Dissociate ptrace from procfs.

Until now, the ptrace syscall was implemented as a wrapper that called
various functions in procfs depending on which ptrace operation was
requested.  Most of these functions were themselves wrappers around
procfs_{read,write}_{,db,fp}regs(), with only some extra error checks,
which weren't necessary in the ptrace case anyway.

This commit moves procfs_rwmem() from procfs_mem.c into sys_process.c
(renaming it to proc_rwmem() in the process), and implements ptrace()
directly in terms of procfs_{read,write}_{,db,fp}regs() instead of
having it fake up a struct uio and then call procfs_do{,db,fp}regs().

It also moves the prototypes for procfs_{read,write}_{,db,fp}regs()
and proc_rwmem() from proc.h to ptrace.h, and marks all procfs files
except procfs_machdep.c as "optional procfs" instead of "standard".

5 files changed, 4 insertions, 226 deletions

diff --git a/sys/fs/procfs/procfs.h b/sys/fs/procfs/procfs.h
index d97f825..67af4be 100644
--- a/sys/fs/procfs/procfs.h
+++ b/sys/fs/procfs/procfs.h
@@ -118,15 +118,6 @@ struct dbreg;
 void procfs_exit __P((struct proc *));
 int procfs_freevp __P((struct vnode *));
 int procfs_allocvp __P((struct mount *, struct vnode **, long, pfstype));
-struct vnode *procfs_findtextvp __P((struct proc *));
-int procfs_sstep __P((struct thread *));
-void procfs_fix_sstep __P((struct thread *));
-int procfs_read_regs __P((struct thread *, struct reg *));
-int procfs_write_regs __P((struct thread *, struct reg *));
-int procfs_read_fpregs __P((struct thread *, struct fpreg *));
-int procfs_write_fpregs __P((struct thread *, struct fpreg *));
-int procfs_read_dbregs __P((struct thread *, struct dbreg *));
-int procfs_write_dbregs __P((struct thread *, struct dbreg *));
 int procfs_donote __P((struct proc *, struct proc *, struct pfsnode *pfsp, struct uio *uio));
 int procfs_doregs __P((struct proc *, struct proc *, struct pfsnode *pfsp, struct uio *uio));
 int procfs_dofpregs __P((struct proc *, struct proc *, struct pfsnode *pfsp, struct uio *uio));
diff --git a/sys/fs/procfs/procfs_dbregs.c b/sys/fs/procfs/procfs_dbregs.c
index 5de041a..1327f27 100644
--- a/sys/fs/procfs/procfs_dbregs.c
+++ b/sys/fs/procfs/procfs_dbregs.c
@@ -48,6 +48,7 @@
 #include <sys/lock.h>
 #include <sys/mutex.h>
 #include <sys/proc.h>
+#include <sys/ptrace.h>
 #include <sys/vnode.h>
 
 #include <machine/reg.h>
diff --git a/sys/fs/procfs/procfs_fpregs.c b/sys/fs/procfs/procfs_fpregs.c
index 2b68693..b01509b 100644
--- a/sys/fs/procfs/procfs_fpregs.c
+++ b/sys/fs/procfs/procfs_fpregs.c
@@ -45,6 +45,7 @@
 #include <sys/lock.h>
 #include <sys/mutex.h>
 #include <sys/proc.h>
+#include <sys/ptrace.h>
 #include <sys/vnode.h>
 
 #include <machine/reg.h>
diff --git a/sys/fs/procfs/procfs_mem.c b/sys/fs/procfs/procfs_mem.c
index 29773a0..95c91f2 100644
--- a/sys/fs/procfs/procfs_mem.c
+++ b/sys/fs/procfs/procfs_mem.c
@@ -40,11 +40,6 @@
  * $FreeBSD$
  */
 
-/*
- * This is a lightly hacked and merged version
- * of sef's pread/pwrite functions
- */
-
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/lock.h>
@@ -56,184 +51,6 @@
 
