
|
|
{
|
|
unsigned long max_pages, limit;
|
|
domid_t domid = DOMID_SELF;
|
|
long ret;
|
|
|
|
limit = xen_get_pages_limit();
|
|
max_pages = limit;
|
|
|
|
/*
|
|
* For the initial domain we use the maximum reservation as
|
|
* the maximum page.
|
|
*
|
|
* For guest domains the current maximum reservation reflects
|
|
* the current maximum rather than the static maximum. In this
|
|
* case the e820 map provided to us will cover the static
|
|
* maximum region.
|
|
*/
|
|
if (xen_initial_domain()) {
|
|
ret = HYPERVISOR_memory_op(XENMEM_maximum_reservation, &domid);
|
|
if (ret > 0)
|
|
max_pages = ret;
|
|
}
|
|
|
|
return min(max_pages, limit);
|
|
}
|
|
|
|
static void __init xen_align_and_add_e820_region(phys_addr_t start,
|
|
phys_addr_t size, int type)
|
|
{
|
|
phys_addr_t end = start + size;
|
|
|
|
/* Align RAM regions to page boundaries. */
|
|
if (type == E820_TYPE_RAM) {
|
|
start = PAGE_ALIGN(start);
|
|
end &= ~((phys_addr_t)PAGE_SIZE - 1);
|
|
#ifdef CONFIG_MEMORY_HOTPLUG
|
|
/*
|
|
* Don't allow adding memory not in E820 map while booting the
|
|
* system. Once the balloon driver is up it will remove that
|
|
* restriction again.
|
|
*/
|
|
max_mem_size = end;
|
|
#endif
|
|
}
|
|
|
|
e820__range_add(start, end - start, type);
|
|
}
|
|
|
|
static void __init xen_ignore_unusable(void)
|
|
{
|
|
struct e820_entry *entry = xen_e820_table.entries;
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < xen_e820_table.nr_entries; i++, entry++) {
|
|
if (entry->type == E820_TYPE_UNUSABLE)
|
|
entry->type = E820_TYPE_RAM;
|
|
}
|
|
}
|
|
|
|
bool __init xen_is_e820_reserved(phys_addr_t start, phys_addr_t size)
|
|
{
|
|
struct e820_entry *entry;
|
|
unsigned mapcnt;
|
|
phys_addr_t end;
|
|
|
|
if (!size)
|
|
return false;
|
|
|
|
end = start + size;
|
|
entry = xen_e820_table.entries;
|
|
|
|
for (mapcnt = 0; mapcnt < xen_e820_table.nr_entries; mapcnt++) {
|
|
if (entry->type == E820_TYPE_RAM && entry->addr <= start &&
|
|
(entry->addr + entry->size) >= end)
|
|
return false;
|
|
|
|
entry++;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Find a free area in physical memory not yet reserved and compliant with
|
|
* E820 map.
|
|
* Used to relocate pre-allocated areas like initrd or p2m list which are in
|
|
* conflict with the to be used E820 map.
|
|
* In case no area is found, return 0. Otherwise return the physical address
|
|
* of the area which is already reserved for convenience.
|
|
*/
|
|
phys_addr_t __init xen_find_free_area(phys_addr_t size)
|
|
{
|
|
unsigned mapcnt;
|
|
phys_addr_t addr, start;
|
|
struct e820_entry *entry = xen_e820_table.entries;
|
|
|
|
for (mapcnt = 0; mapcnt < xen_e820_table.nr_entries; mapcnt++, entry++) {
|
|
if (entry->type != E820_TYPE_RAM || entry->size < size)
|
|
continue;
|
|
start = entry->addr;
|
|
for (addr = start; addr < start + size; addr += PAGE_SIZE) {
|
|
if (!memblock_is_reserved(addr))
|
|
continue;
|
|
start = addr + PAGE_SIZE;
|
|
if (start + size > entry->addr + entry->size)
|
|
break;
|
|
}
|
|
if (addr >= start + size) {
|
|
memblock_reserve(start, size);
|
|
return start;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Like memcpy, but with physical addresses for dest and src.
|
|
*/
|
|
static void __init xen_phys_memcpy(phys_addr_t dest, phys_addr_t src,
|
|
phys_addr_t n)
|
|
{
|
|
phys_addr_t dest_off, src_off, dest_len, src_len, len;
|
|
void *from, *to;
|
|
|
|
while (n) {
|
|
dest_off = dest & ~PAGE_MASK;
|
|
src_off = src & ~PAGE_MASK;
|
|
dest_len = n;
|
|
if (dest_len > (NR_FIX_BTMAPS << PAGE_SHIFT) - dest_off)
|
|
dest_len = (NR_FIX_BTMAPS << PAGE_SHIFT) - dest_off;
|
|
src_len = n;
|
|
if (src_len > (NR_FIX_BTMAPS << PAGE_SHIFT) - src_off)
|
|
src_len = (NR_FIX_BTMAPS << PAGE_SHIFT) - src_off;
|
|
len = min(dest_len, src_len);
|
|
to = early_memremap(dest - dest_off, dest_len + dest_off);
|
|
from = early_memremap(src - src_off, src_len + src_off);
|
|
memcpy(to, from, len);
|
|
early_memunmap(to, dest_len + dest_off);
|
|
early_memunmap(from, src_len + src_off);
|
|
n -= len;
|
|
dest += len;
|
|
src += len;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Reserve Xen mfn_list.
