Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Xen leaves the responsibility for maintaining p2m mappings to the |
| 3 | * guests themselves, but it must also access and update the p2m array |
| 4 | * during suspend/resume when all the pages are reallocated. |
| 5 | * |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 6 | * The logical flat p2m table is mapped to a linear kernel memory area. |
| 7 | * For accesses by Xen a three-level tree linked via mfns only is set up to |
| 8 | * allow the address space to be sparse. |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 9 | * |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 10 | * Xen |
| 11 | * | |
| 12 | * p2m_top_mfn |
| 13 | * / \ |
| 14 | * p2m_mid_mfn p2m_mid_mfn |
| 15 | * / / |
| 16 | * p2m p2m p2m ... |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 17 | * |
| 18 | * The p2m_mid_mfn pages are mapped by p2m_top_mfn_p. |
| 19 | * |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 20 | * The p2m_top_mfn level is limited to 1 page, so the maximum representable |
| 21 | * pseudo-physical address space is: |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 22 | * P2M_TOP_PER_PAGE * P2M_MID_PER_PAGE * P2M_PER_PAGE pages |
| 23 | * |
| 24 | * P2M_PER_PAGE depends on the architecture, as a mfn is always |
| 25 | * unsigned long (8 bytes on 64-bit, 4 bytes on 32), leading to |
Konrad Rzeszutek Wilk | a3118be | 2012-06-28 22:12:36 -0400 | [diff] [blame] | 26 | * 512 and 1024 entries respectively. |
Konrad Rzeszutek Wilk | f4cec35 | 2011-01-18 20:15:21 -0500 | [diff] [blame] | 27 | * |
| 28 | * In short, these structures contain the Machine Frame Number (MFN) of the PFN. |
| 29 | * |
| 30 | * However not all entries are filled with MFNs. Specifically for all other |
| 31 | * leaf entries, or for the top root, or middle one, for which there is a void |
| 32 | * entry, we assume it is "missing". So (for example) |
| 33 | * pfn_to_mfn(0x90909090)=INVALID_P2M_ENTRY. |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 34 | * We have a dedicated page p2m_missing with all entries being |
| 35 | * INVALID_P2M_ENTRY. This page may be referenced multiple times in the p2m |
| 36 | * list/tree in case there are multiple areas with P2M_PER_PAGE invalid pfns. |
Konrad Rzeszutek Wilk | f4cec35 | 2011-01-18 20:15:21 -0500 | [diff] [blame] | 37 | * |
| 38 | * We also have the possibility of setting 1-1 mappings on certain regions, so |
| 39 | * that: |
| 40 | * pfn_to_mfn(0xc0000)=0xc0000 |
| 41 | * |
| 42 | * The benefit of this is, that we can assume for non-RAM regions (think |
David Vrabel | 3cb83e4 | 2014-01-07 11:44:32 +0000 | [diff] [blame] | 43 | * PCI BARs, or ACPI spaces), we can create mappings easily because we |
Konrad Rzeszutek Wilk | f4cec35 | 2011-01-18 20:15:21 -0500 | [diff] [blame] | 44 | * get the PFN value to match the MFN. |
| 45 | * |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 46 | * For this to work efficiently we have one new page p2m_identity. All entries |
| 47 | * in p2m_identity are set to INVALID_P2M_ENTRY type (Xen toolstack only |
| 48 | * recognizes that and MFNs, no other fancy value). |
Konrad Rzeszutek Wilk | f4cec35 | 2011-01-18 20:15:21 -0500 | [diff] [blame] | 49 | * |
| 50 | * On lookup we spot that the entry points to p2m_identity and return the |
| 51 | * identity value instead of dereferencing and returning INVALID_P2M_ENTRY. |
| 52 | * If the entry points to an allocated page, we just proceed as before and |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 53 | * return the PFN. If the PFN has IDENTITY_FRAME_BIT set we unmask that in |
Konrad Rzeszutek Wilk | f4cec35 | 2011-01-18 20:15:21 -0500 | [diff] [blame] | 54 | * appropriate functions (pfn_to_mfn). |
| 55 | * |
| 56 | * The reason for having the IDENTITY_FRAME_BIT instead of just returning the |
| 57 | * PFN is that we could find ourselves where pfn_to_mfn(pfn)==pfn for a |
| 58 | * non-identity pfn. To protect ourselves against we elect to set (and get) the |
| 59 | * IDENTITY_FRAME_BIT on all identity mapped PFNs. |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 60 | */ |
| 61 | |
| 62 | #include <linux/init.h> |
| 63 | #include <linux/module.h> |
Jeremy Fitzhardinge | 448f2831 | 2010-12-15 13:19:33 +0000 | [diff] [blame] | 64 | #include <linux/list.h> |
| 65 | #include <linux/hash.h> |
Jeremy Fitzhardinge | 87f1d40 | 2010-12-13 14:42:30 +0000 | [diff] [blame] | 66 | #include <linux/sched.h> |
Konrad Rzeszutek Wilk | 2222e71 | 2010-12-22 08:57:30 -0500 | [diff] [blame] | 67 | #include <linux/seq_file.h> |
Juergen Gross | 2c18568 | 2014-10-14 13:33:46 +0200 | [diff] [blame] | 68 | #include <linux/bootmem.h> |
Juergen Gross | 7108c9c | 2014-11-28 11:53:52 +0100 | [diff] [blame] | 69 | #include <linux/slab.h> |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 70 | |
| 71 | #include <asm/cache.h> |
| 72 | #include <asm/setup.h> |
Juergen Gross | 2e91717 | 2014-11-28 11:53:59 +0100 | [diff] [blame] | 73 | #include <asm/uaccess.h> |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 74 | |
| 75 | #include <asm/xen/page.h> |
| 76 | #include <asm/xen/hypercall.h> |
| 77 | #include <asm/xen/hypervisor.h> |
Stefano Stabellini | ee07264 | 2013-07-23 17:23:54 +0000 | [diff] [blame] | 78 | #include <xen/balloon.h> |
Stefano Stabellini | 0930bba | 2011-09-29 11:57:56 +0100 | [diff] [blame] | 79 | #include <xen/grant_table.h> |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 80 | |
