diff options
| -rw-r--r-- | kc/core/memory.c | 132 | ||||
| -rw-r--r-- | kc/core/memory.h | 3 |
2 files changed, 77 insertions, 58 deletions
diff --git a/kc/core/memory.c b/kc/core/memory.c index 64206cf..fccada9 100644 --- a/kc/core/memory.c +++ b/kc/core/memory.c @@ -52,9 +52,9 @@ struct page enum vm_object_type { - NULL_VM_OBJECT, - TRANSLATION_VM_OBJECT, - ANONYMOUS_VM_OBJECT + NULL_VM_OBJECT, // a non-object. shouldn't even exist. an abomination unto man and god + TRANSLATION_VM_OBJECT, // a direct mapping between a physical and virtual address range + ANONYMOUS_VM_OBJECT, // a mapping that has no definite physical location }; struct vm_object @@ -91,7 +91,8 @@ static struct vm_object core_vmobject = {.type = ANONYMOUS_VM_OBJECT}; static size_t vm_object_space_size = 0x1000000; // 16MiB to start. static void *vm_next_free = NULL; -static struct memory_range init_grab_pages(struct memory_range *ranges, +static struct memory_range init_grab_pages( + struct memory_range *ranges, int count, size_t size) { @@ -453,23 +454,36 @@ void heap_free(void *block) void *memory_alloc(size_t size) { - (void)size; - return NULL; + // allocations larger than page-size should just get an anonymous vm_object + if (size < 4096) + { + return heap_alloc(size); + } + else + { + return vm_alloc(size); + } } void memory_free(void *block) { + // a little complicated to implement + // + // 1. find the vm_object that owns the block + // a. if the vm_object is a heap, call heap_free() + // b. if the vm_object is an anonymous vm_area, call vm_free(). + // c. if the object is any other kind issue a bug warning and do nothing (void)block; } -struct vm_tree_node *vm_alloc_at(void *address, size_t size) +void *vm_alloc_at(void *address, size_t size) { (void)address; (void)size; return NULL; } -struct vm_tree_node *vm_alloc(size_t size) +void *vm_alloc(size_t size) { (void)size; return NULL; @@ -485,68 +499,71 @@ static uint64_t *get_kernel_pm2e(void *vaddr) return &kernel_pm2[kpm2_index(vaddr)]; } -/* - int anonymous_page_handler(uint32_t code, void *address) - { - kputs("anonymous space fault\n"); - if (code & PAGE_PR) - { -// there's no reason a protection violation should happen -// in anonymous space -panic(UNHANDLED_FAULT); -} -// kernel page mappings are built different -if (address >= (void *)&kc_image_base) -{ -uint64_t *pm2e = get_kernel_pm2e(address); -if (!page_address(*pm2e, 1)) -{ -// create a page table and install it -phys_addr_t pm1_phys = page_alloc(); -if (pm1_phys) +int anonymous_page_handler(uint32_t code, void *address) { -uint64_t *pm1; -pm1 = page_map_at(temp, pm1_phys, CONTENT_RWDATA|SIZE_2M); -// zero the page -memset(pm1, 0, PAGE_SIZE); -// put the table where it goes - *pm2e = page_address(pm1_phys, 1)|PAGE_WR|PAGE_PR; - page_unmap(pm1); - } - else - { - panic(OUT_OF_MEMORY); - } - } + kputs("anonymous space fault\n"); + if (code & PAGE_PR) + { + // there's no reason a protection violation should happen + // in anonymous space + panic(UNHANDLED_FAULT); + } + // kernel page mappings are built different + if (address >= (void *)&kc_image_base) + { + uint64_t *pm2e = get_kernel_pm2e(address); + + if (!page_address(*pm2e, 1)) + { + // create a page table and install it + phys_addr_t pm1_phys = page_alloc(); + if (pm1_phys) + { + uint64_t *pm1; + pm1 = page_map_at(vm_temp, pm1_phys, CONTENT_RWDATA|SIZE_2M); + // zero the page + memset(pm1, 0, PAGE_SIZE); + // put the table where it goes + *pm2e = page_address(pm1_phys, 1)|PAGE_WR|PAGE_PR; + page_unmap(pm1); + } + else + { + panic(OUT_OF_MEMORY); + } + } - uint64_t *pm1e = get_kernel_pm1e(address); + uint64_t *pm1e = get_kernel_pm1e(address); - if (pm1e) - { - phys_addr_t page_phys = page_alloc(); - if (page_phys) - { - *pm1e = page_address(page_phys, 1)|PAGE_WR|PAGE_PR; -// clear a potentially dirty page. -memset((void *)page_address(address, 1), 0, page_size(1)); -} -} -} + if (pm1e) + { + phys_addr_t page_phys = page_alloc(); + if (page_phys) + { + *pm1e = page_address(page_phys, 1)|PAGE_WR|PAGE_PR; + // clear a potentially dirty page. + memset((void *)page_address(address, 1), 0, page_size(1)); + } + } + } -return 0; + return 0; } -*/ int page_fault_handler(uint32_t code, void *address) { (void)code; kputs("page fault\n"); struct vm_object *o = vmt_get_object(&core_vm_tree, address); + int result = 1; if (o) { kputs("found memory manager object\n"); - int result = 1; + if (o->handler) + { + result = o->handler(code, address); + } if (result) { panic(UNHANDLED_FAULT); @@ -557,6 +574,7 @@ int page_fault_handler(uint32_t code, void *address) kputs("didn't find memory object\n"); panic(UNHANDLED_FAULT); } + return 0; } @@ -569,8 +587,6 @@ static int core_image_handler(uint32_t code, void *address) static int core_vmobject_handler(uint32_t code, void *address) { - (void)code; - (void)address; - return 1; + return anonymous_page_handler(code, address); } diff --git a/kc/core/memory.h b/kc/core/memory.h index a4488cf..3f7f323 100644 --- a/kc/core/memory.h +++ b/kc/core/memory.h @@ -37,6 +37,9 @@ void page_free(phys_addr_t paddr); void *heap_alloc(size_t size); void heap_free(void *block); +void *vm_alloc(size_t size); +void vm_free(void *block); + void *memory_alloc(size_t size); void memory_free(void *block); |