From: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
To: linuxppc-dev@ozlabs.org, thuth@redhat.com, segher@kernel.crashing.org
Cc: aik@ozlabs.ru, dvaleev@suse.com, nikunj@linux.vnet.ibm.com
Subject: [PATCH SLOF v3 4/5] disk-label: introduce helper to check fat filesystem
Date: Tue, 30 Jun 2015 16:31:20 +0530 [thread overview]
Message-ID: <1435662081-4293-5-git-send-email-nikunj@linux.vnet.ibm.com> (raw)
In-Reply-To: <1435662081-4293-1-git-send-email-nikunj@linux.vnet.ibm.com>
Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
---
slof/fs/packages/disk-label.fs | 17 +++++++++--------
1 file changed, 9 insertions(+), 8 deletions(-)
diff --git a/slof/fs/packages/disk-label.fs b/slof/fs/packages/disk-label.fs
index e5a0546..347dc5d 100644
--- a/slof/fs/packages/disk-label.fs
+++ b/slof/fs/packages/disk-label.fs
@@ -321,6 +321,14 @@ CONSTANT /gpt-part-entry
\ Load from first active DOS boot partition.
+: fat-bootblock? ( addr -- flag )
+ \ byte 0-2 of the bootblock is a jump instruction in
+ \ all FAT filesystems.
+ \ e9 and eb are jump instructions in x86 assembler.
+ dup c@ e9 = IF drop true EXIT THEN
+ dup c@ eb = swap 2+ c@ 90 = and
+;
+
\ NOTE: block-size is always 512 bytes for DOS partition tables.
: load-from-dos-boot-partition ( addr -- size )
@@ -548,14 +556,7 @@ AA268B49521E5A8B CONSTANT GPT-PREP-PARTITION-4
: try-dos-files ( -- found? )
no-mbr? IF false EXIT THEN
- \ disk-buf 0 byte 0-2 is a jump instruction in all FAT
- \ filesystems.
- \ e9 and eb are jump instructions in x86 assembler.
- disk-buf c@ e9 <> IF
- disk-buf c@ eb <>
- disk-buf 2+ c@ 90 <> or
- IF false EXIT THEN
- THEN
+ disk-buf fat-bootblock? 0= IF false EXIT THEN
s" fat-files" (interpose-filesystem)
true
;
--
2.4.3
next prev parent reply other threads:[~2015-06-30 11:02 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-06-30 11:01 [PATCH SLOF v3 0/5] GPT fixes/cleanup and LVM support with FAT Nikunj A Dadhania
2015-06-30 11:01 ` [PATCH SLOF v3 1/5] disk-label: simplify gpt-prep-partition? routine Nikunj A Dadhania
2015-06-30 11:01 ` [PATCH SLOF v3 2/5] introduce 8-byte LE helpers Nikunj A Dadhania
2015-06-30 11:01 ` [PATCH SLOF v3 3/5] disk-label: rename confusing "block" word Nikunj A Dadhania
2015-07-01 7:32 ` Segher Boessenkool
2015-07-02 5:47 ` Nikunj A Dadhania
2015-07-02 10:04 ` Segher Boessenkool
2015-07-02 10:14 ` Nikunj A Dadhania
2015-06-30 11:01 ` Nikunj A Dadhania [this message]
2015-06-30 11:01 ` [PATCH SLOF v3 5/5] disk-label: add support for booting from GPT FAT partition Nikunj A Dadhania
2015-06-30 11:28 ` Thomas Huth
2015-06-30 12:24 ` Nikunj A Dadhania
2015-06-30 18:57 ` Thomas Huth
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