43,19 → 43,21 |
#include <genarch/mm/page_ht.h> |
#include <mm/asid.h> |
#include <arch/mm/asid.h> |
#include <arch/types.h> |
#include <typedefs.h> |
#include <synch/spinlock.h> |
#include <config.h> |
#include <adt/list.h> |
#include <adt/btree.h> |
#include <proc/task.h> |
#include <arch/asm.h> |
#include <panic.h> |
#include <arch/asm.h> |
#include <debug.h> |
#include <print.h> |
#include <memstr.h> |
#include <macros.h> |
#include <arch.h> |
#include <print.h> |
#include <errno.h> |
#include <config.h> |
#include <arch/types.h> |
#include <typedefs.h> |
|
as_operations_t *as_operations = NULL; |
|
71,6 → 73,7 |
/** Kernel address space. */ |
as_t *AS_KERNEL = NULL; |
|
static int area_flags_to_page_flags(int aflags); |
static int get_area_flags(as_area_t *a); |
static as_area_t *find_area_and_lock(as_t *as, __address va); |
static bool check_area_conflicts(as_t *as, __address va, size_t size, as_area_t *avoid_area); |
169,6 → 172,246 |
return a; |
} |
|
/** Find address space area and change it. |
* |
* @param as Address space. |
* @param address Virtual address belonging to the area to be changed. Must be page-aligned. |
* @param size New size of the virtual memory block starting at address. |
* @param flags Flags influencing the remap operation. Currently unused. |
* |
* @return address on success, (__address) -1 otherwise. |
*/ |
__address as_area_resize(as_t *as, __address address, size_t size, int flags) |
{ |
as_area_t *area = NULL; |
ipl_t ipl; |
size_t pages; |
|
ipl = interrupts_disable(); |
spinlock_lock(&as->lock); |
|
/* |
* Locate the area. |
*/ |
area = find_area_and_lock(as, address); |
if (!area) { |
spinlock_unlock(&as->lock); |
interrupts_restore(ipl); |
return (__address) -1; |
} |
|
if (area->flags & AS_AREA_DEVICE) { |
/* |
* Remapping of address space areas associated |
* with memory mapped devices is not supported. |
*/ |
spinlock_unlock(&area->lock); |
spinlock_unlock(&as->lock); |
interrupts_restore(ipl); |
return (__address) -1; |
} |
|
pages = SIZE2FRAMES((address - area->base) + size); |
if (!pages) { |
/* |
* Zero size address space areas are not allowed. |
*/ |
spinlock_unlock(&area->lock); |
spinlock_unlock(&as->lock); |
interrupts_restore(ipl); |
return (__address) -1; |
} |
|
if (pages < area->pages) { |
int i; |
|
/* |
* Shrinking the area. |
* No need to check for overlaps. |
*/ |
for (i = pages; i < area->pages; i++) { |
pte_t *pte; |
|
/* |
* Releasing physical memory. |
* This depends on the fact that the memory was allocated using frame_alloc(). |
*/ |
page_table_lock(as, false); |
pte = page_mapping_find(as, area->base + i*PAGE_SIZE); |
if (pte && PTE_VALID(pte)) { |
__address frame; |
|
ASSERT(PTE_PRESENT(pte)); |
frame = PTE_GET_FRAME(pte); |
page_mapping_remove(as, area->base + i*PAGE_SIZE); |
page_table_unlock(as, false); |
|
frame_free(ADDR2PFN(frame)); |
} else { |
page_table_unlock(as, false); |
} |
} |
/* |
* Invalidate TLB's. |
*/ |
tlb_shootdown_start(TLB_INVL_PAGES, AS->asid, area->base + pages*PAGE_SIZE, area->pages - pages); |
tlb_invalidate_pages(AS->asid, area->base + pages*PAGE_SIZE, area->pages - pages); |
tlb_shootdown_finalize(); |
} else { |
/* |
* Growing the area. |
* Check for overlaps with other address space areas. |
*/ |
