| 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
| 2 | #ifndef _ASM_X86_XEN_PAGE_H |
| 3 | #define _ASM_X86_XEN_PAGE_H |
| 4 | |
| 5 | #include <linux/kernel.h> |
| 6 | #include <linux/types.h> |
| 7 | #include <linux/spinlock.h> |
| 8 | #include <linux/pfn.h> |
| 9 | #include <linux/mm.h> |
| 10 | #include <linux/device.h> |
| 11 | |
| 12 | #include <asm/extable.h> |
| 13 | #include <asm/page.h> |
| 14 | |
| 15 | #include <xen/interface/xen.h> |
| 16 | #include <xen/interface/grant_table.h> |
| 17 | #include <xen/features.h> |
| 18 | |
| 19 | /* Xen machine address */ |
| 20 | typedef struct xmaddr { |
| 21 | phys_addr_t maddr; |
| 22 | } xmaddr_t; |
| 23 | |
| 24 | /* Xen pseudo-physical address */ |
| 25 | typedef struct xpaddr { |
| 26 | phys_addr_t paddr; |
| 27 | } xpaddr_t; |
| 28 | |
| 29 | #ifdef CONFIG_X86_64 |
| 30 | #define XEN_PHYSICAL_MASK __sme_clr((1UL << 52) - 1) |
| 31 | #else |
| 32 | #define XEN_PHYSICAL_MASK __PHYSICAL_MASK |
| 33 | #endif |
| 34 | |
| 35 | #define XEN_PTE_MFN_MASK ((pteval_t)(((signed long)PAGE_MASK) & \ |
| 36 | XEN_PHYSICAL_MASK)) |
| 37 | |
| 38 | #define XMADDR(x) ((xmaddr_t) { .maddr = (x) }) |
| 39 | #define XPADDR(x) ((xpaddr_t) { .paddr = (x) }) |
| 40 | |
| 41 | /**** MACHINE <-> PHYSICAL CONVERSION MACROS ****/ |
| 42 | #define INVALID_P2M_ENTRY (~0UL) |
| 43 | #define FOREIGN_FRAME_BIT (1UL<<(BITS_PER_LONG-1)) |
| 44 | #define IDENTITY_FRAME_BIT (1UL<<(BITS_PER_LONG-2)) |
| 45 | #define FOREIGN_FRAME(m) ((m) | FOREIGN_FRAME_BIT) |
| 46 | #define IDENTITY_FRAME(m) ((m) | IDENTITY_FRAME_BIT) |
| 47 | |
| 48 | #define P2M_PER_PAGE (PAGE_SIZE / sizeof(unsigned long)) |
| 49 | |
| 50 | extern unsigned long *machine_to_phys_mapping; |
| 51 | extern unsigned long machine_to_phys_nr; |
| 52 | extern unsigned long *xen_p2m_addr; |
| 53 | extern unsigned long xen_p2m_size; |
| 54 | extern unsigned long xen_max_p2m_pfn; |
| 55 | |
| 56 | extern int xen_alloc_p2m_entry(unsigned long pfn); |
| 57 | |
| 58 | extern unsigned long get_phys_to_machine(unsigned long pfn); |
| 59 | extern bool set_phys_to_machine(unsigned long pfn, unsigned long mfn); |
| 60 | extern bool __set_phys_to_machine(unsigned long pfn, unsigned long mfn); |
| 61 | extern unsigned long __init set_phys_range_identity(unsigned long pfn_s, |
| 62 | unsigned long pfn_e); |
| 63 | |
| 64 | #ifdef CONFIG_XEN_PV |
| 65 | extern int set_foreign_p2m_mapping(struct gnttab_map_grant_ref *map_ops, |
| 66 | struct gnttab_map_grant_ref *kmap_ops, |
| 67 | struct page **pages, unsigned int count); |
| 68 | extern int clear_foreign_p2m_mapping(struct gnttab_unmap_grant_ref *unmap_ops, |
| 69 | struct gnttab_unmap_grant_ref *kunmap_ops, |
| 70 | struct page **pages, unsigned int count); |
| 71 | #else |
| 72 | static inline int |
| 73 | set_foreign_p2m_mapping(struct gnttab_map_grant_ref *map_ops, |
| 74 | struct gnttab_map_grant_ref *kmap_ops, |
| 75 | struct page **pages, unsigned int count) |
| 76 | { |
| 77 | return 0; |
| 78 | } |
| 79 | |
| 80 | static inline int |
| 81 | clear_foreign_p2m_mapping(struct gnttab_unmap_grant_ref *unmap_ops, |
| 82 | struct gnttab_unmap_grant_ref *kunmap_ops, |
| 83 | struct page **pages, unsigned int count) |
