From: David Kozub <zub@linux.fjfi.cvut.cz>
To: Jens Axboe <axboe@kernel.dk>,
Jonathan Derrick <jonathan.derrick@intel.com>,
Scott Bauer <sbauer@plzdonthack.me>,
linux-block@vger.kernel.org, linux-kernel@vger.kernel.org
Cc: Jonas Rabenstein <jonas.rabenstein@studium.uni-erlangen.de>
Subject: [PATCH v4 09/16] block: sed-opal: split generation of bytestring header and content
Date: Fri, 1 Feb 2019 21:50:16 +0100 [thread overview]
Message-ID: <1549054223-12220-10-git-send-email-zub@linux.fjfi.cvut.cz> (raw)
In-Reply-To: <1549054223-12220-1-git-send-email-zub@linux.fjfi.cvut.cz>
From: Jonas Rabenstein <jonas.rabenstein@studium.uni-erlangen.de>
Split the header generation from the (normal) memcpy part if a
bytestring is copied into the command buffer. This allows in-place
generation of the bytestring content. For example, copy_from_user may be
used without an intermediate buffer.
Signed-off-by: Jonas Rabenstein <jonas.rabenstein@studium.uni-erlangen.de>
Reviewed-by: Scott Bauer <sbauer@plzdonthack.me>
---
block/sed-opal.c | 23 +++++++++++++++--------
1 file changed, 15 insertions(+), 8 deletions(-)
diff --git a/block/sed-opal.c b/block/sed-opal.c
index 4225f23b2165..4b0a63b9d7c9 100644
--- a/block/sed-opal.c
+++ b/block/sed-opal.c
@@ -586,14 +586,11 @@ static void add_token_u64(int *err, struct opal_dev *cmd, u64 number)
add_token_u8(err, cmd, number >> (len * 8));
}
-static void add_token_bytestring(int *err, struct opal_dev *cmd,
- const u8 *bytestring, size_t len)
+static u8 *add_bytestring_header(int *err, struct opal_dev *cmd, size_t len)
{
size_t header_len = 1;
bool is_short_atom = true;
-
- if (*err)
- return;
+ char *start;
if (len & ~SHORT_ATOM_LEN_MASK) {
header_len = 2;
@@ -602,17 +599,27 @@ static void add_token_bytestring(int *err, struct opal_dev *cmd,
if (!can_add(err, cmd, header_len + len)) {
pr_debug("Error adding bytestring: end of buffer.\n");
- return;
+ return NULL;
}
if (is_short_atom)
add_short_atom_header(cmd, true, false, len);
else
add_medium_atom_header(cmd, true, false, len);
+ start = &cmd->cmd[cmd->pos];
+ return start;
+}
- memcpy(&cmd->cmd[cmd->pos], bytestring, len);
- cmd->pos += len;
+static void add_token_bytestring(int *err, struct opal_dev *cmd,
+ const u8 *bytestring, size_t len)
+{
+ u8 *start;
+ start = add_bytestring_header(err, cmd, len);
+ if (!start)
+ return;
+ memcpy(start, bytestring, len);
+ cmd->pos += len;
}
static int build_locking_range(u8 *buffer, size_t length, u8 lr)
--
2.20.1
next prev parent reply other threads:[~2019-02-01 20:52 UTC|newest]
Thread overview: 64+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-02-01 20:50 [PATCH v4 00/16] block: sed-opal: support shadow MBR done flag and write David Kozub
2019-02-01 20:50 ` [PATCH v4 01/16] block: sed-opal: fix typos and formatting David Kozub
2019-02-04 14:42 ` Christoph Hellwig
2019-02-04 20:28 ` David Kozub
2019-02-08 22:56 ` Derrick, Jonathan
2019-02-01 20:50 ` [PATCH v4 02/16] block: sed-opal: use correct macro for method length David Kozub
2019-02-04 14:43 ` Christoph Hellwig
