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Ignore whitespace Rev 2291 → Rev 2292

/branches/rcu/kernel/generic/src/mm/as.c
95,10 → 95,13
#endif
 
/**
* This lock protects inactive_as_with_asid_head list. It must be acquired
* before as_t mutex.
* This lock serializes access to the ASID subsystem.
* It protects:
* - inactive_as_with_asid_head list
* - as->asid for each as of the as_t type
* - asids_allocated counter
*/
SPINLOCK_INITIALIZE(inactive_as_with_asid_lock);
SPINLOCK_INITIALIZE(asidlock);
 
/**
* This list contains address spaces that are not active on any
205,14 → 208,15
* Since there is no reference to this area,
* it is safe not to lock its mutex.
*/
 
ipl = interrupts_disable();
spinlock_lock(&inactive_as_with_asid_lock);
spinlock_lock(&asidlock);
if (as->asid != ASID_INVALID && as != AS_KERNEL) {
if (as != AS && as->cpu_refcount == 0)
list_remove(&as->inactive_as_with_asid_link);
asid_put(as->asid);
}
spinlock_unlock(&inactive_as_with_asid_lock);
spinlock_unlock(&asidlock);
 
/*
* Destroy address space areas of the address space.
411,7 → 415,7
int i = 0;
if (overlaps(b, c * PAGE_SIZE, area->base,
pages*PAGE_SIZE)) {
pages * PAGE_SIZE)) {
if (b + c * PAGE_SIZE <= start_free) {
/*
553,7 → 557,7
if (area->backend &&
area->backend->frame_free) {
area->backend->frame_free(area, b +
j * PAGE_SIZE, PTE_GET_FRAME(pte));
j * PAGE_SIZE, PTE_GET_FRAME(pte));
}
page_mapping_remove(as, b + j * PAGE_SIZE);
page_table_unlock(as, false);
613,8 → 617,7
* 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. ENOTSUP is returned if the address space area backend does not support
* sharing or if the kernel detects an attempt to create an illegal address
* alias.
* sharing.
*/
int as_area_share(as_t *src_as, uintptr_t src_base, size_t acc_size,
as_t *dst_as, uintptr_t dst_base, int dst_flags_mask)
667,20 → 670,6
return EPERM;
}
 
#ifdef CONFIG_VIRT_IDX_DCACHE
if (!(dst_flags_mask & AS_AREA_EXEC)) {
if (PAGE_COLOR(src_area->base) != PAGE_COLOR(dst_base)) {
/*
* Refuse to create an illegal address alias.
*/
mutex_unlock(&src_area->lock);
mutex_unlock(&src_as->lock);
interrupts_restore(ipl);
return ENOTSUP;
}
}
#endif /* CONFIG_VIRT_IDX_DCACHE */
 
/*
* Now we are committed to sharing the area.
* First, prepare the area for sharing.
875,7 → 864,8
/** Switch address spaces.
*
* Note that this function cannot sleep as it is essentially a part of
* scheduling. Sleeping here would lead to deadlock on wakeup.
* scheduling. Sleeping here would lead to deadlock on wakeup. Another
* thing which is forbidden in this context is locking the address space.
*
* @param old Old address space or NULL.
* @param new New address space.
882,17 → 872,12
*/
void as_switch(as_t *old_as, as_t *new_as)
{
ipl_t ipl;
bool needs_asid = false;
ipl = interrupts_disable();
spinlock_lock(&inactive_as_with_asid_lock);
spinlock_lock(&asidlock);
 
/*
* First, take care of the old address space.
*/
if (old_as) {
mutex_lock_active(&old_as->lock);
ASSERT(old_as->cpu_refcount);
if((--old_as->cpu_refcount == 0) && (old_as != AS_KERNEL)) {
/*
901,11 → 886,10
* list of inactive address spaces with assigned
* ASID.
*/
ASSERT(old_as->asid != ASID_INVALID);
list_append(&old_as->inactive_as_with_asid_link,
&inactive_as_with_asid_head);
ASSERT(old_as->asid != ASID_INVALID);
list_append(&old_as->inactive_as_with_asid_link,
&inactive_as_with_asid_head);
}
mutex_unlock(&old_as->lock);
 
/*
* Perform architecture-specific tasks when the address space
917,36 → 901,15
/*
* Second, prepare the new address space.
*/
mutex_lock_active(&new_as->lock);
if ((new_as->cpu_refcount++ == 0) && (new_as != AS_KERNEL)) {
if (new_as->asid != ASID_INVALID) {
if (new_as->asid != ASID_INVALID)
list_remove(&new_as->inactive_as_with_asid_link);
} else {
/*
* Defer call to asid_get() until new_as->lock is released.
*/
needs_asid = true;
}
else
new_as->asid = asid_get();
}
#ifdef AS_PAGE_TABLE
SET_PTL0_ADDRESS(new_as->genarch.page_table);
#endif
mutex_unlock(&new_as->lock);
 
if (needs_asid) {
/*
* Allocation of new ASID was deferred
* until now in order to avoid deadlock.
*/
asid_t asid;
asid = asid_get();
mutex_lock_active(&new_as->lock);
new_as->asid = asid;
mutex_unlock(&new_as->lock);
}
spinlock_unlock(&inactive_as_with_asid_lock);
interrupts_restore(ipl);
/*
* Perform architecture-specific steps.
953,6 → 916,8
* (e.g. write ASID to hardware register etc.)
*/
as_install_arch(new_as);
 
spinlock_unlock(&asidlock);
AS = new_as;
}