|
|
*/
|
|
static void __init xen_reserve_xen_mfnlist(void)
|
|
{
|
|
phys_addr_t start, size;
|
|
|
|
if (xen_start_info->mfn_list >= __START_KERNEL_map) {
|
|
start = __pa(xen_start_info->mfn_list);
|
|
size = PFN_ALIGN(xen_start_info->nr_pages *
|
|
sizeof(unsigned long));
|
|
} else {
|
|
start = PFN_PHYS(xen_start_info->first_p2m_pfn);
|
|
size = PFN_PHYS(xen_start_info->nr_p2m_frames);
|
|
}
|
|
|
|
memblock_reserve(start, size);
|
|
if (!xen_is_e820_reserved(start, size))
|
|
return;
|
|
|
|
#ifdef CONFIG_X86_32
|
|
/*
|
|
* Relocating the p2m on 32 bit system to an arbitrary virtual address
|
|
* is not supported, so just give up.
|
|
*/
|
|
xen_raw_console_write("Xen hypervisor allocated p2m list conflicts with E820 map\n");
|
|
BUG();
|
|
#else
|
|
xen_relocate_p2m();
|
|
memblock_free(start, size);
|
|
#endif
|
|
}
|
|
|
|
/**
|
|
* machine_specific_memory_setup - Hook for machine specific memory setup.
|
|
**/
|
|
char * __init xen_memory_setup(void)
|
|
{
|
|
unsigned long max_pfn, pfn_s, n_pfns;
|
|
phys_addr_t mem_end, addr, size, chunk_size;
|
|
u32 type;
|
|
int rc;
|
|
struct xen_memory_map memmap;
|
|
unsigned long max_pages;
|
|
unsigned long extra_pages = 0;
|
|
int i;
|
|
int op;
|
|
|
|
xen_parse_512gb();
|
|
max_pfn = xen_get_pages_limit();
|
|
max_pfn = min(max_pfn, xen_start_info->nr_pages);
|
|
mem_end = PFN_PHYS(max_pfn);
|
|
|
|
memmap.nr_entries = ARRAY_SIZE(xen_e820_table.entries);
|
|
set_xen_guest_handle(memmap.buffer, xen_e820_table.entries);
|
|
|
|
#if defined(CONFIG_MEMORY_HOTPLUG) && defined(CONFIG_XEN_BALLOON)
|
|
xen_saved_max_mem_size = max_mem_size;
|
|
#endif
|
|
|
|
op = xen_initial_domain() ?
|
|
XENMEM_machine_memory_map :
|
|
XENMEM_memory_map;
|
|
rc = HYPERVISOR_memory_op(op, &memmap);
|
|
if (rc == -ENOSYS) {
|
|
BUG_ON(xen_initial_domain());
|
|
memmap.nr_entries = 1;
|
|
xen_e820_table.entries[0].addr = 0ULL;
|
|
xen_e820_table.entries[0].size = mem_end;
|
|
/* 8MB slack (to balance backend allocations). */
|
|
xen_e820_table.entries[0].size += 8ULL << 20;
|
|
xen_e820_table.entries[0].type = E820_TYPE_RAM;
|
|
rc = 0;
|
|
}
|
|
BUG_ON(rc);
|
|
BUG_ON(memmap.nr_entries == 0);
|
|
xen_e820_table.nr_entries = memmap.nr_entries;
|
|
|
|
/*
|
|
* Xen won't allow a 1:1 mapping to be created to UNUSABLE
|
|
* regions, so if we're using the machine memory map leave the
|
|
* region as RAM as it is in the pseudo-physical map.
|
|
*
|
|
* UNUSABLE regions in domUs are not handled and will need
|
|
* a patch in the future.
|
|
*/
|
|
if (xen_initial_domain())
|
|
xen_ignore_unusable();
|
|
|
|
/* Make sure the Xen-supplied memory map is well-ordered. */
|
|
e820__update_table(&xen_e820_table);
|
|
|
|
max_pages = xen_get_max_pages();
|
|
|
|
/* How many extra pages do we need due to remapping? */
|
|
max_pages += xen_foreach_remap_area(max_pfn, xen_count_remap_pages);
|
|
|
|
if (max_pages > max_pfn)
|
|
extra_pages += max_pages - max_pfn;
|
|
|
|
/*
|
|
* Clamp the amount of extra memory to a EXTRA_MEM_RATIO
|
|
* factor the base size. On non-highmem systems, the base
|
|
* size is the full initial memory allocation; on highmem it
|
|
* is limited to the max size of lowmem, so that it doesn't
|
|
* get completely filled.
