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Diffstat (limited to 'kernel/arch/x86/xen/setup.c')
| -rw-r--r-- | kernel/arch/x86/xen/setup.c | 864 |
1 files changed, 864 insertions, 0 deletions
diff --git a/kernel/arch/x86/xen/setup.c b/kernel/arch/x86/xen/setup.c new file mode 100644 index 000000000..55f388ef4 --- /dev/null +++ b/kernel/arch/x86/xen/setup.c @@ -0,0 +1,864 @@ +/* + * Machine specific setup for xen + * + * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007 + */ + +#include <linux/module.h> +#include <linux/sched.h> +#include <linux/mm.h> +#include <linux/pm.h> +#include <linux/memblock.h> +#include <linux/cpuidle.h> +#include <linux/cpufreq.h> + +#include <asm/elf.h> +#include <asm/vdso.h> +#include <asm/e820.h> +#include <asm/setup.h> +#include <asm/acpi.h> +#include <asm/numa.h> +#include <asm/xen/hypervisor.h> +#include <asm/xen/hypercall.h> + +#include <xen/xen.h> +#include <xen/page.h> +#include <xen/interface/callback.h> +#include <xen/interface/memory.h> +#include <xen/interface/physdev.h> +#include <xen/features.h> +#include "xen-ops.h" +#include "vdso.h" +#include "p2m.h" +#include "mmu.h" + +/* Amount of extra memory space we add to the e820 ranges */ +struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata; + +/* Number of pages released from the initial allocation. */ +unsigned long xen_released_pages; + +/* + * Buffer used to remap identity mapped pages. We only need the virtual space. + * The physical page behind this address is remapped as needed to different + * buffer pages. + */ +#define REMAP_SIZE (P2M_PER_PAGE - 3) +static struct { + unsigned long next_area_mfn; + unsigned long target_pfn; + unsigned long size; + unsigned long mfns[REMAP_SIZE]; +} xen_remap_buf __initdata __aligned(PAGE_SIZE); +static unsigned long xen_remap_mfn __initdata = INVALID_P2M_ENTRY; + +/* + * The maximum amount of extra memory compared to the base size. The + * main scaling factor is the size of struct page. At extreme ratios + * of base:extra, all the base memory can be filled with page + * structures for the extra memory, leaving no space for anything + * else. + * + * 10x seems like a reasonable balance between scaling flexibility and + * leaving a practically usable system. + */ +#define EXTRA_MEM_RATIO (10) + +static void __init xen_add_extra_mem(phys_addr_t start, phys_addr_t size) +{ + int i; + + for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) { + /* Add new region. */ + if (xen_extra_mem[i].size == 0) { + xen_extra_mem[i].start = start; + xen_extra_mem[i].size = size; + break; + } + /* Append to existing region. */ + if (xen_extra_mem[i].start + xen_extra_mem[i].size == start) { + xen_extra_mem[i].size += size; + break; + } + } + if (i == XEN_EXTRA_MEM_MAX_REGIONS) + printk(KERN_WARNING "Warning: not enough extra memory regions\n"); + + memblock_reserve(start, size); +} + +static void __init xen_del_extra_mem(phys_addr_t start, phys_addr_t size) +{ + int i; + phys_addr_t start_r, size_r; + + for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) { + start_r = xen_extra_mem[i].start; + size_r = xen_extra_mem[i].size; + + /* Start of region. */ + if (start_r == start) { + BUG_ON(size > size_r); + xen_extra_mem[i].start += size; + xen_extra_mem[i].size -= size; + break; + } + /* End of region. */ + if (start_r + size_r == start + size) { + BUG_ON(size > size_r); + xen_extra_mem[i].size -= size; + break; + } + /* Mid of region. */ + if (start > start_r && start < start_r + size_r) { + BUG_ON(start + size > start_r + size_r); + xen_extra_mem[i].size = start - start_r; + /* Calling memblock_reserve() again is okay. */ + xen_add_extra_mem(start + size, start_r + size_r - + (start + size)); + break; + } + } + memblock_free(start, size); +} + +/* + * Called during boot before the p2m list can take entries beyond the + * hypervisor supplied p2m list. Entries in extra mem are to be regarded as + * invalid. + */ +unsigned long __ref xen_chk_extra_mem(unsigned long pfn) +{ + int i; + phys_addr_t