Matt Rushton | 4fbb67e3 | 2014-08-11 11:57:57 -0700 | [diff] [blame] | 81 | #include "p2m.h" |
Stefano Stabellini | 0930bba | 2011-09-29 11:57:56 +0100 | [diff] [blame] | 82 | #include "multicalls.h" |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 83 | #include "xen-ops.h" |
| 84 | |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 85 | #define PMDS_PER_MID_PAGE (P2M_MID_PER_PAGE / PTRS_PER_PTE) |
| 86 | |
Juergen Gross | 5b8e7d8 | 2014-11-28 11:53:55 +0100 | [diff] [blame] | 87 | unsigned long *xen_p2m_addr __read_mostly; |
| 88 | EXPORT_SYMBOL_GPL(xen_p2m_addr); |
| 89 | unsigned long xen_p2m_size __read_mostly; |
| 90 | EXPORT_SYMBOL_GPL(xen_p2m_size); |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 91 | unsigned long xen_max_p2m_pfn __read_mostly; |
Juergen Gross | 5b8e7d8 | 2014-11-28 11:53:55 +0100 | [diff] [blame] | 92 | EXPORT_SYMBOL_GPL(xen_max_p2m_pfn); |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 93 | |
Juergen Gross | 633d6f1 | 2015-03-20 13:55:38 +0100 | [diff] [blame] | 94 | #ifdef CONFIG_XEN_BALLOON_MEMORY_HOTPLUG_LIMIT |
| 95 | #define P2M_LIMIT CONFIG_XEN_BALLOON_MEMORY_HOTPLUG_LIMIT |
| 96 | #else |
| 97 | #define P2M_LIMIT 0 |
| 98 | #endif |
| 99 | |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 100 | static DEFINE_SPINLOCK(p2m_update_lock); |
| 101 | |
Juergen Gross | 2c18568 | 2014-10-14 13:33:46 +0200 | [diff] [blame] | 102 | static unsigned long *p2m_mid_missing_mfn; |
| 103 | static unsigned long *p2m_top_mfn; |
| 104 | static unsigned long **p2m_top_mfn_p; |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 105 | static unsigned long *p2m_missing; |
| 106 | static unsigned long *p2m_identity; |
| 107 | static pte_t *p2m_missing_pte; |
| 108 | static pte_t *p2m_identity_pte; |
Juergen Gross | 7108c9c | 2014-11-28 11:53:52 +0100 | [diff] [blame] | 109 | |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 110 | static inline unsigned p2m_top_index(unsigned long pfn) |
| 111 | { |
| 112 | BUG_ON(pfn >= MAX_P2M_PFN); |
| 113 | return pfn / (P2M_MID_PER_PAGE * P2M_PER_PAGE); |
| 114 | } |
| 115 | |
| 116 | static inline unsigned p2m_mid_index(unsigned long pfn) |
| 117 | { |
| 118 | return (pfn / P2M_PER_PAGE) % P2M_MID_PER_PAGE; |
| 119 | } |
| 120 | |
| 121 | static inline unsigned p2m_index(unsigned long pfn) |
| 122 | { |
| 123 | return pfn % P2M_PER_PAGE; |
| 124 | } |
| 125 | |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 126 | static void p2m_top_mfn_init(unsigned long *top) |
| 127 | { |
| 128 | unsigned i; |
| 129 | |
| 130 | for (i = 0; i < P2M_TOP_PER_PAGE; i++) |
| 131 | top[i] = virt_to_mfn(p2m_mid_missing_mfn); |
| 132 | } |
| 133 | |
| 134 | static void p2m_top_mfn_p_init(unsigned long **top) |
| 135 | { |
| 136 | unsigned i; |
| 137 | |
| 138 | for (i = 0; i < P2M_TOP_PER_PAGE; i++) |
| 139 | top[i] = p2m_mid_missing_mfn; |
| 140 | } |
| 141 | |
David Vrabel | 3cb83e4 | 2014-01-07 11:44:32 +0000 | [diff] [blame] | 142 | static void p2m_mid_mfn_init(unsigned long *mid, unsigned long *leaf) |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 143 | { |
| 144 | unsigned i; |
| 145 | |
| 146 | for (i = 0; i < P2M_MID_PER_PAGE; i++) |
David Vrabel | 3cb83e4 | 2014-01-07 11:44:32 +0000 | [diff] [blame] | 147 | mid[i] = virt_to_mfn(leaf); |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 148 | } |
| 149 | |
| 150 | static void p2m_init(unsigned long *p2m) |
| 151 | { |
| 152 | unsigned i; |
| 153 | |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 154 | for (i = 0; i < P2M_PER_PAGE; i++) |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 155 | p2m[i] = INVALID_P2M_ENTRY; |
| 156 | } |
| 157 | |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 158 | static void p2m_init_identity(unsigned long *p2m, unsigned long pfn) |
| 159 | { |
| 160 | unsigned i; |
| 161 | |
| 162 | for (i = 0; i < P2M_PER_PAGE; i++) |
| 163 | p2m[i] = IDENTITY_FRAME(pfn + i); |
| 164 | } |
| 165 | |
Juergen Gross | 7108c9c | 2014-11-28 11:53:52 +0100 | [diff] [blame] | 166 | static void * __ref alloc_p2m_page(void) |
| 167 | { |
Juergen Gross | 7108c9c | 2014-11-28 11:53:52 +0100 | [diff] [blame] | 168 | if (unlikely(!slab_is_available())) |
| 169 | return alloc_bootmem_align(PAGE_SIZE, PAGE_SIZE); |
| 170 | |
| 171 | return (void *)__get_free_page(GFP_KERNEL | __GFP_REPEAT); |
| 172 | } |
| 173 | |
Boris Ostrovsky | 701a261 | 2015-01-07 09:08:54 -0500 | [diff] [blame] | 174 | static void __ref free_p2m_page(void *p) |
Juergen Gross | 7108c9c | 2014-11-28 11:53:52 +0100 | [diff] [blame] | 175 | { |
Boris Ostrovsky | 701a261 | 2015-01-07 09:08:54 -0500 | [diff] [blame] | 176 | if (unlikely(!slab_is_available())) { |
| 177 | free_bootmem((unsigned long)p, PAGE_SIZE); |
| 178 | return; |
| 179 | } |
| 180 | |
Juergen Gross | 7108c9c | 2014-11-28 11:53:52 +0100 | [diff] [blame] | 181 | free_page((unsigned long)p); |
| 182 | } |
| 183 | |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 184 | /* |
| 185 | * Build the parallel p2m_top_mfn and p2m_mid_mfn structures |
| 186 | * |
| 187 | * This is called both at boot time, and after resuming from suspend: |
Juergen Gross | 2c18568 | 2014-10-14 13:33:46 +0200 | [diff] [blame] | 188 | * - At boot time we're called rather early, and must use alloc_bootmem*() |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 189 | * to allocate memory. |
| 190 | * |
