Improve abstraction. Eliminate direct access by elf*_load_section()

to an OBJT_VNODE-specific field of the vm object.  The same
information can be just as easily obtained from the struct vattr that
is in struct image_params if the latter is passed to
elf*_load_section().  Moreover, by replacing the vmspace and vm
object parameters to elf*_load_section() with a struct image_params
parameter, we actually reduce the size of the object code.

In collaboration with:	kib

1 files changed, 25 insertions, 26 deletions

diff --git a/sys/kern/imgact_elf.c b/sys/kern/imgact_elf.c
index 9794544..f7e5752 100644
--- a/sys/kern/imgact_elf.c
+++ b/sys/kern/imgact_elf.c
@@ -86,9 +86,9 @@ static Elf_Brandinfo *__elfN(get_brandinfo)(struct image_params *imgp,
     const char *interp, int32_t *osrel);
 static int __elfN(load_file)(struct proc *p, const char *file, u_long *addr,
     u_long *entry, size_t pagesize);
-static int __elfN(load_section)(struct vmspace *vmspace, vm_object_t object,
-    vm_offset_t offset, caddr_t vmaddr, size_t memsz, size_t filsz,
-    vm_prot_t prot, size_t pagesize);
+static int __elfN(load_section)(struct image_params *imgp, vm_offset_t offset,
+    caddr_t vmaddr, size_t memsz, size_t filsz, vm_prot_t prot,
+    size_t pagesize);
 static int __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp);
 static boolean_t __elfN(freebsd_trans_osrel)(const Elf_Note *note,
     int32_t *osrel);
@@ -445,13 +445,14 @@ __elfN(map_insert)(vm_map_t map, vm_object_t object, vm_ooffset_t offset,
 }
 
 static int
-__elfN(load_section)(struct vmspace *vmspace,
-	vm_object_t object, vm_offset_t offset,
-	caddr_t vmaddr, size_t memsz, size_t filsz, vm_prot_t prot,
-	size_t pagesize)
+__elfN(load_section)(struct image_params *imgp, vm_offset_t offset,
+    caddr_t vmaddr, size_t memsz, size_t filsz, vm_prot_t prot,
+    size_t pagesize)
 {
 	struct sf_buf *sf;
 	size_t map_len;
+	vm_map_t map;
+	vm_object_t object;
 	vm_offset_t map_addr;
 	int error, rv, cow;
 	size_t copy_len;
@@ -466,12 +467,13 @@ __elfN(load_section)(struct vmspace *vmspace,
 	 * While I'm here, might as well check for something else that
 	 * is invalid: filsz cannot be greater than memsz.
 	 */
-	if ((off_t)filsz + offset > object->un_pager.vnp.vnp_size ||
-	    filsz > memsz) {
+	if ((off_t)filsz + offset > imgp->attr->va_size || filsz > memsz) {
 		uprintf("elf_load_section: truncated ELF file\n");
 		return (ENOEXEC);
 	}
 
+	object = imgp->object;
+	map = &imgp->proc->p_vmspace->vm_map;
 	map_addr = trunc_page_ps((vm_offset_t)vmaddr, pagesize);
 	file_addr = trunc_page_ps(offset, pagesize);
 
@@ -491,7 +493,7 @@ __elfN(load_section)(struct vmspace *vmspace,
 		cow = MAP_COPY_ON_WRITE | MAP_PREFAULT |
 		    (prot & VM_PROT_WRITE ? 0 : MAP_DISABLE_COREDUMP);
 
-		rv = __elfN(map_insert)(&vmspace->vm_map,
+		rv = __elfN(map_insert)(map,
 				      object,
 				      file_addr,	/* file offset */
 				      map_addr,		/* virtual start */
@@ -521,8 +523,8 @@ __elfN(load_section)(struct vmspace *vmspace,
 