| 84 | { |
| 85 | return 0; |
| 86 | } |
| 87 | #endif |
| 88 | |
| 89 | /* |
| 90 | * Helper functions to write or read unsigned long values to/from |
| 91 | * memory, when the access may fault. |
| 92 | */ |
| 93 | static inline int xen_safe_write_ulong(unsigned long *addr, unsigned long val) |
| 94 | { |
| 95 | int ret = 0; |
| 96 | |
| 97 | asm volatile("1: mov %[val], %[ptr]\n" |
| 98 | "2:\n" |
| 99 | _ASM_EXTABLE_TYPE_REG(1b, 2b, EX_TYPE_EFAULT_REG, %[ret]) |
| 100 | : [ret] "+r" (ret), [ptr] "=m" (*addr) |
| 101 | : [val] "r" (val)); |
| 102 | |
| 103 | return ret; |
| 104 | } |
| 105 | |
| 106 | static inline int xen_safe_read_ulong(const unsigned long *addr, |
| 107 | unsigned long *val) |
| 108 | { |
| 109 | unsigned long rval = ~0ul; |
| 110 | int ret = 0; |
| 111 | |
| 112 | asm volatile("1: mov %[ptr], %[rval]\n" |
| 113 | "2:\n" |
| 114 | _ASM_EXTABLE_TYPE_REG(1b, 2b, EX_TYPE_EFAULT_REG, %[ret]) |
| 115 | : [ret] "+r" (ret), [rval] "+r" (rval) |
| 116 | : [ptr] "m" (*addr)); |
| 117 | *val = rval; |
| 118 | |
| 119 | return ret; |
| 120 | } |
| 121 | |
| 122 | #ifdef CONFIG_XEN_PV |
| 123 | /* |
| 124 | * When to use pfn_to_mfn(), __pfn_to_mfn() or get_phys_to_machine(): |
| 125 | * - pfn_to_mfn() returns either INVALID_P2M_ENTRY or the mfn. No indicator |
| 126 | * bits (identity or foreign) are set. |
| 127 | * - __pfn_to_mfn() returns the found entry of the p2m table. A possibly set |
| 128 | * identity or foreign indicator will be still set. __pfn_to_mfn() is |
| 129 | * encapsulating get_phys_to_machine() which is called in special cases only. |
| 130 | * - get_phys_to_machine() is to be called by __pfn_to_mfn() only in special |
| 131 | * cases needing an extended handling. |
| 132 | */ |
| 133 | static inline unsigned long __pfn_to_mfn(unsigned long pfn) |
| 134 | { |
| 135 | unsigned long mfn; |
| 136 | |
| 137 | if (pfn < xen_p2m_size) |
| 138 | mfn = xen_p2m_addr[pfn]; |
| 139 | else if (unlikely(pfn < xen_max_p2m_pfn)) |
| 140 | return get_phys_to_machine(pfn); |
| 141 | else |
| 142 | return IDENTITY_FRAME(pfn); |
| 143 | |
| 144 | if (unlikely(mfn == INVALID_P2M_ENTRY)) |
| 145 | return get_phys_to_machine(pfn); |
| 146 | |
| 147 | return mfn; |
| 148 | } |
| 149 | #else |
| 150 | static inline unsigned long __pfn_to_mfn(unsigned long pfn) |
| 151 | { |
| 152 | return pfn; |
| 153 | } |
| 154 | #endif |
| 155 | |
| 156 | static inline unsigned long pfn_to_mfn(unsigned long pfn) |
| 157 | { |
| 158 | unsigned long mfn; |
| 159 | |
| 160 | /* |
| 161 | * Some x86 code are still using pfn_to_mfn instead of |
| 162 | * pfn_to_mfn. This will have to be removed when we figured |
| 163 | * out which call. |
| 164 | */ |
| 165 | if (xen_feature(XENFEAT_auto_translated_physmap)) |
| 166 | return pfn; |
| 167 | |
| 168 | mfn = __pfn_to_mfn(pfn); |
| 169 | |
| 170 | if (mfn != INVALID_P2M_ENTRY) |
| 171 | mfn &= ~(FOREIGN_FRAME_BIT | IDENTITY_FRAME_BIT); |
| 172 | |
| 173 | return mfn; |
| 174 | } |
| 175 | |
| 176 | static inline int phys_to_machine_mapping_valid(unsigned long pfn) |
| 177 | { |
| 178 | if (xen_feature(XENFEAT_auto_translated_physmap)) |
| 179 | return 1; |
| 180 | |
| 181 | return __pfn_to_mfn(pfn) != INVALID_P2M_ENTRY; |