addr = PFN_PHYS(pfn); + + for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) { + if (addr >= xen_extra_mem[i].start && + addr < xen_extra_mem[i].start + xen_extra_mem[i].size) + return INVALID_P2M_ENTRY; + } + + return IDENTITY_FRAME(pfn); +} + +/* + * Mark all pfns of extra mem as invalid in p2m list. + */ +void __init xen_inv_extra_mem(void) +{ + unsigned long pfn, pfn_s, pfn_e; + int i; + + for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) { + if (!xen_extra_mem[i].size) + continue; + pfn_s = PFN_DOWN(xen_extra_mem[i].start); + pfn_e = PFN_UP(xen_extra_mem[i].start + xen_extra_mem[i].size); + for (pfn = pfn_s; pfn < pfn_e; pfn++) + set_phys_to_machine(pfn, INVALID_P2M_ENTRY); + } +} + +/* + * Finds the next RAM pfn available in the E820 map after min_pfn. + * This function updates min_pfn with the pfn found and returns + * the size of that range or zero if not found. + */ +static unsigned long __init xen_find_pfn_range( + const struct e820entry *list, size_t map_size, + unsigned long *min_pfn) +{ + const struct e820entry *entry; + unsigned int i; + unsigned long done = 0; + + for (i = 0, entry = list; i < map_size; i++, entry++) { + unsigned long s_pfn; + unsigned long e_pfn; + + if (entry->type != E820_RAM) + continue; + + e_pfn = PFN_DOWN(entry->addr + entry->size); + + /* We only care about E820 after this */ + if (e_pfn < *min_pfn) + continue; + + s_pfn = PFN_UP(entry->addr); + + /* If min_pfn falls within the E820 entry, we want to start + * at the min_pfn PFN. + */ + if (s_pfn <= *min_pfn) { + done = e_pfn - *min_pfn; + } else { + done = e_pfn - s_pfn; + *min_pfn = s_pfn; + } + break; + } + + return done; +} + +static int __init xen_free_mfn(unsigned long mfn) +{ + struct xen_memory_reservation reservation = { + .address_bits = 0, + .extent_order = 0, + .domid = DOMID_SELF + }; + + set_xen_guest_handle(reservation.extent_start, &mfn); + reservation.nr_extents = 1; + + return HYPERVISOR_memory_op(XENMEM_decrease_reservation, &reservation); +} + +/* + * This releases a chunk of memory and then does the identity map. It's used + * as a fallback if the remapping fails. + */ +static void __init xen_set_identity_and_release_chunk(unsigned long start_pfn, + unsigned long end_pfn, unsigned long nr_pages, unsigned long *released) +{ + unsigned long pfn, end; + int ret; + + WARN_ON(start_pfn > end_pfn); + + /* Release pages first. */ + end = min(end_pfn, nr_pages); + for (pfn = start_pfn; pfn < end; pfn++) { + unsigned long mfn = pfn_to_mfn(pfn); + + /* Make sure pfn exists to start with */ + if (mfn == INVALID_P2M_ENTRY || mfn_to_pfn(mfn) != pfn) + continue; + + ret = xen_free_mfn(mfn); + WARN(ret != 1, "Failed to release pfn %lx err=%d\n", pfn, ret); + + if (ret == 1) { + (*released)++; + if (!__set_phys_to_machine(pfn, INVALID_P2M_ENTRY)) + break; + } else + break; + } + + set_phys_range_identity(start_pfn, end_pfn); +} + +/* + * Helper function to update the p2m and m2p tables and kernel mapping. + */ +static void __init xen_update_mem_tables(unsigned long pfn, unsigned long mfn) +{ + struct mmu_update update = { + .ptr = ((uint64_t)mfn << PAGE_SHIFT) | MMU_MACHPHYS_UPDATE, + .val = pfn + }; + + /* Update p2m */ + if (!set_phys_to_machine(pfn, mfn)) { + WARN(1, "Failed to set p2m mapping for pfn=%ld mfn=%ld\n", + pfn, mfn); + BUG(); + } + + /* Update m2p */ + if (HYPERVISOR_mmu_update(&update, 1, NULL, DOMID_SELF) < 0) { + WARN(1, "Failed to set m2p mapping for mfn=%ld pfn=%ld\n", + mfn, pfn); + BUG(); + } + + /* Update kernel mapping, but not for highmem. */ + if (pfn >= PFN_UP(__pa(high_memory - 1))) + return; + + if (HYPERVISOR_update_va_mapping((unsigned long)__va(pfn << PAGE_SHIFT), + mfn_pte(mfn, PAGE_KERNEL), 0)) { + WARN(1, "Failed to update kernel mapping for mfn=%ld pfn=%ld\n", + mfn, pfn); + BUG(); + } +} + +/* + * This function updates the p2m and m2p tables with an identity map from + * start_pfn to start_pfn+size and prepares remapping the underlying RAM of the + * original allocation at remap_pfn. The