if (!check_area_conflicts(as, address, pages * PAGE_SIZE, area)) { |
spinlock_unlock(&area->lock); |
spinlock_unlock(&as->lock); |
interrupts_restore(ipl); |
return (__address) -1; |
} |
} |
|
area->pages = pages; |
|
spinlock_unlock(&area->lock); |
spinlock_unlock(&as->lock); |
interrupts_restore(ipl); |
|
return address; |
} |
|
/** Send address space area to another task. |
* |
* Address space area is sent to the specified task. |
* If the destination task is willing to accept the |
* area, a new area is created according to the |
* source area. Moreover, any existing mapping |
* is copied as well, providing thus a mechanism |
* for sharing group of pages. The source address |
* space area and any associated mapping is preserved. |
* |
* @param id Task ID of the accepting task. |
* @param base Base address of the source address space area. |
* @param size Size of the source address space area. |
* @param flags Flags of the source address space area. |
* |
* @return 0 on success or ENOENT if there is no such task or |
* if there is no such address space area, |
* EPERM if there was a problem in accepting the area or |
* ENOMEM if there was a problem in allocating destination |
* address space area. |
*/ |
int as_area_send(task_id_t id, __address base, size_t size, int flags) |
{ |
ipl_t ipl; |
task_t *t; |
count_t i; |
as_t *as; |
__address dst_base; |
|
ipl = interrupts_disable(); |
spinlock_lock(&tasks_lock); |
|
t = task_find_by_id(id); |
if (!NULL) { |
spinlock_unlock(&tasks_lock); |
interrupts_restore(ipl); |
return ENOENT; |
} |
|
spinlock_lock(&t->lock); |
spinlock_unlock(&tasks_lock); |
|
as = t->as; |
dst_base = (__address) t->accept_arg.base; |
|
if (as == AS) { |
/* |
* The two tasks share the entire address space. |
* Return error since there is no point in continuing. |
*/ |
spinlock_unlock(&t->lock); |
interrupts_restore(ipl); |
return EPERM; |
} |
|
if ((t->accept_arg.task_id != TASK->taskid) || (t->accept_arg.size != size) || |
(t->accept_arg.flags != flags)) { |
/* |
* Discrepancy in either task ID, size or flags. |
*/ |
spinlock_unlock(&t->lock); |
interrupts_restore(ipl); |
return EPERM; |
} |
|
/* |
* Create copy of the address space area. |
*/ |
if (!as_area_create(as, flags, size, dst_base)) { |
/* |
* Destination address space area could not be created. |
*/ |
spinlock_unlock(&t->lock); |
interrupts_restore(ipl); |
return ENOMEM; |
} |
|
/* |
* NOTE: we have just introduced a race condition. |
* The destination task can try to attempt the newly |
* created area before its mapping is copied from |
* the source address space area. In result, frames |
* can get lost. |
* |
* Currently, this race is not solved, but one of the |
* possible solutions would be to sleep in as_page_fault() |
* when this situation is detected. |
*/ |
|
memsetb((__address) &t->accept_arg, sizeof(as_area_acptsnd_arg_t), 0); |
spinlock_unlock(&t->lock); |
|
/* |
* Avoid deadlock by first locking the address space with lower address. |
*/ |
if (as < AS) { |
spinlock_lock(&as->lock); |
spinlock_lock(&AS->lock); |
} else { |
spinlock_lock(&AS->lock); |
spinlock_lock(&as->lock); |
} |
|
for (i = 0; i < SIZE2FRAMES(size); i++) { |
pte_t *pte; |
__address frame; |
|
page_table_lock(AS, false); |
