Corrected an error where precious kernel virtual space was being allocated

for entire SYS5 SHM segments.  This is totally unnecessary, and so the
correct allocation of VM objects has been substituted.  (The vm_mmap
was misused -- vm_object_allocate is more appropriate.)

1 files changed, 21 insertions, 26 deletions

diff --git a/sys/kern/sysv_shm.c b/sys/kern/sysv_shm.c
index 5569f6d..e8e3ea2 100644
--- a/sys/kern/sysv_shm.c
+++ b/sys/kern/sysv_shm.c
@@ -1,4 +1,4 @@
-/*	$Id: sysv_shm.c,v 1.20 1996/05/03 21:01:24 phk Exp $ */
+/*	$Id: sysv_shm.c,v 1.21 1996/05/05 13:53:48 joerg Exp $ */
 /*	$NetBSD: sysv_shm.c,v 1.23 1994/07/04 23:25:12 glass Exp $	*/
 
 /*
@@ -49,6 +49,7 @@
 #include <vm/vm_prot.h>
 #include <vm/lock.h>
 #include <vm/pmap.h>
+#include <vm/vm_object.h>
 #include <vm/vm_map.h>
 #include <vm/vm_kern.h>
 #include <vm/vm_extern.h>
@@ -84,12 +85,12 @@ sy_call_t *shmcalls[] = {
 #define	SHMSEG_ALLOCATED	0x0800
 #define	SHMSEG_WANTED		0x1000
 
-static vm_map_t sysvshm_map;
 static int shm_last_free, shm_nused, shm_committed;
 struct shmid_ds	*shmsegs;
 
 struct shm_handle {
-	vm_offset_t kva;
+	/* vm_offset_t kva; */
+	vm_object_t shm_object;
 };
 
 struct shmmap_state {
@@ -141,10 +142,10 @@ shm_deallocate_segment(shmseg)
 	size_t size;
 
 	shm_handle = shmseg->shm_internal;
-	size = round_page(shmseg->shm_segsz);
-	(void) vm_map_remove(sysvshm_map, shm_handle->kva, shm_handle->kva + size);
+	vm_object_deallocate(shm_handle->shm_object);
 	free((caddr_t)shm_handle, M_SHM);
 	shmseg->shm_internal = NULL;
+	size = round_page(shmseg->shm_segsz);
 	shm_committed -= btoc(size);
 	shm_nused--;
 	shmseg->shm_perm.mode = SHMSEG_FREE;
@@ -220,9 +221,11 @@ shmat(p, uap, retval)
 	struct ucred *cred = p->p_ucred;
 	struct shmid_ds *shmseg;
 	struct shmmap_state *shmmap_s = NULL;
+	struct shm_handle *shm_handle;
 	vm_offset_t attach_va;
 	vm_prot_t prot;
 	vm_size_t size;
+	int rv;
 
 	shmmap_s = (struct shmmap_state *)p->p_vmspace->vm_shm;
 	if (shmmap_s == NULL) {
@@ -260,13 +263,17 @@ shmat(p, uap, retval)
 		else
 			return EINVAL;
 	} else {
-		/* This is just a hint to vm_mmap() about where to put it. */
+		/* This is just a hint to vm_map_find() about where to put it. */
 		attach_va = round_page(p->p_vmspace->vm_taddr + MAXTSIZ + MAXDSIZ);
 	}
-	error = vm_mmap(&p->p_vmspace->vm_map, &attach_va, size, prot,
-	    VM_PROT_DEFAULT, flags, (caddr_t) uap->shmid, 0);
-	if (error)
-		return error;
+
+	shm_handle = shmseg->shm_internal;
+	vm_object_reference(shm_handle->shm_object);
+	rv = vm_map_find(&p->p_vmspace->vm_map, shm_handle->shm_object,
+		0, &attach_va, size, (flags & MAP_FIXED)?0:1, prot, prot, 0);
+	if (rv != KERN_SUCCESS) {
+		return ENOMEM;
+	}
 	shmmap_s->va = attach_va;
 	shmmap_s->shmid = uap->shmid;
 	shmseg->shm_lpid = p->p_pid;
@@ -454,7 +461,7 @@ shmget_allocate_segment(p, uap, mode, retval)
 	int mode;
 	int *retval;
 {
-	int i, segnum, result, shmid, size;
+	int i, segnum, shmid, size;
 	struct ucred *cred = p->p_ucred;
 	struct shmid_ds *shmseg;
 	struct shm_handle *shm_handle;
@@ -488,16 +495,9 @@ shmget_allocate_segment(p, uap, mode, retval)
 	shm_handle = (struct shm_handle *)
 	    malloc(sizeof(struct shm_handle), M_SHM, M_WAITOK);
 	shmid = IXSEQ_TO_IPCID(segnum, shmseg->shm_perm);
-	result = vm_mmap(sysvshm_map, &shm_handle->kva, size, VM_PROT_ALL,
-	    VM_PROT_DEFAULT, MAP_ANON, (caddr_t) shmid, 0);
-	if (result != KERN_SUCCESS) {
-		shmseg->shm_perm.mode = SHMSEG_FREE;
-		shm_last_free = segnum;
-		free((caddr_t)shm_handle, M_SHM);
-		/* Just in case. */
-		wakeup((caddr_t)shmseg);
-		return ENOMEM;
-	}
+	
+	shm_handle->shm_object =
+		vm_object_allocate(OBJT_DEFAULT, round_page(size)/PAGE_SIZE);
 	shmseg->shm_internal = shm_handle;
 	shmseg->shm_perm.cuid = shmseg->shm_perm.uid = cred->cr_uid;
 	shmseg->shm_perm.cgid = shmseg->shm_perm.gid = cred->cr_gid;
@@ -601,11 +601,6 @@ shminit(dummy)
 	void *dummy;
 {
 	int i;
-	vm_offset_t garbage1, garbage2;
-
-	/* actually this *should* be pageable.  SHM_{LOCK,UNLOCK} */
-	sysvshm_map = kmem_suballoc(kernel_map, &garbage1, &garbage2,
-				    shminfo.shmall * PAGE_SIZE, TRUE);
 	for (i = 0; i < shminfo.shmmni; i++) {
 		shmsegs[i].shm_perm.mode = SHMSEG_FREE;
 		shmsegs[i].shm_perm.seq = 0;