diff options
Diffstat (limited to 'system/physmem.c')
| -rw-r--r-- | system/physmem.c | 121 |
1 files changed, 76 insertions, 45 deletions
diff --git a/system/physmem.c b/system/physmem.c index 67c9db9daa..67bdf631e6 100644 --- a/system/physmem.c +++ b/system/physmem.c @@ -573,7 +573,7 @@ MemoryRegion *flatview_translate(FlatView *fv, hwaddr addr, hwaddr *xlat, is_write, true, &as, attrs); mr = section.mr; - if (xen_enabled() && memory_access_is_direct(mr, is_write)) { + if (xen_enabled() && memory_access_is_direct(mr, is_write, attrs)) { hwaddr page = ((addr & TARGET_PAGE_MASK) + TARGET_PAGE_SIZE) - addr; *plen = MIN(page, *plen); } @@ -2275,45 +2275,80 @@ void qemu_ram_free(RAMBlock *block) } #ifndef _WIN32 -void qemu_ram_remap(ram_addr_t addr, ram_addr_t length) +/* Simply remap the given VM memory location from start to start+length */ +static int qemu_ram_remap_mmap(RAMBlock *block, uint64_t start, size_t length) +{ + int flags, prot; + void *area; + void *host_startaddr = block->host + start; + + assert(block->fd < 0); + flags = MAP_FIXED | MAP_ANONYMOUS; + flags |= block->flags & RAM_SHARED ? MAP_SHARED : MAP_PRIVATE; + flags |= block->flags & RAM_NORESERVE ? MAP_NORESERVE : 0; + prot = PROT_READ; + prot |= block->flags & RAM_READONLY ? 0 : PROT_WRITE; + area = mmap(host_startaddr, length, prot, flags, -1, 0); + return area != host_startaddr ? -errno : 0; +} + +/* + * qemu_ram_remap - remap a single RAM page + * + * @addr: address in ram_addr_t address space. + * + * This function will try remapping a single page of guest RAM identified by + * @addr, essentially discarding memory to recover from previously poisoned + * memory (MCE). The page size depends on the RAMBlock (i.e., hugetlb). @addr + * does not have to point at the start of the page. + * + * This function is only to be used during system resets; it will kill the + * VM if remapping failed. + */ +void qemu_ram_remap(ram_addr_t addr) { RAMBlock *block; - ram_addr_t offset; - int flags; - void *area, *vaddr; - int prot; + uint64_t offset; + void *vaddr; + size_t page_size; RAMBLOCK_FOREACH(block) { offset = addr - block->offset; if (offset < block->max_length) { + /* Respect the pagesize of our RAMBlock */ + page_size = qemu_ram_pagesize(block); + offset = QEMU_ALIGN_DOWN(offset, page_size); + vaddr = ramblock_ptr(block, offset); if (block->flags & RAM_PREALLOC) { ; } else if (xen_enabled()) { abort(); } else { - flags = MAP_FIXED; - flags |= block->flags & RAM_SHARED ? - MAP_SHARED : MAP_PRIVATE; - flags |= block->flags & RAM_NORESERVE ? MAP_NORESERVE : 0; - prot = PROT_READ; - prot |= block->flags & RAM_READONLY ? 0 : PROT_WRITE; - if (block->fd >= 0) { - area = mmap(vaddr, length, prot, flags, block->fd, - offset + block->fd_offset); - } else { - flags |= MAP_ANONYMOUS; - area = mmap(vaddr, length, prot, flags, -1, 0); - } - if (area != vaddr) { - error_report("Could not remap addr: " - RAM_ADDR_FMT "@" RAM_ADDR_FMT "", - length, addr); - exit(1); + if (ram_block_discard_range(block, offset, page_size) != 0) { + /* + * Fall back to using mmap() only for anonymous mapping, + * as if a backing file is associated we may not be able + * to recover the memory in all cases. + * So don't take the risk of using only mmap and fail now. + */ + if (block->fd >= 0) { + error_report("Could not remap RAM %s:%" PRIx64 "+%" + PRIx64 " +%zx", block->idstr, offset, + block->fd_offset, page_size); + exit(1); + } + if (qemu_ram_remap_mmap(block, offset, page_size) != 0) { + error_report("Could not remap RAM %s:%" PRIx64 " +%zx", + block->idstr, offset, page_size); + exit(1); + } } - memory_try_enable_merging(vaddr, length); - qemu_ram_setup_dump(vaddr, length); + memory_try_enable_merging(vaddr, page_size); + qemu_ram_setup_dump(vaddr, page_size); } + + break; } } } @@ -2869,7 +2904,7 @@ static MemTxResult flatview_write_continue_step(MemTxAttrs attrs, return MEMTX_ACCESS_ERROR; } - if (!memory_access_is_direct(mr, true)) { + if (!memory_access_is_direct(mr, true, attrs)) { uint64_t val; MemTxResult result; bool release_lock = prepare_mmio_access(mr); @@ -2965,7 +3000,7 @@ static MemTxResult flatview_read_continue_step(MemTxAttrs attrs, uint8_t *buf, return MEMTX_ACCESS_ERROR; } - if (!memory_access_is_direct(mr, false)) { + if (!memory_access_is_direct(mr, false, attrs)) { /* I/O case */ uint64_t val; MemTxResult result; @@ -3137,8 +3172,7 @@ static inline MemTxResult address_space_write_rom_internal(AddressSpace *as, l = len; mr = address_space_translate(as, addr, &addr1, &l, true, attrs); - if (!(memory_region_is_ram(mr) || - memory_region_is_romd(mr))) { + if (!memory_region_supports_direct_access(mr)) { l = memory_access_size(mr, l, addr1); } else { /* ROM/RAM case */ @@ -3275,7 +3309,7 @@ static bool flatview_access_valid(FlatView *fv, hwaddr addr, hwaddr len, while (len > 0) { l = len; mr = flatview_translate(fv, addr, &xlat, &l, is_write, attrs); - if (!memory_access_is_direct(mr, is_write)) { + if (!memory_access_is_direct(mr, is_write, attrs)) { l = memory_access_size(mr, l, addr); if (!memory_region_access_valid(mr, xlat, l, is_write, attrs)) { return false; @@ -3355,7 +3389,7 @@ void *address_space_map(AddressSpace *as, fv = address_space_to_flatview(as); mr = flatview_translate(fv, addr, &xlat, &l, is_write, attrs); - if (!memory_access_is_direct(mr, is_write)) { + if (!memory_access_is_direct(mr, is_write, attrs)) { size_t used = qatomic_read(&as->bounce_buffer_size); for (;;) { hwaddr alloc = MIN(as->max_bounce_buffer_size - used, l); @@ -3488,7 +3522,7 @@ int64_t address_space_cache_init(MemoryRegionCache *cache, mr = cache->mrs.mr; memory_region_ref(mr); - if (memory_access_is_direct(mr, is_write)) { + if (memory_access_is_direct(mr, is_write, MEMTXATTRS_UNSPECIFIED)) { /* We don't care about the memory attributes here as we're only * doing this if we found actual RAM, which behaves the same * regardless of attributes; so UNSPECIFIED is fine. @@ -3681,13 +3715,8 @@ int cpu_memory_rw_debug(CPUState *cpu, vaddr addr, if (l > len) l = len; phys_addr += (addr & ~TARGET_PAGE_MASK); - if (is_write) { - res = address_space_write_rom(cpu->cpu_ases[asidx].as, phys_addr, - attrs, buf, l); - } else { - res = address_space_read(cpu->cpu_ases[asidx].as, phys_addr, - attrs, buf, l); - } + res = address_space_rw(cpu->cpu_ases[asidx].as, phys_addr, attrs, buf, + l, is_write); if (res != MEMTX_OK) { return -1; } @@ -3797,18 +3826,19 @@ int ram_block_discard_range(RAMBlock *rb, uint64_t start, size_t length) } ret = fallocate(rb->fd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, - start, length); + start + rb->fd_offset, length); if (ret) { ret = -errno; - error_report("%s: Failed to fallocate %s:%" PRIx64 " +%zx (%d)", - __func__, rb->idstr, start, length, ret); + error_report("%s: Failed to fallocate %s:%" PRIx64 "+%" PRIx64 + " +%zx (%d)", __func__, rb->idstr, start, + rb->fd_offset, length, ret); goto err; } #else ret = -ENOSYS; error_report("%s: fallocate not available/file" - "%s:%" PRIx64 " +%zx (%d)", - __func__, rb->idstr, start, length, ret); + "%s:%" PRIx64 "+%" PRIx64 " +%zx (%d)", __func__, + rb->idstr, start, rb->fd_offset, length, ret); goto err; #endif } @@ -3855,6 +3885,7 @@ int ram_block_discard_guest_memfd_range(RAMBlock *rb, uint64_t start, int ret = -1; #ifdef CONFIG_FALLOCATE_PUNCH_HOLE + /* ignore fd_offset with guest_memfd */ ret = fallocate(rb->guest_memfd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, start, length); |