pte = page_mapping_find(AS, base + i*PAGE_SIZE); |
if (pte && PTE_VALID(pte)) { |
ASSERT(PTE_PRESENT(pte)); |
frame = PTE_GET_FRAME(pte); |
if (!(flags & AS_AREA_DEVICE)) { |
/* TODO: increment frame reference count */ |
} |
page_table_unlock(AS, false); |
} else { |
page_table_unlock(AS, false); |
continue; |
} |
|
page_table_lock(as, false); |
page_mapping_insert(as, dst_base + i*PAGE_SIZE, frame, area_flags_to_page_flags(flags)); |
page_table_unlock(as, false); |
} |
|
spinlock_unlock(&AS->lock); |
spinlock_unlock(&as->lock); |
interrupts_restore(ipl); |
|
return 0; |
} |
|
/** Initialize mapping for one page of address space. |
* |
* This functions maps 'page' to 'frame' according |
344,36 → 587,47 |
AS = new; |
} |
|
/** Compute flags for virtual address translation subsytem. |
/** Convert address space area flags to page flags. |
* |
* The address space area must be locked. |
* Interrupts must be disabled. |
* @param aflags Flags of some address space area. |
* |
* @param a Address space area. |
* |
* @return Flags to be used in page_mapping_insert(). |
* @return Flags to be passed to page_mapping_insert(). |
*/ |
int get_area_flags(as_area_t *a) |
int area_flags_to_page_flags(int aflags) |
{ |
int flags; |
|
flags = PAGE_USER | PAGE_PRESENT; |
|
if (a->flags & AS_AREA_READ) |
if (aflags & AS_AREA_READ) |
flags |= PAGE_READ; |
|
if (a->flags & AS_AREA_WRITE) |
if (aflags & AS_AREA_WRITE) |
flags |= PAGE_WRITE; |
|
if (a->flags & AS_AREA_EXEC) |
if (aflags & AS_AREA_EXEC) |
flags |= PAGE_EXEC; |
|
if (!(a->flags & AS_AREA_DEVICE)) |
if (!(aflags & AS_AREA_DEVICE)) |
flags |= PAGE_CACHEABLE; |
|
return flags; |
} |
|
/** Compute flags for virtual address translation subsytem. |
* |
* The address space area must be locked. |
* Interrupts must be disabled. |
* |
* @param a Address space area. |
* |
* @return Flags to be used in page_mapping_insert(). |
*/ |
int get_area_flags(as_area_t *a) |
{ |
return area_flags_to_page_flags(a->flags); |
} |
|
/** Create page table. |
* |
* Depending on architecture, create either address space |
424,113 → 678,7 |
as_operations->page_table_unlock(as, unlock); |
} |
|
/** Find address space area and change it. |
* |
* @param as Address space. |
* @param address Virtual address belonging to the area to be changed. Must be page-aligned. |
* @param size New size of the virtual memory block starting at address. |
* @param flags Flags influencing the remap operation. Currently unused. |
* |
* @return address on success, (__address) -1 otherwise. |
*/ |
__address as_area_resize(as_t *as, __address address, size_t size, int flags) |
{ |
as_area_t *area = NULL; |
ipl_t ipl; |
size_t pages; |
|
ipl = interrupts_disable(); |
spinlock_lock(&as->lock); |
|
/* |
* Locate the area. |
*/ |
area = find_area_and_lock(as, address); |
if (!area) { |
spinlock_unlock(&as->lock); |
interrupts_restore(ipl); |
return (__address) -1; |
} |
|
if (area->flags & AS_AREA_DEVICE) { |
/* |
* Remapping of address space areas associated |
* with memory mapped devices is not supported. |
*/ |
spinlock_unlock(&area->lock); |
spinlock_unlock(&as->lock); |
interrupts_restore(ipl); |
return (__address) -1; |
} |
|
pages = SIZE2FRAMES((address - area->base) + size); |
if (!pages) { |
/* |
* Zero size address space areas are not allowed. |