2019-02-08 22:56 ` Derrick, Jonathan
2019-02-01 20:50 ` [PATCH v4 03/16] block: sed-opal: unify space check in add_token_* David Kozub
2019-02-04 14:44 ` Christoph Hellwig
2019-02-04 21:07 ` David Kozub
2019-02-04 21:09 ` Christoph Hellwig
2019-02-08 22:57 ` Derrick, Jonathan
2019-02-01 20:50 ` [PATCH v4 04/16] block: sed-opal: close parameter list in cmd_finalize David Kozub
2019-02-04 14:44 ` Christoph Hellwig
2019-02-08 22:57 ` Derrick, Jonathan
2019-02-01 20:50 ` [PATCH v4 05/16] block: sed-opal: unify cmd start David Kozub
2019-02-04 14:45 ` Christoph Hellwig
2019-02-08 22:57 ` Derrick, Jonathan
2019-02-01 20:50 ` [PATCH v4 06/16] block: sed-opal: unify error handling of responses David Kozub
2019-02-04 14:45 ` Christoph Hellwig
2019-02-01 20:50 ` [PATCH v4 07/16] block: sed-opal: reuse response_get_token to decrease code duplication David Kozub
2019-02-04 14:46 ` Christoph Hellwig
2019-02-08 22:57 ` Derrick, Jonathan
2019-02-01 20:50 ` [PATCH v4 08/16] block: sed-opal: print failed function address David Kozub
2019-02-04 14:46 ` Christoph Hellwig
2019-02-01 20:50 ` David Kozub [this message]
2019-02-04 14:48 ` [PATCH v4 09/16] block: sed-opal: split generation of bytestring header and content Christoph Hellwig
2019-02-08 22:58 ` Derrick, Jonathan
2019-02-01 20:50 ` [PATCH v4 10/16] block: sed-opal: add ioctl for done-mark of shadow mbr David Kozub
2019-02-04 14:52 ` Christoph Hellwig
2019-02-07 22:56 ` David Kozub
2019-02-08 0:44 ` Derrick, Jonathan
2019-02-08 1:37 ` Scott Bauer
2019-02-10 18:26 ` Scott Bauer
2019-02-10 20:25 ` David Kozub
2019-02-01 20:50 ` [PATCH v4 11/16] block: sed-opal: ioctl for writing to " David Kozub
2019-02-04 17:58 ` kbuild test robot
2019-02-08 22:58 ` Derrick, Jonathan
2019-02-01 20:50 ` [PATCH v4 12/16] block: sed-opal: unify retrieval of table columns David Kozub
2019-02-04 14:56 ` Christoph Hellwig
2019-02-08 22:58 ` Derrick, Jonathan
2019-02-01 20:50 ` [PATCH v4 13/16] block: sed-opal: check size of shadow mbr David Kozub
2019-02-08 22:58 ` Derrick, Jonathan
2019-02-10 20:05 ` David Kozub
2019-02-11 21:27 ` Derrick, Jonathan
2019-02-01 20:50 ` [PATCH v4 14/16] block: sed-opal: pass steps via argument rather than via opal_dev David Kozub
2019-02-04 14:57 ` Christoph Hellwig
2019-02-01 20:50 ` [PATCH v4 15/16] block: sed-opal: don't repeat opal_discovery0 in each steps array David Kozub
2019-02-04 15:01 ` Christoph Hellwig
2019-02-04 22:44 ` David Kozub
2019-02-08 22:59 ` Derrick, Jonathan
2019-02-10 17:46 ` David Kozub
2019-02-11 17:22 ` Derrick, Jonathan
2019-02-01 20:50 ` [PATCH v4 16/16] block: sed-opal: rename next to execute_steps David Kozub
2019-02-04 15:01 ` Christoph Hellwig
2019-02-08 22:59 ` Derrick, Jonathan
2019-02-04 8:55 ` David Kozub
2019-02-04 9:44 ` [PATCH v4 00/16] block: sed-opal: support shadow MBR done flag and write David Kozub
2019-02-04 15:04 ` Christoph Hellwig
2019-02-04 15:36 ` Scott Bauer
2019-02-04 15:44 ` Christoph Hellwig
2019-02-04 23:06 ` David Kozub
2019-02-05 6:57 ` Christoph Hellwig
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