| 191 | * - After resume we're called from within stop_machine, but the mfn |
Juergen Gross | 2c18568 | 2014-10-14 13:33:46 +0200 | [diff] [blame] | 192 | * tree should already be completely allocated. |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 193 | */ |
Ian Campbell | 44b46c3 | 2011-02-11 16:37:41 +0000 | [diff] [blame] | 194 | void __ref xen_build_mfn_list_list(void) |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 195 | { |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 196 | unsigned long pfn, mfn; |
| 197 | pte_t *ptep; |
| 198 | unsigned int level, topidx, mididx; |
| 199 | unsigned long *mid_mfn_p; |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 200 | |
Konrad Rzeszutek Wilk | 696fd7c | 2013-12-15 12:37:46 -0500 | [diff] [blame] | 201 | if (xen_feature(XENFEAT_auto_translated_physmap)) |
| 202 | return; |
| 203 | |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 204 | /* Pre-initialize p2m_top_mfn to be completely missing */ |
| 205 | if (p2m_top_mfn == NULL) { |
Juergen Gross | 7108c9c | 2014-11-28 11:53:52 +0100 | [diff] [blame] | 206 | p2m_mid_missing_mfn = alloc_p2m_page(); |
David Vrabel | 3cb83e4 | 2014-01-07 11:44:32 +0000 | [diff] [blame] | 207 | p2m_mid_mfn_init(p2m_mid_missing_mfn, p2m_missing); |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 208 | |
Juergen Gross | 7108c9c | 2014-11-28 11:53:52 +0100 | [diff] [blame] | 209 | p2m_top_mfn_p = alloc_p2m_page(); |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 210 | p2m_top_mfn_p_init(p2m_top_mfn_p); |
| 211 | |
Juergen Gross | 7108c9c | 2014-11-28 11:53:52 +0100 | [diff] [blame] | 212 | p2m_top_mfn = alloc_p2m_page(); |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 213 | p2m_top_mfn_init(p2m_top_mfn); |
| 214 | } else { |
| 215 | /* Reinitialise, mfn's all change after migration */ |
David Vrabel | 3cb83e4 | 2014-01-07 11:44:32 +0000 | [diff] [blame] | 216 | p2m_mid_mfn_init(p2m_mid_missing_mfn, p2m_missing); |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 217 | } |
| 218 | |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 219 | for (pfn = 0; pfn < xen_max_p2m_pfn && pfn < MAX_P2M_PFN; |
| 220 | pfn += P2M_PER_PAGE) { |
| 221 | topidx = p2m_top_index(pfn); |
| 222 | mididx = p2m_mid_index(pfn); |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 223 | |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 224 | mid_mfn_p = p2m_top_mfn_p[topidx]; |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 225 | ptep = lookup_address((unsigned long)(xen_p2m_addr + pfn), |
| 226 | &level); |
| 227 | BUG_ON(!ptep || level != PG_LEVEL_4K); |
| 228 | mfn = pte_mfn(*ptep); |
| 229 | ptep = (pte_t *)((unsigned long)ptep & ~(PAGE_SIZE - 1)); |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 230 | |
| 231 | /* Don't bother allocating any mfn mid levels if |
| 232 | * they're just missing, just update the stored mfn, |
| 233 | * since all could have changed over a migrate. |
| 234 | */ |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 235 | if (ptep == p2m_missing_pte || ptep == p2m_identity_pte) { |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 236 | BUG_ON(mididx); |
| 237 | BUG_ON(mid_mfn_p != p2m_mid_missing_mfn); |
| 238 | p2m_top_mfn[topidx] = virt_to_mfn(p2m_mid_missing_mfn); |
| 239 | pfn += (P2M_MID_PER_PAGE - 1) * P2M_PER_PAGE; |
| 240 | continue; |
| 241 | } |
| 242 | |
| 243 | if (mid_mfn_p == p2m_mid_missing_mfn) { |
Juergen Gross | 7108c9c | 2014-11-28 11:53:52 +0100 | [diff] [blame] | 244 | mid_mfn_p = alloc_p2m_page(); |
David Vrabel | 3cb83e4 | 2014-01-07 11:44:32 +0000 | [diff] [blame] | 245 | p2m_mid_mfn_init(mid_mfn_p, p2m_missing); |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 246 | |
| 247 | p2m_top_mfn_p[topidx] = mid_mfn_p; |
| 248 | } |
| 249 | |
| 250 | p2m_top_mfn[topidx] = virt_to_mfn(mid_mfn_p); |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 251 | mid_mfn_p[mididx] = mfn; |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 252 | } |
| 253 | } |
| 254 | |
| 255 | void xen_setup_mfn_list_list(void) |
| 256 | { |
Mukesh Rathor | 4dd322b | 2013-12-31 14:02:44 -0500 | [diff] [blame] | 257 | if (xen_feature(XENFEAT_auto_translated_physmap)) |
| 258 | return; |
| 259 | |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 260 | BUG_ON(HYPERVISOR_shared_info == &xen_dummy_shared_info); |
| 261 | |
| 262 | HYPERVISOR_shared_info->arch.pfn_to_mfn_frame_list_list = |
| 263 | virt_to_mfn(p2m_top_mfn); |
| 264 | HYPERVISOR_shared_info->arch.max_pfn = xen_max_p2m_pfn; |
| 265 | } |
| 266 | |
| 267 | /* Set up p2m_top to point to the domain-builder provided p2m pages */ |
| 268 | void __init xen_build_dynamic_phys_to_machine(void) |
| 269 | { |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 270 | unsigned long pfn; |
| 271 | |
Konrad Rzeszutek Wilk | 696fd7c | 2013-12-15 12:37:46 -0500 | [diff] [blame] | 272 | if (xen_feature(XENFEAT_auto_translated_physmap)) |
| 273 | return; |
| 274 | |
Juergen Gross | 5b8e7d8 | 2014-11-28 11:53:55 +0100 | [diff] [blame] | 275 | xen_p2m_addr = (unsigned long *)xen_start_info->mfn_list; |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 276 | xen_p2m_size = ALIGN(xen_start_info->nr_pages, P2M_PER_PAGE); |
| 277 | |
| 278 | for (pfn = xen_start_info->nr_pages; pfn < xen_p2m_size; pfn++) |
| 279 | xen_p2m_addr[pfn] = INVALID_P2M_ENTRY; |
| 280 | |
| 281 | xen_max_p2m_pfn = xen_p2m_size; |
| 282 | } |
| 283 | |
| 284 | #define P2M_TYPE_IDENTITY 0 |