*/ |
spinlock_unlock(&area->lock); |
spinlock_unlock(&as->lock); |
interrupts_restore(ipl); |
return (__address) -1; |
} |
|
if (pages < area->pages) { |
int i; |
|
/* |
* Shrinking the area. |
* No need to check for overlaps. |
*/ |
for (i = pages; i < area->pages; i++) { |
pte_t *pte; |
|
/* |
* Releasing physical memory. |
* This depends on the fact that the memory was allocated using frame_alloc(). |
*/ |
page_table_lock(as, false); |
pte = page_mapping_find(as, area->base + i*PAGE_SIZE); |
if (pte && PTE_VALID(pte)) { |
__address frame; |
|
ASSERT(PTE_PRESENT(pte)); |
frame = PTE_GET_FRAME(pte); |
page_mapping_remove(as, area->base + i*PAGE_SIZE); |
page_table_unlock(as, false); |
|
frame_free(ADDR2PFN(frame)); |
} else { |
page_table_unlock(as, false); |
} |
} |
/* |
* Invalidate TLB's. |
*/ |
tlb_shootdown_start(TLB_INVL_PAGES, AS->asid, area->base + pages*PAGE_SIZE, area->pages - pages); |
tlb_invalidate_pages(AS->asid, area->base + pages*PAGE_SIZE, area->pages - pages); |
tlb_shootdown_finalize(); |
} else { |
/* |
* Growing the area. |
* Check for overlaps with other address space areas. |
*/ |
if (!check_area_conflicts(as, address, pages * PAGE_SIZE, area)) { |
spinlock_unlock(&area->lock); |
spinlock_unlock(&as->lock); |
interrupts_restore(ipl); |
return (__address) -1; |
} |
} |
|
area->pages = pages; |
|
spinlock_unlock(&area->lock); |
spinlock_unlock(&as->lock); |
interrupts_restore(ipl); |
|
return address; |
} |
|
/** Find address space area and lock it. |
* |
* The address space must be locked and interrupts must be disabled. |
667,3 → 815,70 |
|
return true; |
} |
|
/* |
* Address space related syscalls. |
*/ |
|
/** Wrapper for as_area_create(). */ |
__native sys_as_area_create(__address address, size_t size, int flags) |
{ |
if (as_area_create(AS, flags, size, address)) |
return (__native) address; |
else |
return (__native) -1; |
} |
|
/** Wrapper for as_area_resize. */ |
__native sys_as_area_resize(__address address, size_t size, int flags) |
{ |
return as_area_resize(AS, address, size, 0); |
} |
|
/** Prepare task for accepting address space area from another task. |
* |
* @param uspace_accept_arg Accept structure passed from userspace. |
* |
* @return EPERM if the task ID encapsulated in @uspace_accept_arg references |
* TASK. Otherwise zero is returned. |
*/ |
__native sys_as_area_accept(as_area_acptsnd_arg_t *uspace_accept_arg) |
{ |
as_area_acptsnd_arg_t arg; |
|
copy_from_uspace(&arg, uspace_accept_arg, sizeof(as_area_acptsnd_arg_t)); |
|
if (!arg.size) |
return (__native) EPERM; |
|
if (arg.task_id == TASK->taskid) { |
/* |
* Accepting from itself is not allowed. |
*/ |
return (__native) EPERM; |
} |
|
memcpy(&TASK->accept_arg, &arg, sizeof(as_area_acptsnd_arg_t)); |
|
return 0; |
} |
|
/** Wrapper for as_area_send. */ |
__native sys_as_area_send(as_area_acptsnd_arg_t *uspace_send_arg) |
{ |
as_area_acptsnd_arg_t arg; |
|
copy_from_uspace(&arg, uspace_send_arg, sizeof(as_area_acptsnd_arg_t)); |
|
if (!arg.size) |
return (__native) EPERM; |
|
if (arg.task_id == TASK->taskid) { |
/* |
* Sending to itself is not allowed. |
*/ |
return (__native) EPERM; |
} |
|
return (__native) as_area_send(arg.task_id, (__address) arg.base, arg.size, arg.flags); |
} |