 #include <fs/procfs/procfs.h>
 
-#include <vm/vm.h>
-#include <vm/vm_param.h>
-#include <vm/pmap.h>
-#include <vm/vm_extern.h>
-#include <vm/vm_map.h>
-#include <vm/vm_kern.h>
-#include <vm/vm_object.h>
-#include <vm/vm_page.h>
-
-static int	procfs_rwmem __P((struct proc *curp,
-				  struct proc *p, struct uio *uio));
-
-static int
-procfs_rwmem(curp, p, uio)
-	struct proc *curp;
-	struct proc *p;
-	struct uio *uio;
-{
-	int error;
-	int writing;
-	struct vmspace *vm;
-	vm_map_t map;
-	vm_object_t object = NULL;
-	vm_offset_t pageno = 0;		/* page number */
-	vm_prot_t reqprot;
-	vm_offset_t kva;
-
-	GIANT_REQUIRED;
-
-	/*
-	 * if the vmspace is in the midst of being deallocated or the
-	 * process is exiting, don't try to grab anything.  The page table
-	 * usage in that process can be messed up.
-	 */
-	vm = p->p_vmspace;
-	if ((p->p_flag & P_WEXIT))
-		return EFAULT;
-	if (vm->vm_refcnt < 1)
-		return EFAULT;
-	++vm->vm_refcnt;
-	/*
-	 * The map we want...
-	 */
-	map = &vm->vm_map;
-
-	writing = uio->uio_rw == UIO_WRITE;
-	reqprot = writing ? (VM_PROT_WRITE | VM_PROT_OVERRIDE_WRITE) : VM_PROT_READ;
-
-	kva = kmem_alloc_pageable(kernel_map, PAGE_SIZE);
-
-	/*
-	 * Only map in one page at a time.  We don't have to, but it
-	 * makes things easier.  This way is trivial - right?
-	 */
-	do {
-		vm_map_t tmap;
-		vm_offset_t uva;
-		int page_offset;		/* offset into page */
-		vm_map_entry_t out_entry;
-		vm_prot_t out_prot;
-		boolean_t wired;
-		vm_pindex_t pindex;
-		u_int len;
-		vm_page_t m;
-
-		object = NULL;
-
-		uva = (vm_offset_t) uio->uio_offset;
-
-		/*
-		 * Get the page number of this segment.
-		 */
-		pageno = trunc_page(uva);
-		page_offset = uva - pageno;
-
-		/*
-		 * How many bytes to copy
-		 */
-		len = min(PAGE_SIZE - page_offset, uio->uio_resid);
-
-		/*
-		 * Fault the page on behalf of the process
-		 */
-		error = vm_fault(map, pageno, reqprot, VM_FAULT_NORMAL);
-		if (error) {
-			error = EFAULT;
-			break;
-		}
-
-		/*
-		 * Now we need to get the page.  out_entry, out_prot, wired,
-		 * and single_use aren't used.  One would think the vm code
-		 * would be a *bit* nicer...  We use tmap because
-		 * vm_map_lookup() can change the map argument.
-		 */
-		tmap = map;
-		error = vm_map_lookup(&tmap, pageno, reqprot,
-			      &out_entry, &object, &pindex, &out_prot,
-			      &wired);
-
-		if (error) {
-			error = EFAULT;
-
-			/*
-			 * Make sure that there is no residue in 'object' from
-			 * an error return on vm_map_lookup.
-			 */
-			object = NULL;
-
-			break;
-		}
-
-		m = vm_page_lookup(object, pindex);
-
-		/* Allow fallback to backing objects if we are reading */
-
-		while (m == NULL && !writing && object->backing_object) {
-
-		  pindex += OFF_TO_IDX(object->backing_object_offset);
-		  object = object->backing_object;
-
-		  m = vm_page_lookup(object, pindex);
-		}
-
-		if (m == NULL) {
-			error = EFAULT;
-
-			/*
-			 * Make sure that there is no residue in 'object' from
-			 * an error return on vm_map_lookup.
-			 */
-			object = NULL;
-
-			vm_map_lookup_done(tmap, out_entry);
-
-			break;
-		}
-
-		/*
-		 * Wire the page into memory
-		 */
-		vm_page_wire(m);
-
-		/*
-		 * We're done with tmap now.
-		 * But reference the object first, so that we won't loose
-		 * it.
-		 */
-		vm_object_reference(object);
-		vm_map_lookup_done(tmap, out_entry);
-
-		pmap_kenter(kva, VM_PAGE_TO_PHYS(m));
-
-		/*
-		 * Now do the i/o move.
-		 */
-		error = uiomove((caddr_t)(kva + page_offset), len, uio);
-
-		pmap_kremove(kva);
-
-		/*
-		 * release the page and the object
-		 */
-		vm_page_unwire(m, 1);
-		vm_object_deallocate(object);
-
-		object = NULL;
-
-	} while (error == 0 && uio->uio_resid > 0);
-
-	if (object)
-		vm_object_deallocate(object);
-
-	kmem_free(kernel_map, kva, PAGE_SIZE);
-	vmspace_free(vm);
-	return (error);
-}
-
 /*
  * Copy data in and out of the target process.
  * We do this by mapping the process's page into
@@ -256,38 +73,5 @@ procfs_domem(curp, p, pfs, uio)
 	if (error)
 		return (error);
 
-	return (procfs_rwmem(curp, p, uio));
-}
-
-/*
- * Given process (p), find the vnode from which
- * its text segment is being executed.
- *
- * It would be nice to grab this information from
- * the VM system, however, there is no sure-fire
- * way of doing that.  Instead, fork(), exec() and
- * wait() all maintain the p_textvp field in the
- * process proc structure which contains a held
- * reference to the exec'ed vnode.
- *
- * XXX - Currently, this is not not used, as the
- * /proc/pid/file object exposes an information leak
- * that shouldn't happen.  Using a mount option would
- * make it configurable on a per-system (or, at least,
- * per-mount) basis; however, that's not really best.
- * The best way to do it, I think, would be as an
- * ioctl; this would restrict it to the uid running
- * program, or root, which seems a reasonable compromise.
- * However, the number of applications for this is
- * minimal, if it can't be seen in the filesytem space,
- * and doint it as an ioctl makes it somewhat less
- * useful due to the, well, inelegance.
- *
- */
-struct vnode *
-procfs_findtextvp(p)
-	struct proc *p;
-{
-
-	return (p->p_textvp);
+	return (proc_rwmem(p, uio));
 }
diff --git a/sys/fs/procfs/procfs_regs.c b/sys/fs/procfs/procfs_regs.c
index f590075..27e950d 100644
--- a/sys/fs/procfs/procfs_regs.c
+++ b/sys/fs/procfs/procfs_regs.c
@@ -45,6 +45,7 @@
 #include <sys/lock.h>
 #include <sys/mutex.h>
 #include <sys/proc.h>
+#include <sys/ptrace.h>
 #include <sys/vnode.h>
 
 #include <machine/reg.h>