information needed for remapping is + * saved in the memory itself to avoid the need for allocating buffers. The + * complete remap information is contained in a list of MFNs each containing + * up to REMAP_SIZE MFNs and the start target PFN for doing the remap. + * This enables us to preserve the original mfn sequence while doing the + * remapping at a time when the memory management is capable of allocating + * virtual and physical memory in arbitrary amounts, see 'xen_remap_memory' and + * its callers. + */ +static void __init xen_do_set_identity_and_remap_chunk( + unsigned long start_pfn, unsigned long size, unsigned long remap_pfn) +{ + unsigned long buf = (unsigned long)&xen_remap_buf; + unsigned long mfn_save, mfn; + unsigned long ident_pfn_iter, remap_pfn_iter; + unsigned long ident_end_pfn = start_pfn + size; + unsigned long left = size; + unsigned int i, chunk; + + WARN_ON(size == 0); + + BUG_ON(xen_feature(XENFEAT_auto_translated_physmap)); + + mfn_save = virt_to_mfn(buf); + + for (ident_pfn_iter = start_pfn, remap_pfn_iter = remap_pfn; + ident_pfn_iter < ident_end_pfn; + ident_pfn_iter += REMAP_SIZE, remap_pfn_iter += REMAP_SIZE) { + chunk = (left < REMAP_SIZE) ? left : REMAP_SIZE; + + /* Map first pfn to xen_remap_buf */ + mfn = pfn_to_mfn(ident_pfn_iter); + set_pte_mfn(buf, mfn, PAGE_KERNEL); + + /* Save mapping information in page */ + xen_remap_buf.next_area_mfn = xen_remap_mfn; + xen_remap_buf.target_pfn = remap_pfn_iter; + xen_remap_buf.size = chunk; + for (i = 0; i < chunk; i++) + xen_remap_buf.mfns[i] = pfn_to_mfn(ident_pfn_iter + i); + + /* Put remap buf into list. */ + xen_remap_mfn = mfn; + + /* Set identity map */ + set_phys_range_identity(ident_pfn_iter, ident_pfn_iter + chunk); + + left -= chunk; + } + + /* Restore old xen_remap_buf mapping */ + set_pte_mfn(buf, mfn_save, PAGE_KERNEL); +} + +/* + * This function takes a contiguous pfn range that needs to be identity mapped + * and: + * + * 1) Finds a new range of pfns to use to remap based on E820 and remap_pfn. + * 2) Calls the do_ function to actually do the mapping/remapping work. + * + * The goal is to not allocate additional memory but to remap the existing + * pages. In the case of an error the underlying memory is simply released back + * to Xen and not remapped. + */ +static unsigned long __init xen_set_identity_and_remap_chunk( + const struct e820entry *list, size_t map_size, unsigned long start_pfn, + unsigned long end_pfn, unsigned long nr_pages, unsigned long remap_pfn, + unsigned long *released, unsigned long *remapped) +{ + unsigned long pfn; + unsigned long i = 0; + unsigned long n = end_pfn - start_pfn; + + while (i < n) { + unsigned long cur_pfn = start_pfn + i; + unsigned long left = n - i; + unsigned long size = left; + unsigned long remap_range_size; + + /* Do not remap pages beyond the current allocation */ + if (cur_pfn >= nr_pages) { + /* Identity map remaining pages */ + set_phys_range_identity(cur_pfn, cur_pfn + size); + break; + } + if (cur_pfn + size > nr_pages) + size = nr_pages - cur_pfn; + + remap_range_size = xen_find_pfn_range(list, map_size, + &remap_pfn); + if (!remap_range_size) { + pr_warning("Unable to find available pfn range, not remapping identity pages\n"); + xen_set_identity_and_release_chunk(cur_pfn, + cur_pfn + left, nr_pages, released); + break; + } + /* Adjust size to fit in current e820 RAM region */ + if (size > remap_range_size) + size = remap_range_size; + + xen_do_set_identity_and_remap_chunk(cur_pfn, size, remap_pfn); + + /* Update variables to reflect new mappings. */ + i += size; + remap_pfn += size; + *remapped += size; + } + + /* + * If the PFNs are currently mapped, the VA mapping also needs + * to be updated to be 1:1. + */ + for (pfn = start_pfn; pfn <= max_pfn_mapped && pfn < end_pfn; pfn++) + (void)HYPERVISOR_update_va_mapping( + (unsigned long)__va(pfn << PAGE_SHIFT), + mfn_pte(pfn, PAGE_KERNEL_IO), 0); + + return remap_pfn; +} + +static void __init xen_set_identity_and_remap( + const struct e820entry *list, size_t map_size, unsigned long nr_pages, + unsigned long *released, unsigned long *remapped) +{ + phys_addr_t start = 0; + unsigned long last_pfn = nr_pages; + const struct e820entry *entry; + unsigned long num_released = 0; + unsigned long num_remapped = 0; + int i; + + /* + * Combine non-RAM regions and gaps until a RAM region (or the + * end of the map) is reached, then set the 1:1 map and + * remap the memory in those non-RAM regions. + * + * 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, entry = list; i < map_size; i++, entry++) { + phys_addr_t end = entry->addr + entry->size; + if (entry->type == E820_RAM || i == map_size - 1) { + unsigned long start_pfn = PFN_DOWN(start); + unsigned long end_pfn = PFN_UP(end); + + if (entry->type == E820_RAM) + end_pfn = PFN_UP(entry->addr); + + if (start_pfn < end_pfn) + last_pfn = xen_set_identity_and_remap_chunk( + list, map_size, start_pfn, + end_pfn, nr_pages, last_pfn, + &num_released, &num_remapped); + start = end; + } + } + + *released = num_released; + *remapped = num_remapped; + + pr_info("Released %ld page(s)\n", num_released); +} + +/* + * 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 independant from the order. + */ +void __init xen_remap_memory(void) +{ + unsigned long buf = (unsigned long)&xen_remap_buf; + unsigned long mfn_save, mfn, 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++) { + mfn = xen_remap_buf.mfns[i]; + xen_update_mem_tables(pfn, mfn); + 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_PHYS(pfn_s), PFN_PHYS(len)); + pfn_s = xen_remap_buf.target_pfn; + len = xen_remap_buf.size; + } + + mfn = xen_remap_mfn; + xen_remap_mfn = xen_remap_buf.next_area_mfn; + } + + if (pfn_s != ~0UL && len) + xen_del_extra_mem(PFN_PHYS(pfn_s), PFN_PHYS(len)); + + set_pte_mfn(buf, mfn_save, PAGE_KERNEL); + + pr_info("Remapped %ld page(s)\n", remapped); +} + +static unsigned long __init xen_get_max_pages(void) +{ + unsigned long max_pages = MAX_DOMAIN_PAGES; + domid_t domid = DOMID_SELF; + int ret; + + /* + * 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, MAX_DOMAIN_PAGES); +} + +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_RAM) { + start = PAGE_ALIGN(start); + end &= ~((phys_addr_t)PAGE_SIZE - 1); + } + + e820_add_region(start, end - start, type); +} + +static void __init xen_ignore_unusable(struct e820entry *list, size_t map_size) +{ + struct e820entry *entry; + unsigned int i; + + for (i = 0, entry = list; i < map_size; i++, entry++) { + if (entry->type == E820_UNUSABLE) + entry->type = E820_RAM; + } +} + +/** + * machine_specific_memory_setup - Hook for machine specific memory setup. + **/ +char * __init xen_memory_setup(void) +{ + static struct e820entry map[E820MAX] __initdata; + + unsigned long max_pfn = xen_start_info->nr_pages; + phys_addr_t mem_end; + int rc; + struct xen_memory_map memmap; + unsigned long max_pages; + unsigned long extra_pages = 0; + unsigned long remapped_pages; + int i; + int op; + + max_pfn = min(MAX_DOMAIN_PAGES, max_pfn); + mem_end = PFN_PHYS(max_pfn); + + memmap.nr_entries = E820MAX; + set_xen_guest_handle(memmap.buffer, map); + + 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; + map[0].addr = 0ULL; + map[0].size = mem_end; + /* 8MB slack (to balance backend allocations). */ + map[0].size += 8ULL << 20; + map[0].type = E820_RAM; + rc = 0; + } + BUG_ON(rc); + BUG_ON(memmap.nr_entries == 0); + + /* + * 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(map, memmap.nr_entries); + + /* Make sure the Xen-supplied memory map is well-ordered. */ + sanitize_e820_map(map, memmap.nr_entries, &memmap.nr_entries); + + max_pages = xen_get_max_pages(); + if (max_pages > max_pfn) + extra_pages += max_pages - max_pfn; + + /* + * Set identity map on non-RAM pages and prepare remapping the + * underlying RAM. + */ + xen_set_identity_and_remap(map, memmap.nr_entries, max_pfn, + &xen_released_pages, &remapped_pages); + + extra_pages += xen_released_pages; + extra_pages += remapped_pages; + + /* + * 