From: Bart Van Assche <bvanassche@acm.org>
To: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Leon Romanovsky <leonro@mellanox.com>,
Doug Ledford <dledford@redhat.com>,
linux-rdma@vger.kernel.org, Bart Van Assche <bvanassche@acm.org>,
Nicolas Morey-Chaisemartin <nmoreychaisemartin@suse.com>
Subject: [PATCH v2 3/5] RDMA/srp: Apply the __packed attribute to members instead of structures
Date: Sun, 23 May 2021 21:12:09 -0700 [thread overview]
Message-ID: <20210524041211.9480-4-bvanassche@acm.org> (raw)
In-Reply-To: <20210524041211.9480-1-bvanassche@acm.org>
Applying the __packed attribute to an entire data structure results in
suboptimal code on architectures that do not support unaligned accesses.
Hence apply the __packed attribute only to those data members that are
not naturally aligned.
Cc: Nicolas Morey-Chaisemartin <nmoreychaisemartin@suse.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
---
include/scsi/srp.h | 26 +++++++++-----------------
1 file changed, 9 insertions(+), 17 deletions(-)
diff --git a/include/scsi/srp.h b/include/scsi/srp.h
index 177d8026e96f..dfe0984b58a9 100644
--- a/include/scsi/srp.h
+++ b/include/scsi/srp.h
@@ -107,10 +107,10 @@ struct srp_direct_buf {
* having the 20-byte structure padded to 24 bytes on 64-bit architectures.
*/
struct srp_indirect_buf {
- struct srp_direct_buf table_desc;
+ struct srp_direct_buf table_desc __packed __aligned(4);
__be32 len;
- struct srp_direct_buf desc_list[];
-} __attribute__((packed));
+ struct srp_direct_buf desc_list[] __packed __aligned(4);
+};
/* Immediate data buffer descriptor as defined in SRP2. */
struct srp_imm_buf {
@@ -175,13 +175,13 @@ struct srp_login_rsp {
u8 opcode;
u8 reserved1[3];
__be32 req_lim_delta;
- u64 tag;
+ u64 tag __packed __aligned(4);
__be32 max_it_iu_len;
__be32 max_ti_iu_len;
__be16 buf_fmt;
u8 rsp_flags;
u8 reserved2[25];
-} __attribute__((packed));
+};
struct srp_login_rej {
u8 opcode;
@@ -207,10 +207,6 @@ struct srp_t_logout {
u64 tag;
};
-/*
- * We need the packed attribute because the SRP spec only aligns the
- * 8-byte LUN field to 4 bytes.
- */
struct srp_tsk_mgmt {
u8 opcode;
u8 sol_not;
@@ -225,10 +221,6 @@ struct srp_tsk_mgmt {
u8 reserved5[8];
};
-/*
- * We need the packed attribute because the SRP spec only aligns the
- * 8-byte LUN field to 4 bytes.
- */
struct srp_cmd {
u8 opcode;
u8 sol_not;
@@ -266,7 +258,7 @@ struct srp_rsp {
u8 sol_not;
u8 reserved1[2];
__be32 req_lim_delta;
- u64 tag;
+ u64 tag __packed __aligned(4);
u8 reserved2[2];
u8 flags;
u8 status;
@@ -275,7 +267,7 @@ struct srp_rsp {
__be32 sense_data_len;
__be32 resp_data_len;
u8 data[];
-} __attribute__((packed));
+};
struct srp_cred_req {
u8 opcode;
@@ -301,13 +293,13 @@ struct srp_aer_req {
u8 sol_not;
u8 reserved[2];
__be32 req_lim_delta;
- u64 tag;
+ u64 tag __packed __aligned(4);
u32 reserved2;
struct scsi_lun lun;
__be32 sense_data_len;
u32 reserved3;
u8 sense_data[];
-} __attribute__((packed));
+};
struct srp_aer_rsp {
u8 opcode;
next prev parent reply other threads:[~2021-05-24 4:12 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-05-24 4:12 [PATCH v2 0/5] RDMA kernel patches for kernel v5.14 Bart Van Assche
2021-05-24 4:12 ` [PATCH v2 1/5] IB/hfi1: Move a function from a header file into a .c file Bart Van Assche
2021-05-24 4:12 ` [PATCH v2 2/5] RDMA/srp: Add more structure size checks Bart Van Assche
2021-05-24 4:12 ` Bart Van Assche [this message]
2021-05-24 4:12 ` [PATCH v2 4/5] RDMA/srp: Fix a recently introduced memory leak Bart Van Assche
2021-05-24 4:12 ` [PATCH v2 5/5] RDMA/srp: Make struct scsi_cmnd and struct srp_request adjacent Bart Van Assche
2021-05-28 23:23 ` [PATCH v2 0/5] RDMA kernel patches for kernel v5.14 Jason Gunthorpe
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210524041211.9480-4-bvanassche@acm.org \
--to=bvanassche@acm.org \
--cc=dledford@redhat.com \
--cc=jgg@ziepe.ca \
--cc=leonro@mellanox.com \
--cc=linux-rdma@vger.kernel.org \
--cc=nmoreychaisemartin@suse.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.