| 285 | #define P2M_TYPE_MISSING 1 |
| 286 | #define P2M_TYPE_PFN 2 |
| 287 | #define P2M_TYPE_UNKNOWN 3 |
| 288 | |
| 289 | static int xen_p2m_elem_type(unsigned long pfn) |
| 290 | { |
| 291 | unsigned long mfn; |
| 292 | |
| 293 | if (pfn >= xen_p2m_size) |
| 294 | return P2M_TYPE_IDENTITY; |
| 295 | |
| 296 | mfn = xen_p2m_addr[pfn]; |
| 297 | |
| 298 | if (mfn == INVALID_P2M_ENTRY) |
| 299 | return P2M_TYPE_MISSING; |
| 300 | |
| 301 | if (mfn & IDENTITY_FRAME_BIT) |
| 302 | return P2M_TYPE_IDENTITY; |
| 303 | |
| 304 | return P2M_TYPE_PFN; |
| 305 | } |
| 306 | |
| 307 | static void __init xen_rebuild_p2m_list(unsigned long *p2m) |
| 308 | { |
| 309 | unsigned int i, chunk; |
| 310 | unsigned long pfn; |
| 311 | unsigned long *mfns; |
| 312 | pte_t *ptep; |
| 313 | pmd_t *pmdp; |
| 314 | int type; |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 315 | |
Juergen Gross | 7108c9c | 2014-11-28 11:53:52 +0100 | [diff] [blame] | 316 | p2m_missing = alloc_p2m_page(); |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 317 | p2m_init(p2m_missing); |
Juergen Gross | 7108c9c | 2014-11-28 11:53:52 +0100 | [diff] [blame] | 318 | p2m_identity = alloc_p2m_page(); |
David Vrabel | 3cb83e4 | 2014-01-07 11:44:32 +0000 | [diff] [blame] | 319 | p2m_init(p2m_identity); |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 320 | |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 321 | p2m_missing_pte = alloc_p2m_page(); |
| 322 | paravirt_alloc_pte(&init_mm, __pa(p2m_missing_pte) >> PAGE_SHIFT); |
| 323 | p2m_identity_pte = alloc_p2m_page(); |
| 324 | paravirt_alloc_pte(&init_mm, __pa(p2m_identity_pte) >> PAGE_SHIFT); |
| 325 | for (i = 0; i < PTRS_PER_PTE; i++) { |
| 326 | set_pte(p2m_missing_pte + i, |
Juergen Gross | 2e91717 | 2014-11-28 11:53:59 +0100 | [diff] [blame] | 327 | pfn_pte(PFN_DOWN(__pa(p2m_missing)), PAGE_KERNEL_RO)); |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 328 | set_pte(p2m_identity_pte + i, |
Juergen Gross | 2e91717 | 2014-11-28 11:53:59 +0100 | [diff] [blame] | 329 | pfn_pte(PFN_DOWN(__pa(p2m_identity)), PAGE_KERNEL_RO)); |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 330 | } |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 331 | |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 332 | for (pfn = 0; pfn < xen_max_p2m_pfn; pfn += chunk) { |
Stefan Bader | 8e1b4cf | 2011-01-20 15:38:23 +0100 | [diff] [blame] | 333 | /* |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 334 | * Try to map missing/identity PMDs or p2m-pages if possible. |
| 335 | * We have to respect the structure of the mfn_list_list |
| 336 | * which will be built just afterwards. |
| 337 | * Chunk size to test is one p2m page if we are in the middle |
| 338 | * of a mfn_list_list mid page and the complete mid page area |
| 339 | * if we are at index 0 of the mid page. Please note that a |
| 340 | * mid page might cover more than one PMD, e.g. on 32 bit PAE |
| 341 | * kernels. |
Stefan Bader | 8e1b4cf | 2011-01-20 15:38:23 +0100 | [diff] [blame] | 342 | */ |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 343 | chunk = (pfn & (P2M_PER_PAGE * P2M_MID_PER_PAGE - 1)) ? |
| 344 | P2M_PER_PAGE : P2M_PER_PAGE * P2M_MID_PER_PAGE; |
Stefan Bader | 8e1b4cf | 2011-01-20 15:38:23 +0100 | [diff] [blame] | 345 | |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 346 | type = xen_p2m_elem_type(pfn); |
| 347 | i = 0; |
| 348 | if (type != P2M_TYPE_PFN) |
| 349 | for (i = 1; i < chunk; i++) |
| 350 | if (xen_p2m_elem_type(pfn + i) != type) |
| 351 | break; |
| 352 | if (i < chunk) |
| 353 | /* Reset to minimal chunk size. */ |
| 354 | chunk = P2M_PER_PAGE; |
| 355 | |
| 356 | if (type == P2M_TYPE_PFN || i < chunk) { |
| 357 | /* Use initial p2m page contents. */ |
Konrad Rzeszutek Wilk | 357a3cf | 2012-07-19 13:52:29 -0400 | [diff] [blame] | 358 | #ifdef CONFIG_X86_64 |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 359 | mfns = alloc_p2m_page(); |
| 360 | copy_page(mfns, xen_p2m_addr + pfn); |
Konrad Rzeszutek Wilk | 357a3cf | 2012-07-19 13:52:29 -0400 | [diff] [blame] | 361 | #else |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 362 | mfns = xen_p2m_addr + pfn; |
Konrad Rzeszutek Wilk | 357a3cf | 2012-07-19 13:52:29 -0400 | [diff] [blame] | 363 | #endif |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 364 | ptep = populate_extra_pte((unsigned long)(p2m + pfn)); |
| 365 | set_pte(ptep, |
| 366 | pfn_pte(PFN_DOWN(__pa(mfns)), PAGE_KERNEL)); |
| 367 | continue; |
| 368 | } |
| 369 | |
| 370 | if (chunk == P2M_PER_PAGE) { |
| 371 | /* Map complete missing or identity p2m-page. */ |
| 372 | mfns = (type == P2M_TYPE_MISSING) ? |
| 373 | p2m_missing : p2m_identity; |
| 374 | ptep = populate_extra_pte((unsigned long)(p2m + pfn)); |
| 375 | set_pte(ptep, |
Juergen Gross | 2e91717 | 2014-11-28 11:53:59 +0100 | [diff] [blame] | 376 | pfn_pte(PFN_DOWN(__pa(mfns)), PAGE_KERNEL_RO)); |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 377 | continue; |
| 378 | } |
| 379 | |
| 380 | /* Complete missing or identity PMD(s) can be mapped. */ |
| 381 | ptep = (type == P2M_TYPE_MISSING) ? |
| 382 | p2m_missing_pte : p2m_identity_pte; |
| 383 | for (i = 0; i < PMDS_PER_MID_PAGE; i++) { |
| 384 | pmdp = populate_extra_pmd( |
Juergen Gross | 82c92ed | 2015-01-12 06:05:07 +0100 | [diff] [blame] | 385 | (unsigned long)(p2m + pfn) + i * PMD_SIZE); |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 386 | set_pmd(pmdp, __pmd(__pa(ptep) | _KERNPG_TABLE)); |