| 182 | } |
| 183 | |
| 184 | static inline unsigned long mfn_to_pfn_no_overrides(unsigned long mfn) |
| 185 | { |
| 186 | unsigned long pfn; |
| 187 | int ret; |
| 188 | |
| 189 | if (unlikely(mfn >= machine_to_phys_nr)) |
| 190 | return ~0; |
| 191 | |
| 192 | /* |
| 193 | * The array access can fail (e.g., device space beyond end of RAM). |
| 194 | * In such cases it doesn't matter what we return (we return garbage), |
| 195 | * but we must handle the fault without crashing! |
| 196 | */ |
| 197 | ret = xen_safe_read_ulong(&machine_to_phys_mapping[mfn], &pfn); |
| 198 | if (ret < 0) |
| 199 | return ~0; |
| 200 | |
| 201 | return pfn; |
| 202 | } |
| 203 | |
| 204 | static inline unsigned long mfn_to_pfn(unsigned long mfn) |
| 205 | { |
| 206 | unsigned long pfn; |
| 207 | |
| 208 | /* |
| 209 | * Some x86 code are still using mfn_to_pfn instead of |
| 210 | * gfn_to_pfn. This will have to be removed when we figure |
| 211 | * out which call. |
| 212 | */ |
| 213 | if (xen_feature(XENFEAT_auto_translated_physmap)) |
| 214 | return mfn; |
| 215 | |
| 216 | pfn = mfn_to_pfn_no_overrides(mfn); |
| 217 | if (__pfn_to_mfn(pfn) != mfn) |
| 218 | pfn = ~0; |
| 219 | |
| 220 | /* |
| 221 | * pfn is ~0 if there are no entries in the m2p for mfn or the |
| 222 | * entry doesn't map back to the mfn. |
| 223 | */ |
| 224 | if (pfn == ~0 && __pfn_to_mfn(mfn) == IDENTITY_FRAME(mfn)) |
| 225 | pfn = mfn; |
| 226 | |
| 227 | return pfn; |
| 228 | } |
| 229 | |
| 230 | static inline xmaddr_t phys_to_machine(xpaddr_t phys) |
| 231 | { |
| 232 | unsigned offset = phys.paddr & ~PAGE_MASK; |
| 233 | return XMADDR(PFN_PHYS(pfn_to_mfn(PFN_DOWN(phys.paddr))) | offset); |
| 234 | } |
| 235 | |
| 236 | static inline xpaddr_t machine_to_phys(xmaddr_t machine) |
| 237 | { |
| 238 | unsigned offset = machine.maddr & ~PAGE_MASK; |
| 239 | return XPADDR(PFN_PHYS(mfn_to_pfn(PFN_DOWN(machine.maddr))) | offset); |
| 240 | } |
| 241 | |
| 242 | /* Pseudo-physical <-> Guest conversion */ |
| 243 | static inline unsigned long pfn_to_gfn(unsigned long pfn) |
| 244 | { |
| 245 | if (xen_feature(XENFEAT_auto_translated_physmap)) |
| 246 | return pfn; |
| 247 | else |
| 248 | return pfn_to_mfn(pfn); |
| 249 | } |
| 250 | |
| 251 | static inline unsigned long gfn_to_pfn(unsigned long gfn) |
| 252 | { |
| 253 | if (xen_feature(XENFEAT_auto_translated_physmap)) |
| 254 | return gfn; |
| 255 | else |
| 256 | return mfn_to_pfn(gfn); |
| 257 | } |
| 258 | |
| 259 | /* Pseudo-physical <-> Bus conversion */ |
| 260 | #define pfn_to_bfn(pfn) pfn_to_gfn(pfn) |
| 261 | #define bfn_to_pfn(bfn) gfn_to_pfn(bfn) |
| 262 | |
| 263 | /* |
| 264 | * We detect special mappings in one of two ways: |
| 265 | * 1. If the MFN is an I/O page then Xen will set the m2p entry |
| 266 | * to be outside our maximum possible pseudophys range. |
| 267 | * 2. If the MFN belongs to a different domain then we will certainly |
| 268 | * not have MFN in our p2m table. Conversely, if the page is ours, |
| 269 | * then we'll have p2m(m2p(MFN))==MFN. |
| 270 | * If we detect a special mapping then it doesn't have a 'struct page'. |
| 271 | * We force !pfn_valid() by returning an out-of-range pointer. |