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. + * + * 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 = min(EXTRA_MEM_RATIO * min(max_pfn, PFN_DOWN(MAXMEM)), + extra_pages); + i = 0; + while (i < memmap.nr_entries) { + phys_addr_t addr = map[i].addr; + phys_addr_t size = map[i].size; + u32 type = map[i].type; + + if (type == E820_RAM) { + if (addr < mem_end) { + size = min(size, mem_end - addr); + } else if (extra_pages) { + size = min(size, PFN_PHYS(extra_pages)); + extra_pages -= PFN_DOWN(size); + xen_add_extra_mem(addr, size); + xen_max_p2m_pfn = PFN_DOWN(addr + size); + } else + type = E820_UNUSABLE; + } + + xen_align_and_add_e820_region(addr, size, type); + + map[i].addr += size; + map[i].size -= size; + if (map[i].size == 0) + i++; + } + + /* + * Set the rest as identity mapped, in case PCI BARs are + * located here. + * + * PFNs above MAX_P2M_PFN are considered identity mapped as + * well. + */ + set_phys_range_identity(map[i-1].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_add_region(ISA_START_ADDRESS, ISA_END_ADDRESS - ISA_START_ADDRESS, + E820_RESERVED); + + /* + * Reserve Xen bits: + * - mfn_list + * - xen_start_info + * See comment above "struct start_info" in <xen/interface/xen.h> + * We tried to make the the memblock_reserve more selective so + * that it would be clear what region is reserved. Sadly we ran + * in the problem wherein on a 64-bit hypervisor with a 32-bit + * initial domain, the pt_base has the cr3 value which is not + * neccessarily where the pagetable starts! As Jan put it: " + * Actually, the adjustment turns out to be correct: The page + * tables for a 32-on-64 dom0 get allocated in the order "first L1", + * "first L2", "first L3", so the offset to the page table base is + * indeed 2. When reading xen/include/public/xen.h's comment + * very strictly, this is not a violation (since there nothing is said + * that the first thing in the page table space is pointed to by + * pt_base; I admit that this seems to be implied though, namely + * do I think that it is implied that the page table space is the + * range [pt_base, pt_base + nt_pt_frames), whereas that + * range here indeed is [pt_base - 2, pt_base - 2 + nt_pt_frames), + * which - without a priori knowledge - the kernel would have + * difficulty to figure out)." - so lets just fall back to the + * easy way and reserve the whole region. + */ + memblock_reserve(__pa(xen_start_info->mfn_list), + xen_start_info->pt_base - xen_start_info->mfn_list); + + sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map); + + return "Xen"; +} + +/* + * Machine specific memory setup for auto-translated guests. + */ +char * __init xen_auto_xlated_memory_setup(void) +{ + static struct e820entry map[E820MAX] __initdata; + + struct xen_memory_map memmap; + int i; + int rc; + + memmap.nr_entries = E820MAX; + set_xen_guest_handle(memmap.buffer, map); + + rc = HYPERVISOR_memory_op(XENMEM_memory_map, &memmap); + if (rc < 0) + panic("No memory map (%d)\n", rc); + + sanitize_e820_map(map, ARRAY_SIZE(map), &memmap.nr_entries); + + for (i = 0; i < memmap.nr_entries; i++) + e820_add_region(map[i].addr, map[i].size, map[i].type); + + memblock_reserve(__pa(xen_start_info->mfn_list), + xen_start_info->pt_base - xen_start_info->mfn_list); + + 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 + /* + * This could be called before selected_vdso32 is initialized, so + * just fiddle with both possible images. vdso_image_32_syscall + * can't be selected, since it only exists on 64-bit systems. + */ + u32 *mask; + mask = vdso_image_32_int80.data + + vdso_image_32_int80.sym_VDSO32_NOTE_MASK; + *mask |= 1 << VDSO_NOTE_NONEGSEG_BIT; + mask = vdso_image_32_sysenter.data + + vdso_image_32_sysenter.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 */ +} + +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_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(); + if (!xen_feature(XENFEAT_auto_translated_physmap)) + 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 +} |