| 387 | } |
| 388 | } |
| 389 | } |
| 390 | |
| 391 | void __init xen_vmalloc_p2m_tree(void) |
| 392 | { |
| 393 | static struct vm_struct vm; |
Juergen Gross | 633d6f1 | 2015-03-20 13:55:38 +0100 | [diff] [blame] | 394 | unsigned long p2m_limit; |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 395 | |
Juergen Gross | 633d6f1 | 2015-03-20 13:55:38 +0100 | [diff] [blame] | 396 | p2m_limit = (phys_addr_t)P2M_LIMIT * 1024 * 1024 * 1024 / PAGE_SIZE; |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 397 | vm.flags = VM_ALLOC; |
Juergen Gross | 633d6f1 | 2015-03-20 13:55:38 +0100 | [diff] [blame] | 398 | vm.size = ALIGN(sizeof(unsigned long) * max(xen_max_p2m_pfn, p2m_limit), |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 399 | PMD_SIZE * PMDS_PER_MID_PAGE); |
| 400 | vm_area_register_early(&vm, PMD_SIZE * PMDS_PER_MID_PAGE); |
| 401 | pr_notice("p2m virtual area at %p, size is %lx\n", vm.addr, vm.size); |
| 402 | |
| 403 | xen_max_p2m_pfn = vm.size / sizeof(unsigned long); |
| 404 | |
| 405 | xen_rebuild_p2m_list(vm.addr); |
| 406 | |
| 407 | xen_p2m_addr = vm.addr; |
| 408 | xen_p2m_size = xen_max_p2m_pfn; |
| 409 | |
| 410 | xen_inv_extra_mem(); |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 411 | } |
| 412 | |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 413 | unsigned long get_phys_to_machine(unsigned long pfn) |
| 414 | { |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 415 | pte_t *ptep; |
| 416 | unsigned int level; |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 417 | |
Juergen Gross | 5b8e7d8 | 2014-11-28 11:53:55 +0100 | [diff] [blame] | 418 | if (unlikely(pfn >= xen_p2m_size)) { |
| 419 | if (pfn < xen_max_p2m_pfn) |
| 420 | return xen_chk_extra_mem(pfn); |
| 421 | |
David Vrabel | 25b884a | 2014-01-03 15:46:10 +0000 | [diff] [blame] | 422 | return IDENTITY_FRAME(pfn); |
Juergen Gross | 5b8e7d8 | 2014-11-28 11:53:55 +0100 | [diff] [blame] | 423 | } |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 424 | |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 425 | ptep = lookup_address((unsigned long)(xen_p2m_addr + pfn), &level); |
| 426 | BUG_ON(!ptep || level != PG_LEVEL_4K); |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 427 | |
Konrad Rzeszutek Wilk | f4cec35 | 2011-01-18 20:15:21 -0500 | [diff] [blame] | 428 | /* |
| 429 | * The INVALID_P2M_ENTRY is filled in both p2m_*identity |
| 430 | * and in p2m_*missing, so returning the INVALID_P2M_ENTRY |
| 431 | * would be wrong. |
| 432 | */ |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 433 | if (pte_pfn(*ptep) == PFN_DOWN(__pa(p2m_identity))) |
Konrad Rzeszutek Wilk | f4cec35 | 2011-01-18 20:15:21 -0500 | [diff] [blame] | 434 | return IDENTITY_FRAME(pfn); |
| 435 | |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 436 | return xen_p2m_addr[pfn]; |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 437 | } |
| 438 | EXPORT_SYMBOL_GPL(get_phys_to_machine); |
| 439 | |
Konrad Rzeszutek Wilk | a3118be | 2012-06-28 22:12:36 -0400 | [diff] [blame] | 440 | /* |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 441 | * Allocate new pmd(s). It is checked whether the old pmd is still in place. |
| 442 | * If not, nothing is changed. This is okay as the only reason for allocating |
| 443 | * a new pmd is to replace p2m_missing_pte or p2m_identity_pte by a individual |
| 444 | * pmd. In case of PAE/x86-32 there are multiple pmds to allocate! |
| 445 | */ |
Juergen Gross | f241b0b | 2015-01-12 06:05:08 +0100 | [diff] [blame] | 446 | static pte_t *alloc_p2m_pmd(unsigned long addr, pte_t *pte_pg) |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 447 | { |
| 448 | pte_t *ptechk; |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 449 | pte_t *pte_newpg[PMDS_PER_MID_PAGE]; |
| 450 | pmd_t *pmdp; |
| 451 | unsigned int level; |
| 452 | unsigned long flags; |
| 453 | unsigned long vaddr; |
| 454 | int i; |
| 455 | |
| 456 | /* Do all allocations first to bail out in error case. */ |
| 457 | for (i = 0; i < PMDS_PER_MID_PAGE; i++) { |
| 458 | pte_newpg[i] = alloc_p2m_page(); |
| 459 | if (!pte_newpg[i]) { |
| 460 | for (i--; i >= 0; i--) |
| 461 | free_p2m_page(pte_newpg[i]); |
| 462 | |
| 463 | return NULL; |
| 464 | } |
| 465 | } |
| 466 | |
| 467 | vaddr = addr & ~(PMD_SIZE * PMDS_PER_MID_PAGE - 1); |
| 468 | |
| 469 | for (i = 0; i < PMDS_PER_MID_PAGE; i++) { |
| 470 | copy_page(pte_newpg[i], pte_pg); |
| 471 | paravirt_alloc_pte(&init_mm, __pa(pte_newpg[i]) >> PAGE_SHIFT); |
| 472 | |
| 473 | pmdp = lookup_pmd_address(vaddr); |
| 474 | BUG_ON(!pmdp); |
| 475 | |
| 476 | spin_lock_irqsave(&p2m_update_lock, flags); |
| 477 | |
| 478 | ptechk = lookup_address(vaddr, &level); |
| 479 | if (ptechk == pte_pg) { |
| 480 | set_pmd(pmdp, |
| 481 | __pmd(__pa(pte_newpg[i]) | _KERNPG_TABLE)); |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 482 | pte_newpg[i] = NULL; |
| 483 | } |
| 484 | |
| 485 | spin_unlock_irqrestore(&p2m_update_lock, flags); |
| 486 | |
| 487 | if (pte_newpg[i]) { |
| 488 | paravirt_release_pte(__pa(pte_newpg[i]) >> PAGE_SHIFT); |
| 489 | free_p2m_page(pte_newpg[i]); |
| 490 | } |
| 491 | |
| 492 | vaddr += PMD_SIZE; |
| 493 | } |
| 494 | |
Juergen Gross | f241b0b | 2015-01-12 06:05:08 +0100 | [diff] [blame] | 495 | return lookup_address(addr, &level); |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 496 | } |
| 497 | |
