kboot: Add support for ZFS volumes

[imp]

Summary

Add the zfs device and filesystem to config and write the hook we need
to probe zfs since there's not a generic mechanism in place to do that
when ZFS is configured.

Sponsored by: Netflix

[imp]

rebase / ping

stand/kboot/conf.c

 __FBSDID("$FreeBSD$");
 
 #include <stand.h>
 #include "bootstrap.h"
 
 #if defined(LOADER_NET_SUPPORT)
 #include "dev_net.h"
 #endif
+#ifdef LOADER_ZFS_SUPPORT
+#include "libzfs.h"
+#endif
 
 extern struct devsw hostdisk;
 extern struct devsw host_dev;
 
 /*
  * We could use linker sets for some or all of these, but
  * then we would have to control what ended up linked into
  * the bootstrap.  So it's easier to conditionalise things
  * here.
  *
  * XXX rename these arrays to be consistent and less namespace-hostile
  */
 
 /* Exported for libsa */
 struct devsw *devsw[] = {
 #if defined(LOADER_DISK_SUPPORT) || defined(LOADER_CD9660_SUPPORT)
     &hostdisk,
 #endif
 #if defined(LOADER_NET_SUPPORT)
     &netdev,
 #endif
     &host_dev,
+#if defined(LOADER_ZFS_SUPPORT)
+    &zfs_dev,                               /* Must be last */
+#endif
     NULL
 };
 
 extern struct fs_ops hostfs_fsops;
 
 struct fs_ops *file_system[] = {
 #if defined(LOADER_UFS_SUPPORT)
     &ufs_fsops,

 #if defined(LOADER_GZIP_SUPPORT)
     &gzipfs_fsops,
 #endif
 #if defined(LOADER_BZIP2_SUPPORT)
     &bzipfs_fsops,
 #endif
 #if defined(LOADER_MSDOS_SUPPORT)
     &dosfs_fsops,
+#endif
+#if defined(LOADER_ZFS_SUPPORT)
+        &zfs_fsops,
 #endif
     &hostfs_fsops,
     NULL
 };
 
 extern struct netif_driver kbootnet;
 
 struct netif_driver *netif_drivers[] = {

stand/kboot/main.c

 
 int kboot_getdev(void **vdev, const char *devspec, const char **path);
 ssize_t kboot_copyin(const void *src, vm_offset_t dest, const size_t len);
 ssize_t kboot_copyout(vm_offset_t src, void *dest, const size_t len);
 ssize_t kboot_readin(readin_handle_t fd, vm_offset_t dest, const size_t len);
 int kboot_autoload(void);
 uint64_t kboot_loadaddr(u_int type, void *data, uint64_t addr);
 static void kboot_kseg_get(int *nseg, void **ptr);
+static void kboot_zfs_probe(void);
 
 extern int command_fdt_internal(int argc, char *argv[]);
 
 /*
  * NB: getdev should likely be identical to this most places, except maybe
  * we should move to storing the length of the platform devdesc.
  */
 int
main(int argc, const char **argv)
 
         archsw.arch_getdev = kboot_getdev;
         archsw.arch_copyin = kboot_copyin;
         archsw.arch_copyout = kboot_copyout;
         archsw.arch_readin = kboot_readin;
         archsw.arch_autoload = kboot_autoload;
         archsw.arch_loadaddr = kboot_loadaddr;
         archsw.arch_kexec_kseg_get = kboot_kseg_get;
+        archsw.arch_zfs_probe = kboot_zfs_probe;
 
         /* Give us a sane world if we're running as init */
         do_init();
 
         /*
          * Setup the heap 15MB should be plenty
          */
         heapbase = host_getmem(heapsize);
printf("kseg_get: %jx %jx %jx %jx\n",
                         (uintmax_t)loaded_segments[a].bufsz,
                         (uintmax_t)loaded_segments[a].mem,
                         (uintmax_t)loaded_segments[a].memsz);
         }
 #endif
 
         *nseg = nkexec_segments;
         *ptr = &loaded_segments[0];
+}
+
+static void
+kboot_zfs_probe(void)
+{
+#if defined(LOADER_ZFS_SUPPORT)
+        /*
+         * Open all the disks and partitions we can find to see if there are ZFS
+         * pools on them.
+         */
+        hostdisk_zfs_probe();
+#endif
 }
 
 /*
  * Since proper fdt command handling function is defined in fdt_loader_cmd.c,
  * and declaring it as extern is in contradiction with COMMAND_SET() macro
  * (which uses static pointer), we're defining wrapper function, which
  * calls the proper fdt handling routine.
  */
 static int
 command_fdt(int argc, char *argv[])
 {
 
         return (command_fdt_internal(argc, argv));
 }
         
 COMMAND_SET(fdt, "fdt", "flattened device tree handling", command_fdt);