|
|
*
|
|
* Make sure we have no memory above max_pages, as this area
|
|
* isn't handled by the p2m management.
|
|
*
|
|
* In principle there could be a problem in lowmem systems if
|
|
* the initial memory is also very large with respect to
|
|
* lowmem, but we won't try to deal with that here.
|
|
*/
|
|
extra_pages = min3(EXTRA_MEM_RATIO * min(max_pfn, PFN_DOWN(MAXMEM)),
|
|
extra_pages, max_pages - max_pfn);
|
|
i = 0;
|
|
addr = xen_e820_table.entries[0].addr;
|
|
size = xen_e820_table.entries[0].size;
|
|
while (i < xen_e820_table.nr_entries) {
|
|
bool discard = false;
|
|
|
|
chunk_size = size;
|
|
type = xen_e820_table.entries[i].type;
|
|
|
|
if (type == E820_TYPE_RAM) {
|
|
if (addr < mem_end) {
|
|
chunk_size = min(size, mem_end - addr);
|
|
} else if (extra_pages) {
|
|
chunk_size = min(size, PFN_PHYS(extra_pages));
|
|
pfn_s = PFN_UP(addr);
|
|
n_pfns = PFN_DOWN(addr + chunk_size) - pfn_s;
|
|
extra_pages -= n_pfns;
|
|
xen_add_extra_mem(pfn_s, n_pfns);
|
|
xen_max_p2m_pfn = pfn_s + n_pfns;
|
|
} else
|
|
discard = true;
|
|
}
|
|
|
|
if (!discard)
|
|
xen_align_and_add_e820_region(addr, chunk_size, type);
|
|
|
|
addr += chunk_size;
|
|
size -= chunk_size;
|
|
if (size == 0) {
|
|
i++;
|
|
if (i < xen_e820_table.nr_entries) {
|
|
addr = xen_e820_table.entries[i].addr;
|
|
size = xen_e820_table.entries[i].size;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Set the rest as identity mapped, in case PCI BARs are
|
|
* located here.
|
|
*/
|
|
set_phys_range_identity(addr / PAGE_SIZE, ~0ul);
|
|
|
|
/*
|
|
* In domU, the ISA region is normal, usable memory, but we
|
|
* reserve ISA memory anyway because too many things poke
|
|
* about in there.
|
|
*/
|
|
e820__range_add(ISA_START_ADDRESS, ISA_END_ADDRESS - ISA_START_ADDRESS, E820_TYPE_RESERVED);
|
|
|
|
e820__update_table(e820_table);
|
|
|
|
/*
|
|
* Check whether the kernel itself conflicts with the target E820 map.
|
|
* Failing now is better than running into weird problems later due
|
|
* to relocating (and even reusing) pages with kernel text or data.
|
|
*/
|
|
if (xen_is_e820_reserved(__pa_symbol(_text),
|
|
__pa_symbol(__bss_stop) - __pa_symbol(_text))) {
|
|
xen_raw_console_write("Xen hypervisor allocated kernel memory conflicts with E820 map\n");
|
|
BUG();
|
|
}
|
|
|
|
/*
|
|
* Check for a conflict of the hypervisor supplied page tables with
|
|
* the target E820 map.
|
|
*/
|
|
xen_pt_check_e820();
|
|
|
|
xen_reserve_xen_mfnlist();
|
|
|
|
/* Check for a conflict of the initrd with the target E820 map. */
|
|
if (xen_is_e820_reserved(boot_params.hdr.ramdisk_image,
|
|
boot_params.hdr.ramdisk_size)) {
|
|
phys_addr_t new_area, start, size;
|
|
|
|
new_area = xen_find_free_area(boot_params.hdr.ramdisk_size);
|
|
if (!new_area) {
|
|
xen_raw_console_write("Can't find new memory area for initrd needed due to E820 map conflict\n");
|
|
BUG();
|
|
}
|
|
|
|
start = boot_params.hdr.ramdisk_image;
|
|
size = boot_params.hdr.ramdisk_size;
|
|
xen_phys_memcpy(new_area, start, size);
|
|
pr_info("initrd moved from [mem %#010llx-%#010llx] to [mem %#010llx-%#010llx]\n",
|
|
start, start + size, new_area, new_area + size);
|
|
memblock_free(start, size);
|
|
boot_params.hdr.ramdisk_image = new_area;
|
|
boot_params.ext_ramdisk_image = new_area >> 32;
|
|
}
|
|
|
|
/*
|
|
* Set identity map on non-RAM pages and prepare remapping the
|
|
* underlying RAM.
