[src/trunk]: src/sys/kern Align parsing of boot devices. This allows to speci...

[mlelstv <mlelstv%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/127057d26efe
branches:  trunk
changeset: 453561:127057d26efe
user:      mlelstv <mlelstv%NetBSD.org@localhost>
date:      Sun Aug 18 06:28:42 2019 +0000

description:
Align parsing of boot devices. This allows to specify device names
as strings in the boot loader and the kernel configuration.

diffstat:

 sys/kern/kern_subr.c |  81 ++++++++++++++++++++++++++++-----------------------
 1 files changed, 45 insertions(+), 36 deletions(-)

diffs (174 lines):

diff -r 56bfabf18474 -r 127057d26efe sys/kern/kern_subr.c
--- a/sys/kern/kern_subr.c      Sun Aug 18 04:14:40 2019 +0000
+++ b/sys/kern/kern_subr.c      Sun Aug 18 06:28:42 2019 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: kern_subr.c,v 1.223 2019/01/27 02:08:43 pgoyette Exp $ */
+/*     $NetBSD: kern_subr.c,v 1.224 2019/08/18 06:28:42 mlelstv Exp $  */
 
 /*-
  * Copyright (c) 1997, 1998, 1999, 2002, 2007, 2008 The NetBSD Foundation, Inc.
@@ -79,7 +79,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_subr.c,v 1.223 2019/01/27 02:08:43 pgoyette Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_subr.c,v 1.224 2019/08/18 06:28:42 mlelstv Exp $");
 
 #include "opt_ddb.h"
 #include "opt_md.h"
@@ -107,8 +107,8 @@
 
 /* XXX these should eventually move to subr_autoconf.c */
 static device_t finddevice(const char *);
-static device_t getdisk(char *, int, int, dev_t *, int);
-static device_t parsedisk(char *, int, int, dev_t *);
+static device_t getdisk(const char *, int, int, dev_t *, int);
+static device_t parsedisk(const char *, int, int, dev_t *);
 static const char *getwedgename(const char *, int);
 
 static void setroot_nfs(device_t);
@@ -185,10 +185,13 @@
 {
 
        /*
-        * Let bootcode augment "rootspec".
+        * Let bootcode augment "rootspec", ensure that
+        * rootdev is invalid to avoid confusion.
         */
-       if (rootspec == NULL)
+       if (rootspec == NULL) {
                rootspec = bootspec;
+               rootdev = NODEV;
+       }
 
        /*
         * force boot device to md0
@@ -448,9 +451,9 @@
 
 /*
  * configure
- *   dev_t rootdev
+ *   device_t root_device
+ *   dev_t rootdev (for disks)
  * 
- * return device_t or NULL if not found
  */
 static void
 setroot_root(device_t bootdv, int bootpartition)
@@ -459,6 +462,7 @@
        int majdev;
        const char *rootdevname;
        char buf[128];
+       dev_t nrootdev;
 
        if (rootspec == NULL) {
 
@@ -490,20 +494,17 @@
                 */
 
                /*
-                * If it's a network interface, we can bail out
-                * early.
+                * If rootspec can be parsed, just use it.
                 */
-               rootdv = finddevice(rootspec);
-               if (rootdv != NULL && device_class(rootdv) == DV_IFNET)
-                       goto haveroot;
-
-               if (rootdv != NULL && device_class(rootdv) == DV_DISK &&
-                   !DEV_USES_PARTITIONS(rootdv) &&
-                   (majdev = devsw_name2blk(device_xname(rootdv), NULL, 0)) >= 0) {
-                       rootdev = makedev(majdev, device_unit(rootdv));
+               rootdv = parsedisk(rootspec, strlen(rootspec), 0, &nrootdev);
+               if (rootdv != NULL) {
+                       rootdev = nrootdev;
                        goto haveroot;
                }
 
+               /*
+                * Fall back to rootdev, compute rootdv for it
+                */
                rootdevname = devsw_blk2name(major(rootdev));
                if (rootdevname == NULL) {
                        printf("unknown device major 0x%llx\n",
@@ -647,11 +648,22 @@
 }
 
 static device_t
-getdisk(char *str, int len, int defpart, dev_t *devp, int isdump)
+getdisk(const char *str, int len, int defpart, dev_t *devp, int isdump)
 {
        device_t dv;
        deviter_t di;
 
+       if (len == 4 && strcmp(str, "halt") == 0)
+               cpu_reboot(RB_HALT, NULL);
+       else if (len == 6 && strcmp(str, "reboot") == 0)
+               cpu_reboot(0, NULL);
+#if defined(DDB)
+       else if (len == 3 && strcmp(str, "ddb") == 0) {
+               console_debugger();
+               return NULL;
+       }
+#endif
+
        if ((dv = parsedisk(str, len, defpart, devp)) == NULL) {
                printf("use one of:");
                for (dv = deviter_first(&di, DEVITER_F_ROOT_FIRST); dv != NULL;
@@ -689,35 +701,33 @@
 }
 
 static device_t
-parsedisk(char *str, int len, int defpart, dev_t *devp)
+parsedisk(const char *str, int len, int defpart, dev_t *devp)
 {
        device_t dv;
        const char *wname;
-       char *cp, c;
+       char c;
        int majdev, part;
+       char xname[16]; /* same size as dv_xname */
+
        if (len == 0)
                return (NULL);
 
-       if (len == 4 && strcmp(str, "halt") == 0)
-               cpu_reboot(RB_HALT, NULL);
-       else if (len == 6 && strcmp(str, "reboot") == 0)
-               cpu_reboot(0, NULL);
-#if defined(DDB)
-       else if (len == 3 && strcmp(str, "ddb") == 0)
-               console_debugger();
-#endif
-
-       cp = str + len - 1;
-       c = *cp;
-
        if ((wname = getwedgename(str, len)) != NULL) {
                if ((dv = dkwedge_find_by_wname(wname)) == NULL)
                        return NULL;
                part = defpart;
                goto gotdisk;
-       } else if (c >= 'a' && c <= ('a' + MAXPARTITIONS - 1)) {
+       }
+
+       c = str[len-1];
+       if (c >= 'a' && c <= ('a' + MAXPARTITIONS - 1)) {
                part = c - 'a';
-               *cp = '\0';
+               len--;
+               if (len > sizeof(xname)-1)
+                       return NULL;
+               memcpy(xname, str, len);
+               xname[len] = '\0';
+               str = xname;
        } else
                part = defpart;
 
@@ -739,6 +749,5 @@
                        *devp = NODEV;
        }
 
-       *cp = c;
        return (dv);
 }