| 498 | /* |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 499 | * Fully allocate the p2m structure for a given pfn. We need to check |
| 500 | * that both the top and mid levels are allocated, and make sure the |
| 501 | * parallel mfn tree is kept in sync. We may race with other cpus, so |
| 502 | * the new pages are installed with cmpxchg; if we lose the race then |
| 503 | * simply free the page we allocated and use the one that's there. |
| 504 | */ |
| 505 | static bool alloc_p2m(unsigned long pfn) |
| 506 | { |
| 507 | unsigned topidx, mididx; |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 508 | unsigned long *top_mfn_p, *mid_mfn; |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 509 | pte_t *ptep, *pte_pg; |
| 510 | unsigned int level; |
| 511 | unsigned long flags; |
| 512 | unsigned long addr = (unsigned long)(xen_p2m_addr + pfn); |
| 513 | unsigned long p2m_pfn; |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 514 | |
| 515 | topidx = p2m_top_index(pfn); |
| 516 | mididx = p2m_mid_index(pfn); |
| 517 | |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 518 | ptep = lookup_address(addr, &level); |
| 519 | BUG_ON(!ptep || level != PG_LEVEL_4K); |
| 520 | pte_pg = (pte_t *)((unsigned long)ptep & ~(PAGE_SIZE - 1)); |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 521 | |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 522 | if (pte_pg == p2m_missing_pte || pte_pg == p2m_identity_pte) { |
| 523 | /* PMD level is missing, allocate a new one */ |
Juergen Gross | f241b0b | 2015-01-12 06:05:08 +0100 | [diff] [blame] | 524 | ptep = alloc_p2m_pmd(addr, pte_pg); |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 525 | if (!ptep) |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 526 | return false; |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 527 | } |
| 528 | |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 529 | if (p2m_top_mfn) { |
| 530 | top_mfn_p = &p2m_top_mfn[topidx]; |
| 531 | mid_mfn = ACCESS_ONCE(p2m_top_mfn_p[topidx]); |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 532 | |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 533 | BUG_ON(virt_to_mfn(mid_mfn) != *top_mfn_p); |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 534 | |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 535 | if (mid_mfn == p2m_mid_missing_mfn) { |
| 536 | /* Separately check the mid mfn level */ |
| 537 | unsigned long missing_mfn; |
| 538 | unsigned long mid_mfn_mfn; |
| 539 | unsigned long old_mfn; |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 540 | |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 541 | mid_mfn = alloc_p2m_page(); |
| 542 | if (!mid_mfn) |
| 543 | return false; |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 544 | |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 545 | p2m_mid_mfn_init(mid_mfn, p2m_missing); |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 546 | |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 547 | missing_mfn = virt_to_mfn(p2m_mid_missing_mfn); |
| 548 | mid_mfn_mfn = virt_to_mfn(mid_mfn); |
| 549 | old_mfn = cmpxchg(top_mfn_p, missing_mfn, mid_mfn_mfn); |
| 550 | if (old_mfn != missing_mfn) { |
| 551 | free_p2m_page(mid_mfn); |
| 552 | mid_mfn = mfn_to_virt(old_mfn); |
| 553 | } else { |
| 554 | p2m_top_mfn_p[topidx] = mid_mfn; |
| 555 | } |
Juergen Gross | 239af7c | 2014-10-14 11:00:18 +0200 | [diff] [blame] | 556 | } |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 557 | } else { |
| 558 | mid_mfn = NULL; |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 559 | } |
| 560 | |
Christian Borntraeger | 1760f1e | 2014-12-07 22:01:59 +0100 | [diff] [blame] | 561 | p2m_pfn = pte_pfn(READ_ONCE(*ptep)); |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 562 | if (p2m_pfn == PFN_DOWN(__pa(p2m_identity)) || |
| 563 | p2m_pfn == PFN_DOWN(__pa(p2m_missing))) { |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 564 | /* p2m leaf page is missing */ |
| 565 | unsigned long *p2m; |
| 566 | |
| 567 | p2m = alloc_p2m_page(); |
| 568 | if (!p2m) |
| 569 | return false; |
| 570 | |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 571 | if (p2m_pfn == PFN_DOWN(__pa(p2m_missing))) |
| 572 | p2m_init(p2m); |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 573 | else |
Juergen Gross | b8f05c8 | 2015-02-27 15:45:29 +0100 | [diff] [blame] | 574 | p2m_init_identity(p2m, pfn & ~(P2M_PER_PAGE - 1)); |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 575 | |
| 576 | spin_lock_irqsave(&p2m_update_lock, flags); |
| 577 | |
| 578 | if (pte_pfn(*ptep) == p2m_pfn) { |
| 579 | set_pte(ptep, |
| 580 | pfn_pte(PFN_DOWN(__pa(p2m)), PAGE_KERNEL)); |
| 581 | if (mid_mfn) |
| 582 | mid_mfn[mididx] = virt_to_mfn(p2m); |
| 583 | p2m = NULL; |
| 584 | } |
| 585 | |
| 586 | spin_unlock_irqrestore(&p2m_update_lock, flags); |
| 587 | |
| 588 | if (p2m) |
| 589 | free_p2m_page(p2m); |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 590 | } |
| 591 | |
| 592 | return true; |
| 593 | } |
| 594 | |
Randy Dunlap | b83c6e5 | 2011-03-24 13:34:32 -0700 | [diff] [blame] | 595 | unsigned long __init set_phys_range_identity(unsigned long pfn_s, |
Konrad Rzeszutek Wilk | f4cec35 | 2011-01-18 20:15:21 -0500 | [diff] [blame] | 596 | unsigned long pfn_e) |
| 597 | { |
| 598 | unsigned long pfn; |
| 599 | |
Juergen Gross | 5b8e7d8 | 2014-11-28 11:53:55 +0100 | [diff] [blame] | 600 | if (unlikely(pfn_s >= xen_p2m_size)) |
