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Revision a84a79e4d369a73c0130b5858199e949432da4c6 authored by Linus Torvalds on 17 October 2011, 15:24:24 UTC, committed by Linus Torvalds on 17 October 2011, 15:24:24 UTC 
Avoid using variable-length arrays in kernel/sys.c
 
The size is always valid, but variable-length arrays generate worse code
for no good reason (unless the function happens to be inlined and the
compiler sees the length for the simple constant it is).

Also, there seems to be some code generation problem on POWER, where
Henrik Bakken reports that register r28 can get corrupted under some
subtle circumstances (interrupt happening at the wrong time?).  That all
indicates some seriously broken compiler issues, but since variable
length arrays are bad regardless, there's little point in trying to
chase it down.

"Just don't do that, then".

Reported-by: Henrik Grindal Bakken <henribak@cisco.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent 8bc03e8
Raw File
target_core_pscsi.h 
#ifndef TARGET_CORE_PSCSI_H
#define TARGET_CORE_PSCSI_H

#define PSCSI_VERSION		"v4.0"

/* used in pscsi_find_alloc_len() */
#ifndef INQUIRY_DATA_SIZE
#define INQUIRY_DATA_SIZE	0x24
#endif

/* used in pscsi_add_device_to_list() */
#define PSCSI_DEFAULT_QUEUEDEPTH	1

#define PS_RETRY		5
#define PS_TIMEOUT_DISK		(15*HZ)
#define PS_TIMEOUT_OTHER	(500*HZ)

#include <linux/device.h>
#include <scsi/scsi_driver.h>
#include <scsi/scsi_device.h>
#include <linux/kref.h>
#include <linux/kobject.h>

struct pscsi_plugin_task {
	struct se_task pscsi_task;
	unsigned char pscsi_sense[SCSI_SENSE_BUFFERSIZE];
	int	pscsi_direction;
	int	pscsi_result;
	u32	pscsi_resid;
	struct request *pscsi_req;
	unsigned char pscsi_cdb[0];
} ____cacheline_aligned;

#define PDF_HAS_CHANNEL_ID	0x01
#define PDF_HAS_TARGET_ID	0x02
#define PDF_HAS_LUN_ID		0x04
#define PDF_HAS_VPD_UNIT_SERIAL 0x08
#define PDF_HAS_VPD_DEV_IDENT	0x10
#define PDF_HAS_VIRT_HOST_ID	0x20

struct pscsi_dev_virt {
	int	pdv_flags;
	int	pdv_host_id;
	int	pdv_channel_id;
	int	pdv_target_id;
	int	pdv_lun_id;
	struct block_device *pdv_bd;
	struct scsi_device *pdv_sd;
	struct se_hba *pdv_se_hba;
} ____cacheline_aligned;

typedef enum phv_modes {
	PHV_VIRUTAL_HOST_ID,
	PHV_LLD_SCSI_HOST_NO
} phv_modes_t;

struct pscsi_hba_virt {
	int			phv_host_id;
	phv_modes_t		phv_mode;
	struct Scsi_Host	*phv_lld_host;
} ____cacheline_aligned;

#endif   /*** TARGET_CORE_PSCSI_H ***/
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