file-systems: Remove 'title' field and add <file-system-label>.

The 'title' field was easily overlooked and was an endless source of
confusion.  Now, the value of the 'device' field is self-contained.

* gnu/system/file-systems.scm (<file-system>): Change constructor name
to '%file-system'.
[title]: Remove.
(<file-system-label>): New record type with printer.
(report-deprecation, device-expression)
(process-file-system-declaration, file-system): New macros.
(file-system-title): New procedure.
(file-system->spec, spec->file-system): Adjust to handle
<file-system-label>.
* gnu/system.scm (bootable-kernel-arguments): Add case for
'file-system-label?'.
(read-boot-parameters): Likewise.
(mapped-device-user): Avoid 'file-system-title'.
(fs->boot-device): Remove.
(operating-system-boot-parameters): Use 'file-system-device' instead of
'fs->boot-device'.
(device->sexp): Add case for 'file-system-label?'.
* gnu/bootloader/grub.scm (grub-root-search): Add case for
'file-system-label?'.
* gnu/system/examples/bare-bones.tmpl,
gnu/system/examples/beaglebone-black.tmpl,
gnu/system/examples/lightweight-desktop.tmpl,
gnu/system/examples/vm-image.tmpl: Remove uses of 'title'.
* gnu/system/vm.scm (virtualized-operating-system): Remove uses of
'file-system-title'.
* guix/scripts/system.scm (check-file-system-availability): Likewise,
and adjust fix-it hint.
(check-initrd-modules)[file-system-/dev]: Likewise.
* gnu/build/file-systems.scm (canonicalize-device-spec): Remove 'title'
parameter.
[canonical-title]: Remove.
Match on SPEC's type rather than on CANONICAL-TITLE.
(mount-file-system): Adjust caller.
* gnu/build/linux-boot.scm (boot-system): Interpret ROOT here.
* gnu/services/base.scm (file-system->fstab-entry): Remove use of
'file-system-title'.
* doc/guix.texi (File Systems): Remove documentation of the 'title'
field.  Rewrite documentation of 'device' and document
'file-system-label'.

1 files changed, 17 insertions, 14 deletions

diff --git a/guix/scripts/system.scm b/guix/scripts/system.scm
index af501eb8f7..5d0df14924 100644
--- a/guix/scripts/system.scm
+++ b/guix/scripts/system.scm
@@ -590,17 +590,17 @@ any, are available.  Raise an error if they're not."
 
   (define labeled
     (filter (lambda (fs)
-              (eq? (file-system-title fs) 'label))
+              (file-system-label? (file-system-device fs)))
             relevant))
 
   (define literal
     (filter (lambda (fs)
-              (eq? (file-system-title fs) 'device))
+              (string? (file-system-device fs)))
             relevant))
 
   (define uuid
     (filter (lambda (fs)
-              (eq? (file-system-title fs) 'uuid))
+              (uuid? (file-system-device fs)))
             relevant))
 
   (define fail? #f)
@@ -628,15 +628,15 @@ any, are available.  Raise an error if they're not."
                              (strerror errno))
                       (unless (string-prefix? "/" device)
                         (display-hint (format #f (G_ "If '~a' is a file system
-label, you need to add @code{(title 'label)} to your @code{file-system}
-definition.")
-                                              device)))))))
+label, write @code{(file-system-label ~s)} in your @code{device} field.")
+                                              device device)))))))
               literal)
     (for-each (lambda (fs)
-                (unless (find-partition-by-label (file-system-device fs))
-                  (error (G_ "~a: error: file system with label '~a' not found~%")
-                         (file-system-location* fs)
-                         (file-system-device fs))))
+                (let ((label (file-system-label->string
+                              (file-system-device fs))))
+                  (unless (find-partition-by-label label)
+                    (error (G_ "~a: error: file system with label '~a' not found~%")
+                           (file-system-location* fs) label))))
               labeled)
     (for-each (lambda (fs)
                 (unless (find-partition-by-uuid (file-system-device fs))
@@ -677,10 +677,13 @@ available in the initrd.  Note that mapped devices are responsible for
 checking this by themselves in their 'check' procedure."
   (define (file-system-/dev fs)
     (let ((device (file-system-device fs)))
-      (match (file-system-title fs)
-        ('device device)
-        ('uuid   (find-partition-by-uuid device))
-        ('label  (find-partition-by-label device)))))
+      (match device
+        ((? string?)
+         device)
+        ((? uuid?)
+         (find-partition-by-uuid device))
+        ((? file-system-label?)
+         (find-partition-by-label (file-system-label->string device))))))
 
   (define file-systems
     (filter file-system-needed-for-boot?