Konrad Rzeszutek Wilk | f4cec35 | 2011-01-18 20:15:21 -0500 | [diff] [blame] | 601 | return 0; |
| 602 | |
| 603 | if (unlikely(xen_feature(XENFEAT_auto_translated_physmap))) |
| 604 | return pfn_e - pfn_s; |
| 605 | |
| 606 | if (pfn_s > pfn_e) |
| 607 | return 0; |
| 608 | |
Juergen Gross | 5b8e7d8 | 2014-11-28 11:53:55 +0100 | [diff] [blame] | 609 | if (pfn_e > xen_p2m_size) |
| 610 | pfn_e = xen_p2m_size; |
David Vrabel | a9b5bff | 2014-01-06 11:55:13 +0000 | [diff] [blame] | 611 | |
Juergen Gross | 5b8e7d8 | 2014-11-28 11:53:55 +0100 | [diff] [blame] | 612 | for (pfn = pfn_s; pfn < pfn_e; pfn++) |
| 613 | xen_p2m_addr[pfn] = IDENTITY_FRAME(pfn); |
Konrad Rzeszutek Wilk | f4cec35 | 2011-01-18 20:15:21 -0500 | [diff] [blame] | 614 | |
| 615 | return pfn - pfn_s; |
| 616 | } |
| 617 | |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 618 | bool __set_phys_to_machine(unsigned long pfn, unsigned long mfn) |
| 619 | { |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 620 | pte_t *ptep; |
| 621 | unsigned int level; |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 622 | |
Stefano Stabellini | 2f558d4 | 2013-10-09 20:39:01 +0000 | [diff] [blame] | 623 | /* don't track P2M changes in autotranslate guests */ |
| 624 | if (unlikely(xen_feature(XENFEAT_auto_translated_physmap))) |
Konrad Rzeszutek Wilk | 6eaa412 | 2011-01-18 20:09:41 -0500 | [diff] [blame] | 625 | return true; |
Stefano Stabellini | 2f558d4 | 2013-10-09 20:39:01 +0000 | [diff] [blame] | 626 | |
Juergen Gross | 5b8e7d8 | 2014-11-28 11:53:55 +0100 | [diff] [blame] | 627 | if (unlikely(pfn >= xen_p2m_size)) { |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 628 | BUG_ON(mfn != INVALID_P2M_ENTRY); |
| 629 | return true; |
| 630 | } |
| 631 | |
Juergen Gross | 90fff3e | 2014-12-05 13:28:04 +0100 | [diff] [blame] | 632 | if (likely(!xen_safe_write_ulong(xen_p2m_addr + pfn, mfn))) |
Juergen Gross | 2e91717 | 2014-11-28 11:53:59 +0100 | [diff] [blame] | 633 | return true; |
| 634 | |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 635 | ptep = lookup_address((unsigned long)(xen_p2m_addr + pfn), &level); |
| 636 | BUG_ON(!ptep || level != PG_LEVEL_4K); |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 637 | |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 638 | if (pte_pfn(*ptep) == PFN_DOWN(__pa(p2m_missing))) |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 639 | return mfn == INVALID_P2M_ENTRY; |
| 640 | |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 641 | if (pte_pfn(*ptep) == PFN_DOWN(__pa(p2m_identity))) |
| 642 | return mfn == IDENTITY_FRAME(pfn); |
| 643 | |
Juergen Gross | 2e91717 | 2014-11-28 11:53:59 +0100 | [diff] [blame] | 644 | return false; |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 645 | } |
| 646 | |
| 647 | bool set_phys_to_machine(unsigned long pfn, unsigned long mfn) |
| 648 | { |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 649 | if (unlikely(!__set_phys_to_machine(pfn, mfn))) { |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 650 | if (!alloc_p2m(pfn)) |
| 651 | return false; |
| 652 | |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 653 | return __set_phys_to_machine(pfn, mfn); |
Jeremy Fitzhardinge | b5eafe9 | 2010-12-06 16:29:22 -0800 | [diff] [blame] | 654 | } |
| 655 | |
| 656 | return true; |
| 657 | } |
Jeremy Fitzhardinge | 448f2831 | 2010-12-15 13:19:33 +0000 | [diff] [blame] | 658 | |
Zoltan Kiss | 1429d46 | 2014-02-27 15:55:30 +0000 | [diff] [blame] | 659 | int set_foreign_p2m_mapping(struct gnttab_map_grant_ref *map_ops, |
| 660 | struct gnttab_map_grant_ref *kmap_ops, |
| 661 | struct page **pages, unsigned int count) |
| 662 | { |
| 663 | int i, ret = 0; |
Zoltan Kiss | 1429d46 | 2014-02-27 15:55:30 +0000 | [diff] [blame] | 664 | pte_t *pte; |
| 665 | |
| 666 | if (xen_feature(XENFEAT_auto_translated_physmap)) |
| 667 | return 0; |
| 668 | |
David Vrabel | 0bb599f | 2015-01-05 17:06:01 +0000 | [diff] [blame] | 669 | if (kmap_ops) { |
| 670 | ret = HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, |
| 671 | kmap_ops, count); |
| 672 | if (ret) |
| 673 | goto out; |
Zoltan Kiss | 1429d46 | 2014-02-27 15:55:30 +0000 | [diff] [blame] | 674 | } |
| 675 | |
| 676 | for (i = 0; i < count; i++) { |
| 677 | unsigned long mfn, pfn; |
| 678 | |
| 679 | /* Do not add to override if the map failed. */ |
| 680 | if (map_ops[i].status) |
| 681 | continue; |
| 682 | |
| 683 | if (map_ops[i].flags & GNTMAP_contains_pte) { |
Juergen Gross | 6f58d89 | 2014-11-28 11:53:50 +0100 | [diff] [blame] | 684 | pte = (pte_t *)(mfn_to_virt(PFN_DOWN(map_ops[i].host_addr)) + |
Zoltan Kiss | 1429d46 | 2014-02-27 15:55:30 +0000 | [diff] [blame] | 685 | (map_ops[i].host_addr & ~PAGE_MASK)); |
| 686 | mfn = pte_mfn(*pte); |
| 687 | } else { |
| 688 | mfn = PFN_DOWN(map_ops[i].dev_bus_addr); |
| 689 | } |
| 690 | pfn = page_to_pfn(pages[i]); |
| 691 | |
Jennifer Herbert | 0ae65f4 | 2014-12-24 14:03:16 +0000 | [diff] [blame] | 692 | WARN(pfn_to_mfn(pfn) != INVALID_P2M_ENTRY, "page must be ballooned"); |
| 693 | |
Zoltan Kiss | 1429d46 | 2014-02-27 15:55:30 +0000 | [diff] [blame] | 694 | if (unlikely(!set_phys_to_machine(pfn, FOREIGN_FRAME(mfn)))) { |
| 695 | ret = -ENOMEM; |
| 696 | goto out; |
| 697 | } |
Zoltan Kiss | 1429d46 | 2014-02-27 15:55:30 +0000 | [diff] [blame] | 698 | } |
| 699 | |
| 700 | out: |
Zoltan Kiss | 1429d46 | 2014-02-27 15:55:30 +0000 | [diff] [blame] | 701 | return ret; |
| 702 | } |