| 272 | * |
| 273 | * NB. These checks require that, for any MFN that is not in our reservation, |
| 274 | * there is no PFN such that p2m(PFN) == MFN. Otherwise we can get confused if |
| 275 | * we are foreign-mapping the MFN, and the other domain as m2p(MFN) == PFN. |
| 276 | * Yikes! Various places must poke in INVALID_P2M_ENTRY for safety. |
| 277 | * |
| 278 | * NB2. When deliberately mapping foreign pages into the p2m table, you *must* |
| 279 | * use FOREIGN_FRAME(). This will cause pte_pfn() to choke on it, as we |
| 280 | * require. In all the cases we care about, the FOREIGN_FRAME bit is |
| 281 | * masked (e.g., pfn_to_mfn()) so behaviour there is correct. |
| 282 | */ |
| 283 | static inline unsigned long bfn_to_local_pfn(unsigned long mfn) |
| 284 | { |
| 285 | unsigned long pfn; |
| 286 | |
| 287 | if (xen_feature(XENFEAT_auto_translated_physmap)) |
| 288 | return mfn; |
| 289 | |
| 290 | pfn = mfn_to_pfn(mfn); |
| 291 | if (__pfn_to_mfn(pfn) != mfn) |
| 292 | return -1; /* force !pfn_valid() */ |
| 293 | return pfn; |
| 294 | } |
| 295 | |
| 296 | /* VIRT <-> MACHINE conversion */ |
| 297 | #define virt_to_machine(v) (phys_to_machine(XPADDR(__pa(v)))) |
| 298 | static inline unsigned long virt_to_pfn(const void *v) |
| 299 | { |
| 300 | return PFN_DOWN(__pa(v)); |
| 301 | } |
| 302 | #define virt_to_mfn(v) (pfn_to_mfn(virt_to_pfn(v))) |
| 303 | #define mfn_to_virt(m) (__va(mfn_to_pfn(m) << PAGE_SHIFT)) |
| 304 | |
| 305 | /* VIRT <-> GUEST conversion */ |
| 306 | #define virt_to_gfn(v) (pfn_to_gfn(virt_to_pfn(v))) |
| 307 | #define gfn_to_virt(g) (__va(gfn_to_pfn(g) << PAGE_SHIFT)) |
| 308 | |
| 309 | static inline unsigned long pte_mfn(pte_t pte) |
| 310 | { |
| 311 | return (pte.pte & XEN_PTE_MFN_MASK) >> PAGE_SHIFT; |
| 312 | } |
| 313 | |
| 314 | static inline pte_t mfn_pte(unsigned long page_nr, pgprot_t pgprot) |
| 315 | { |
| 316 | pte_t pte; |
| 317 | |
| 318 | pte.pte = ((phys_addr_t)page_nr << PAGE_SHIFT) | |
| 319 | massage_pgprot(pgprot); |
| 320 | |
| 321 | return pte; |
| 322 | } |
| 323 | |
| 324 | static inline pteval_t pte_val_ma(pte_t pte) |
| 325 | { |
| 326 | return pte.pte; |
| 327 | } |
| 328 | |
| 329 | static inline pte_t __pte_ma(pteval_t x) |
| 330 | { |
| 331 | return (pte_t) { .pte = x }; |
| 332 | } |
| 333 | |
| 334 | #define pmd_val_ma(v) ((v).pmd) |
| 335 | #ifdef __PAGETABLE_PUD_FOLDED |
| 336 | #define pud_val_ma(v) ((v).p4d.pgd.pgd) |
| 337 | #else |
| 338 | #define pud_val_ma(v) ((v).pud) |
| 339 | #endif |
| 340 | #define __pmd_ma(x) ((pmd_t) { (x) } ) |
| 341 | |
| 342 | #ifdef __PAGETABLE_P4D_FOLDED |
| 343 | #define p4d_val_ma(x) ((x).pgd.pgd) |
| 344 | #else |
| 345 | #define p4d_val_ma(x) ((x).p4d) |
| 346 | #endif |
| 347 | |
| 348 | xmaddr_t arbitrary_virt_to_machine(void *address); |
| 349 | unsigned long arbitrary_virt_to_mfn(void *vaddr); |
| 350 | void make_lowmem_page_readonly(void *vaddr); |
| 351 | void make_lowmem_page_readwrite(void *vaddr); |
| 352 | |
| 353 | static inline bool xen_arch_need_swiotlb(struct device *dev, |
| 354 | phys_addr_t phys, |
| 355 | dma_addr_t dev_addr) |
| 356 | { |
| 357 | return false; |
| 358 | } |
| 359 | |
| 360 | #endif /* _ASM_X86_XEN_PAGE_H */ |