38,6 → 38,9 |
#include <mm/as.h> |
#include <mm/frame.h> |
#include <mm/slab.h> |
#include <mm/page.h> |
#include <genarch/mm/page_pt.h> |
#include <genarch/mm/page_ht.h> |
#include <align.h> |
#include <memstr.h> |
#include <macros.h> |
45,11 → 48,12 |
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static int elf_page_fault(as_area_t *area, __address addr, pf_access_t access); |
static void elf_frame_free(as_area_t *area, __address page, __address frame); |
static void elf_share(as_area_t *area); |
|
mem_backend_t elf_backend = { |
.page_fault = elf_page_fault, |
.frame_free = elf_frame_free, |
.share = NULL |
.share = elf_share |
}; |
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/** Service a page fault in the ELF backend address space area. |
66,6 → 70,7 |
{ |
elf_header_t *elf = area->backend_data.elf; |
elf_segment_header_t *entry = area->backend_data.segment; |
btree_node_t *leaf; |
__address base, frame; |
index_t i; |
|
77,6 → 82,43 |
base = (__address) (((void *) elf) + entry->p_offset); |
ASSERT(ALIGN_UP(base, FRAME_SIZE) == base); |
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if (area->sh_info) { |
bool found = false; |
|
/* |
* The address space area is shared. |
*/ |
|
mutex_lock(&area->sh_info->lock); |
frame = (__address) btree_search(&area->sh_info->pagemap, |
ALIGN_DOWN(addr, PAGE_SIZE) - area->base, &leaf); |
if (!frame) { |
int i; |
|
/* |
* Workaround for valid NULL address. |
*/ |
|
for (i = 0; i < leaf->keys; i++) { |
if (leaf->key[i] == ALIGN_DOWN(addr, PAGE_SIZE)) { |
found = true; |
break; |
} |
} |
} |
if (frame || found) { |
page_mapping_insert(AS, addr, frame, as_area_get_flags(area)); |
if (!used_space_insert(area, ALIGN_DOWN(addr, PAGE_SIZE), 1)) |
panic("Could not insert used space.\n"); |
mutex_unlock(&area->sh_info->lock); |
return AS_PF_OK; |
} |
} |
|
/* |
* The area is either not shared or the pagemap does not contain the mapping. |
*/ |
|
if (ALIGN_DOWN(addr, PAGE_SIZE) + PAGE_SIZE < entry->p_vaddr + entry->p_filesz) { |
/* |
* Initialized portion of the segment. The memory is backed |
89,6 → 131,12 |
if (entry->p_flags & PF_W) { |
frame = PFN2ADDR(frame_alloc(ONE_FRAME, 0)); |
memcpy((void *) PA2KA(frame), (void *) (base + i*FRAME_SIZE), FRAME_SIZE); |
|
if (area->sh_info) { |
btree_insert(&area->sh_info->pagemap, ALIGN_DOWN(addr, PAGE_SIZE) - area->base, |
(void *) frame, leaf); |
} |
|
} else { |
frame = KA2PA(base + i*FRAME_SIZE); |
} |
101,6 → 149,12 |
*/ |
frame = PFN2ADDR(frame_alloc(ONE_FRAME, 0)); |
memsetb(PA2KA(frame), FRAME_SIZE, 0); |
|
if (area->sh_info) { |
btree_insert(&area->sh_info->pagemap, ALIGN_DOWN(addr, PAGE_SIZE) - area->base, |
(void *) frame, leaf); |
} |
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} else { |
size_t size; |
/* |
112,8 → 166,17 |
frame = PFN2ADDR(frame_alloc(ONE_FRAME, 0)); |
memsetb(PA2KA(frame) + size, FRAME_SIZE - size, 0); |
memcpy((void *) PA2KA(frame), (void *) (base + i*FRAME_SIZE), size); |
|
if (area->sh_info) { |
btree_insert(&area->sh_info->pagemap, ALIGN_DOWN(addr, PAGE_SIZE) - area->base, |
(void *) frame, leaf); |
} |
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} |
|
if (area->sh_info) |
mutex_unlock(&area->sh_info->lock); |
|
page_mapping_insert(AS, addr, frame, as_area_get_flags(area)); |
if (!used_space_insert(area, ALIGN_DOWN(addr, PAGE_SIZE), 1)) |
panic("Could not insert used space.\n"); |
158,3 → 221,77 |
frame_free(ADDR2PFN(frame)); |
} |
} |
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/** Share ELF image backed address space area. |
* |
* If the area is writable, then all mapped pages are duplicated in the pagemap. |
* Otherwise only portions of the area that are not backed by the ELF image |
* are put into the pagemap. |
* |
* The address space and address space area must be locked prior to the call. |
* |
* @param area Address space area. |
*/ |
void elf_share(as_area_t *area) |
{ |
elf_segment_header_t *entry = area->backend_data.segment; |
link_t *cur; |
btree_node_t *leaf, *node; |
__address start_anon = entry->p_vaddr + entry->p_filesz; |
|
/* |
* Find the node in which to start linear search. |
*/ |
if (area->flags & AS_AREA_WRITE) { |
node = list_get_instance(area->used_space.leaf_head.next, btree_node_t, leaf_link); |
} else { |
(void) btree_search(&area->sh_info->pagemap, start_anon, &leaf); |
node = btree_leaf_node_left_neighbour(&area->sh_info->pagemap, leaf); |
if (!node) |
node = leaf; |
} |
|
/* |
* Copy used anonymous portions of the area to sh_info's page map. |
*/ |
mutex_lock(&area->sh_info->lock); |
for (cur = &node->leaf_link; cur != &area->used_space.leaf_head; cur = cur->next) { |
int i; |
|
node = list_get_instance(cur, btree_node_t, leaf_link); |
|
for (i = 0; i < node->keys; i++) { |
__address base = node->key[i]; |
count_t count = (count_t) node->value[i]; |
int j; |
|
/* |
* Skip read-only areas of used space that are backed |
* by the ELF image. |
*/ |
if (!(area->flags & AS_AREA_WRITE)) |
if (base + count*PAGE_SIZE <= start_anon) |
continue; |
|
for (j = 0; j < count; j++) { |
pte_t *pte; |
|
/* |
* Skip read-only pages that are backed by the ELF image. |
*/ |
if (!(area->flags & AS_AREA_WRITE)) |
if (base + (j + 1)*PAGE_SIZE <= start_anon) |
continue; |
|
page_table_lock(area->as, false); |
pte = page_mapping_find(area->as, base + j*PAGE_SIZE); |
ASSERT(pte && PTE_VALID(pte) && PTE_PRESENT(pte)); |
btree_insert(&area->sh_info->pagemap, (base + j*PAGE_SIZE) - area->base, |
(void *) PTE_GET_FRAME(pte), NULL); |
page_table_unlock(area->as, false); |
} |
|
} |
} |
mutex_unlock(&area->sh_info->lock); |
} |