 	/* This had damn well better be true! */
 	if (map_len != 0) {
-		rv = __elfN(map_insert)(&vmspace->vm_map, NULL, 0, map_addr,
-		    map_addr + map_len, VM_PROT_ALL, 0);
+		rv = __elfN(map_insert)(map, NULL, 0, map_addr, map_addr +
+		    map_len, VM_PROT_ALL, 0);
 		if (rv != KERN_SUCCESS) {
 			return (EINVAL);
 		}
@@ -550,8 +552,8 @@ __elfN(load_section)(struct vmspace *vmspace,
 	 * set it to the specified protection.
 	 * XXX had better undo the damage from pasting over the cracks here!
 	 */
-	vm_map_protect(&vmspace->vm_map, trunc_page(map_addr),
-	    round_page(map_addr + map_len),  prot, FALSE);
+	vm_map_protect(map, trunc_page(map_addr), round_page(map_addr +
+	    map_len), prot, FALSE);
 
 	return (0);
 }
@@ -580,7 +582,6 @@ __elfN(load_file)(struct proc *p, const char *file, u_long *addr,
 	const Elf_Ehdr *hdr = NULL;
 	const Elf_Phdr *phdr = NULL;
 	struct nameidata *nd;
-	struct vmspace *vmspace = p->p_vmspace;
 	struct vattr *attr;
 	struct image_params *imgp;
 	vm_prot_t prot;
@@ -672,11 +673,10 @@ __elfN(load_file)(struct proc *p, const char *file, u_long *addr,
 		if (phdr[i].p_type == PT_LOAD && phdr[i].p_memsz != 0) {
 			/* Loadable segment */
 			prot = __elfN(trans_prot)(phdr[i].p_flags);
-			if ((error = __elfN(load_section)(vmspace,
-			    imgp->object, phdr[i].p_offset,
+			error = __elfN(load_section)(imgp, phdr[i].p_offset,
 			    (caddr_t)(uintptr_t)phdr[i].p_vaddr + rbase,
-			    phdr[i].p_memsz, phdr[i].p_filesz, prot,
-			    pagesize)) != 0)
+			    phdr[i].p_memsz, phdr[i].p_filesz, prot, pagesize);
+			if (error != 0)
 				goto fail;
 			/*
 			 * Establish the base address if this is the
@@ -810,8 +810,6 @@ __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp)
 	if (error)
 		return (error);
 
-	vmspace = imgp->proc->p_vmspace;
-
 	for (i = 0; i < hdr->e_phnum; i++) {
 		switch (phdr[i].p_type) {
 		case PT_LOAD:	/* Loadable segment */
@@ -828,11 +826,11 @@ __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp)
 				prot |= VM_PROT_EXECUTE;
 #endif
 
-			if ((error = __elfN(load_section)(vmspace,
-			    imgp->object, phdr[i].p_offset,
+			error = __elfN(load_section)(imgp, phdr[i].p_offset,
 			    (caddr_t)(uintptr_t)phdr[i].p_vaddr + et_dyn_addr,
 			    phdr[i].p_memsz, phdr[i].p_filesz, prot,
-			    sv->sv_pagesize)) != 0)
+			    sv->sv_pagesize);
+			if (error != 0)
 				return (error);
 
 			/*
@@ -901,6 +899,7 @@ __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp)
 		return (ENOMEM);
 	}
 
+	vmspace = imgp->proc->p_vmspace;
 	vmspace->vm_tsize = text_size >> PAGE_SHIFT;
 	vmspace->vm_taddr = (caddr_t)(uintptr_t)text_addr;
 	vmspace->vm_dsize = data_size >> PAGE_SHIFT;
@@ -912,8 +911,8 @@ __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp)
 	 * calculation is that it leaves room for the heap to grow to
 	 * its maximum allowed size.
 	 */
-	addr = round_page((vm_offset_t)imgp->proc->p_vmspace->vm_daddr +
-	    lim_max(imgp->proc, RLIMIT_DATA));
+	addr = round_page((vm_offset_t)vmspace->vm_daddr + lim_max(imgp->proc,
+	    RLIMIT_DATA));
 	PROC_UNLOCK(imgp->proc);
 
 	imgp->entry_addr = entry;