MFC r258056 (by alc):

Eliminate the gratuitous use of mmap(2) flags from the implementation
of kern_shmat().  Use a simpler approach to determine whether to pass
VMFS_NO_SPACE or VMFS_OPTIMAL_SPACE to vm_map_find().
This commit is contained in:
kib 2015-04-04 07:52:12 +00:00
parent 44dfc90bcd
commit 7b4777f74a

View File

@ -342,7 +342,7 @@ kern_shmat(td, shmid, shmaddr, shmflg)
int shmflg;
{
struct proc *p = td->td_proc;
int i, flags;
int i;
struct shmid_kernel *shmseg;
struct shmmap_state *shmmap_s = NULL;
vm_offset_t attach_va;
@ -402,9 +402,7 @@ kern_shmat(td, shmid, shmaddr, shmflg)
prot = VM_PROT_READ;
if ((shmflg & SHM_RDONLY) == 0)
prot |= VM_PROT_WRITE;
flags = MAP_ANON | MAP_SHARED;
if (shmaddr) {
flags |= MAP_FIXED;
if (shmflg & SHM_RND) {
attach_va = (vm_offset_t)shmaddr & ~(SHMLBA-1);
} else if (((vm_offset_t)shmaddr & (SHMLBA-1)) == 0) {
@ -426,7 +424,7 @@ kern_shmat(td, shmid, shmaddr, shmflg)
vm_object_reference(shmseg->object);
rv = vm_map_find(&p->p_vmspace->vm_map, shmseg->object,
0, &attach_va, size, 0, (flags & MAP_FIXED) ? VMFS_NO_SPACE :
0, &attach_va, size, 0, shmaddr != NULL ? VMFS_NO_SPACE :
VMFS_OPTIMAL_SPACE, prot, prot, MAP_INHERIT_SHARE);
if (rv != KERN_SUCCESS) {
vm_object_deallocate(shmseg->object);