|
|
*/
|
|
xen_foreach_remap_area(max_pfn, xen_set_identity_and_remap_chunk);
|
|
|
|
pr_info("Released %ld page(s)\n", xen_released_pages);
|
|
|
|
return "Xen";
|
|
}
|
|
|
|
/*
|
|
* Set the bit indicating "nosegneg" library variants should be used.
|
|
* We only need to bother in pure 32-bit mode; compat 32-bit processes
|
|
* can have un-truncated segments, so wrapping around is allowed.
|
|
*/
|
|
static void __init fiddle_vdso(void)
|
|
{
|
|
#ifdef CONFIG_X86_32
|
|
u32 *mask = vdso_image_32.data +
|
|
vdso_image_32.sym_VDSO32_NOTE_MASK;
|
|
*mask |= 1 << VDSO_NOTE_NONEGSEG_BIT;
|
|
#endif
|
|
}
|
|
|
|
static int register_callback(unsigned type, const void *func)
|
|
{
|
|
struct callback_register callback = {
|
|
.type = type,
|
|
.address = XEN_CALLBACK(__KERNEL_CS, func),
|
|
.flags = CALLBACKF_mask_events,
|
|
};
|
|
|
|
return HYPERVISOR_callback_op(CALLBACKOP_register, &callback);
|
|
}
|
|
|
|
void xen_enable_sysenter(void)
|
|
{
|
|
int ret;
|
|
unsigned sysenter_feature;
|
|
|
|
#ifdef CONFIG_X86_32
|
|
sysenter_feature = X86_FEATURE_SEP;
|
|
#else
|
|
sysenter_feature = X86_FEATURE_SYSENTER32;
|
|
#endif
|
|
|
|
if (!boot_cpu_has(sysenter_feature))
|
|
return;
|
|
|
|
ret = register_callback(CALLBACKTYPE_sysenter, xen_sysenter_target);
|
|
if(ret != 0)
|
|
setup_clear_cpu_cap(sysenter_feature);
|
|
}
|
|
|
|
void xen_enable_syscall(void)
|
|
{
|
|
#ifdef CONFIG_X86_64
|
|
int ret;
|
|
|
|
ret = register_callback(CALLBACKTYPE_syscall, xen_syscall_target);
|
|
if (ret != 0) {
|
|
printk(KERN_ERR "Failed to set syscall callback: %d\n", ret);
|
|
/* Pretty fatal; 64-bit userspace has no other
|
|
mechanism for syscalls. */
|
|
}
|
|
|
|
if (boot_cpu_has(X86_FEATURE_SYSCALL32)) {
|
|
ret = register_callback(CALLBACKTYPE_syscall32,
|
|
xen_syscall32_target);
|
|
if (ret != 0)
|
|
setup_clear_cpu_cap(X86_FEATURE_SYSCALL32);
|
|
}
|
|
#endif /* CONFIG_X86_64 */
|
|
}
|
|
|
|
static void __init xen_pvmmu_arch_setup(void)
|
|
{
|
|
HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_4gb_segments);
|
|
HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_writable_pagetables);
|
|
|
|
HYPERVISOR_vm_assist(VMASST_CMD_enable,
|
|
VMASST_TYPE_pae_extended_cr3);
|
|
|
|
if (register_callback(CALLBACKTYPE_event,
|
|
xen_asm_exc_xen_hypervisor_callback) ||
|
|
register_callback(CALLBACKTYPE_failsafe, xen_failsafe_callback))
|
|
BUG();
|
|
|
|
xen_enable_sysenter();
|
|
xen_enable_syscall();
|
|
}
|
|
|
|
/* This function is not called for HVM domains */
|
|
void __init xen_arch_setup(void)
|
|
{
|
|
xen_panic_handler_init();
|
|
xen_pvmmu_arch_setup();
|
|
|
|
#ifdef CONFIG_ACPI
|
|
if (!(xen_start_info->flags & SIF_INITDOMAIN)) {
|
|
printk(KERN_INFO "ACPI in unprivileged domain disabled\n");
|
|
disable_acpi();
|
|
}
|
|
#endif
|
|
|
|
memcpy(boot_command_line, xen_start_info->cmd_line,
|
|
MAX_GUEST_CMDLINE > COMMAND_LINE_SIZE ?
|
|
COMMAND_LINE_SIZE : MAX_GUEST_CMDLINE);
|
|
|
|
/* Set up idle, making sure it calls safe_halt() pvop */
|
|
disable_cpuidle();
|
|
disable_cpufreq();
|
|
WARN_ON(xen_set_default_idle());
|
|
fiddle_vdso();
|
|
#ifdef CONFIG_NUMA
|
|
numa_off = 1;
|
|
#endif
|
|
}
|