| 703 | EXPORT_SYMBOL_GPL(set_foreign_p2m_mapping); |
| 704 | |
Juergen Gross | 820c4db | 2014-11-28 11:53:51 +0100 | [diff] [blame] | 705 | int clear_foreign_p2m_mapping(struct gnttab_unmap_grant_ref *unmap_ops, |
David Vrabel | 853d028 | 2015-01-05 14:13:41 +0000 | [diff] [blame] | 706 | struct gnttab_unmap_grant_ref *kunmap_ops, |
Juergen Gross | 820c4db | 2014-11-28 11:53:51 +0100 | [diff] [blame] | 707 | struct page **pages, unsigned int count) |
Jeremy Fitzhardinge | 448f2831 | 2010-12-15 13:19:33 +0000 | [diff] [blame] | 708 | { |
Juergen Gross | 820c4db | 2014-11-28 11:53:51 +0100 | [diff] [blame] | 709 | int i, ret = 0; |
Jeremy Fitzhardinge | 448f2831 | 2010-12-15 13:19:33 +0000 | [diff] [blame] | 710 | |
Juergen Gross | 820c4db | 2014-11-28 11:53:51 +0100 | [diff] [blame] | 711 | if (xen_feature(XENFEAT_auto_translated_physmap)) |
| 712 | return 0; |
Jeremy Fitzhardinge | 448f2831 | 2010-12-15 13:19:33 +0000 | [diff] [blame] | 713 | |
Juergen Gross | 820c4db | 2014-11-28 11:53:51 +0100 | [diff] [blame] | 714 | for (i = 0; i < count; i++) { |
Juergen Gross | 0aad568 | 2014-11-28 11:53:57 +0100 | [diff] [blame] | 715 | unsigned long mfn = __pfn_to_mfn(page_to_pfn(pages[i])); |
Juergen Gross | 820c4db | 2014-11-28 11:53:51 +0100 | [diff] [blame] | 716 | unsigned long pfn = page_to_pfn(pages[i]); |
Jeremy Fitzhardinge | 448f2831 | 2010-12-15 13:19:33 +0000 | [diff] [blame] | 717 | |
Juergen Gross | 820c4db | 2014-11-28 11:53:51 +0100 | [diff] [blame] | 718 | if (mfn == INVALID_P2M_ENTRY || !(mfn & FOREIGN_FRAME_BIT)) { |
| 719 | ret = -EINVAL; |
| 720 | goto out; |
| 721 | } |
| 722 | |
Jennifer Herbert | 0ae65f4 | 2014-12-24 14:03:16 +0000 | [diff] [blame] | 723 | set_phys_to_machine(pfn, INVALID_P2M_ENTRY); |
Juergen Gross | 820c4db | 2014-11-28 11:53:51 +0100 | [diff] [blame] | 724 | } |
David Vrabel | 0bb599f | 2015-01-05 17:06:01 +0000 | [diff] [blame] | 725 | if (kunmap_ops) |
| 726 | ret = HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, |
| 727 | kunmap_ops, count); |
Juergen Gross | 820c4db | 2014-11-28 11:53:51 +0100 | [diff] [blame] | 728 | out: |
Jeremy Fitzhardinge | 448f2831 | 2010-12-15 13:19:33 +0000 | [diff] [blame] | 729 | return ret; |
| 730 | } |
Juergen Gross | 820c4db | 2014-11-28 11:53:51 +0100 | [diff] [blame] | 731 | EXPORT_SYMBOL_GPL(clear_foreign_p2m_mapping); |
Jeremy Fitzhardinge | 448f2831 | 2010-12-15 13:19:33 +0000 | [diff] [blame] | 732 | |
Konrad Rzeszutek Wilk | 2222e71 | 2010-12-22 08:57:30 -0500 | [diff] [blame] | 733 | #ifdef CONFIG_XEN_DEBUG_FS |
Konrad Rzeszutek Wilk | a867db1 | 2011-09-23 16:32:47 -0400 | [diff] [blame] | 734 | #include <linux/debugfs.h> |
| 735 | #include "debugfs.h" |
| 736 | static int p2m_dump_show(struct seq_file *m, void *v) |
Konrad Rzeszutek Wilk | 2222e71 | 2010-12-22 08:57:30 -0500 | [diff] [blame] | 737 | { |
Konrad Rzeszutek Wilk | a491dbe | 2011-10-03 12:35:26 -0400 | [diff] [blame] | 738 | static const char * const type_name[] = { |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 739 | [P2M_TYPE_IDENTITY] = "identity", |
| 740 | [P2M_TYPE_MISSING] = "missing", |
| 741 | [P2M_TYPE_PFN] = "pfn", |
| 742 | [P2M_TYPE_UNKNOWN] = "abnormal"}; |
| 743 | unsigned long pfn, first_pfn; |
| 744 | int type, prev_type; |
Konrad Rzeszutek Wilk | 2222e71 | 2010-12-22 08:57:30 -0500 | [diff] [blame] | 745 | |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 746 | prev_type = xen_p2m_elem_type(0); |
| 747 | first_pfn = 0; |
Konrad Rzeszutek Wilk | 2222e71 | 2010-12-22 08:57:30 -0500 | [diff] [blame] | 748 | |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 749 | for (pfn = 0; pfn < xen_p2m_size; pfn++) { |
| 750 | type = xen_p2m_elem_type(pfn); |
| 751 | if (type != prev_type) { |
| 752 | seq_printf(m, " [0x%lx->0x%lx] %s\n", first_pfn, pfn, |
| 753 | type_name[prev_type]); |
Konrad Rzeszutek Wilk | 2222e71 | 2010-12-22 08:57:30 -0500 | [diff] [blame] | 754 | prev_type = type; |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 755 | first_pfn = pfn; |
Konrad Rzeszutek Wilk | 2222e71 | 2010-12-22 08:57:30 -0500 | [diff] [blame] | 756 | } |
| 757 | } |
Juergen Gross | 054954e | 2014-11-28 11:53:58 +0100 | [diff] [blame] | 758 | seq_printf(m, " [0x%lx->0x%lx] %s\n", first_pfn, pfn, |
| 759 | type_name[prev_type]); |
Konrad Rzeszutek Wilk | 2222e71 | 2010-12-22 08:57:30 -0500 | [diff] [blame] | 760 | return 0; |
Konrad Rzeszutek Wilk | 2222e71 | 2010-12-22 08:57:30 -0500 | [diff] [blame] | 761 | } |
Konrad Rzeszutek Wilk | a867db1 | 2011-09-23 16:32:47 -0400 | [diff] [blame] | 762 | |
| 763 | static int p2m_dump_open(struct inode *inode, struct file *filp) |
| 764 | { |
| 765 | return single_open(filp, p2m_dump_show, NULL); |
| 766 | } |
| 767 | |
| 768 | static const struct file_operations p2m_dump_fops = { |
| 769 | .open = p2m_dump_open, |
| 770 | .read = seq_read, |
| 771 | .llseek = seq_lseek, |
| 772 | .release = single_release, |
| 773 | }; |
| 774 | |
| 775 | static struct dentry *d_mmu_debug; |
| 776 | |
| 777 | static int __init xen_p2m_debugfs(void) |
| 778 | { |
| 779 | struct dentry *d_xen = xen_init_debugfs(); |
| 780 | |
| 781 | if (d_xen == NULL) |
| 782 | return -ENOMEM; |
| 783 | |
| 784 | d_mmu_debug = debugfs_create_dir("mmu", d_xen); |
| 785 | |
| 786 | debugfs_create_file("p2m", 0600, d_mmu_debug, NULL, &p2m_dump_fops); |
| 787 | return 0; |
| 788 | } |
| 789 | fs_initcall(xen_p2m_debugfs); |
| 790 | #endif /* CONFIG_XEN_DEBUG_FS */ |