freebsd-skq/sys/cam/cam_xpt_internal.h
scottl cd4455d638 MFC Alexander Motin's direct dispatch, multi-queue, and finer-grained
locking support for CAM

r256826:
Fix several target mode SIMs to not blindly clear ccb_h.flags field of
ATIO CCBs.  Not all CCB flags there belong to them.

r256836:
Remove hard limit on number of BIOs handled with one ATA TRIM request.

r256843:
Merge CAM locking changes from the projects/camlock branch to radically
reduce lock congestion and improve SMP scalability of the SCSI/ATA stack,
preparing the ground for the coming next GEOM direct dispatch support.

r256888:
Unconditionally acquire periph reference on CCB allocation failure.

r256895:
Fix memory and references leak due to unfreed path.

r256960:
Move CAM_UNQUEUED_INDEX setting to the last moment and under the periph lock.
This fixes race condition with cam_periph_ccbwait(), causing use-after-free.

r256975:
Minor (mostly cosmetical) addition to r256960.

r257054:
Some microoptimizations for da and ada drivers:
 - Replace ordered_tag_count counter with single flag;
 - From da remove outstanding_cmds counter, duplicating pending_ccbs list;
 - From da_softc remove unused links field.

r257482:
Fix lock recursion, triggered by `smartctl -a /dev/adaX`.

r257501:
Make getenv_*() functions and respectively TUNABLE_*_FETCH() macros not
allocate memory and so not require sleepable environment.  getenv() has
already used on-stack temporary storage, so just use it more rationally.
getenv_string() receives buffer as argument, so don't need another one.

r257914:
Some CAM locks polishing:
 - Fix LOR and possible lock recursion when handling high-power commands.
Introduce new lock to protect left power quota and list of frozen devices.
 - Correct locking around xpt periph creation.
 - Remove seems never used XPT_FLAG_OPEN xpt periph flag.

Again, Netflix assisted with testing the merge, but all of the credit goes
to Alexander and iX Systems.

Submitted by:	mav
Sponsored by:	iX Systems
2014-01-07 01:51:48 +00:00

181 lines
5.8 KiB
C

/*-
* Copyright 2009 Scott Long
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions, and the following disclaimer,
* without modification, immediately at the beginning of the file.
* 2. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _CAM_CAM_XPT_INTERNAL_H
#define _CAM_CAM_XPT_INTERNAL_H 1
#include <sys/taskqueue.h>
/* Forward Declarations */
struct cam_eb;
struct cam_et;
struct cam_ed;
typedef struct cam_ed * (*xpt_alloc_device_func)(struct cam_eb *bus,
struct cam_et *target,
lun_id_t lun_id);
typedef void (*xpt_release_device_func)(struct cam_ed *device);
typedef void (*xpt_action_func)(union ccb *start_ccb);
typedef void (*xpt_dev_async_func)(u_int32_t async_code,
struct cam_eb *bus,
struct cam_et *target,
struct cam_ed *device,
void *async_arg);
typedef void (*xpt_announce_periph_func)(struct cam_periph *periph);
struct xpt_xport {
xpt_alloc_device_func alloc_device;
xpt_release_device_func reldev;
xpt_action_func action;
xpt_dev_async_func async;
xpt_announce_periph_func announce;
};
/*
* The CAM EDT (Existing Device Table) contains the device information for
* all devices for all busses in the system. The table contains a
* cam_ed structure for each device on the bus.
*/
struct cam_ed {
cam_pinfo devq_entry;
TAILQ_ENTRY(cam_ed) links;
struct cam_et *target;
struct cam_sim *sim;
lun_id_t lun_id;
struct cam_ccbq ccbq; /* Queue of pending ccbs */
struct async_list asyncs; /* Async callback info for this B/T/L */
struct periph_list periphs; /* All attached devices */
u_int generation; /* Generation number */
void *quirk; /* Oddities about this device */
u_int maxtags;
u_int mintags;
cam_proto protocol;
u_int protocol_version;
cam_xport transport;
u_int transport_version;
struct scsi_inquiry_data inq_data;
uint8_t *supported_vpds;
uint8_t supported_vpds_len;
uint32_t device_id_len;
uint8_t *device_id;
uint8_t physpath_len;
uint8_t *physpath; /* physical path string form */
uint32_t rcap_len;
uint8_t *rcap_buf;
struct ata_params ident_data;
u_int8_t inq_flags; /*
* Current settings for inquiry flags.
* This allows us to override settings
* like disconnection and tagged
* queuing for a device.
*/
u_int8_t queue_flags; /* Queue flags from the control page */
u_int8_t serial_num_len;
u_int8_t *serial_num;
u_int32_t flags;
#define CAM_DEV_UNCONFIGURED 0x01
#define CAM_DEV_REL_TIMEOUT_PENDING 0x02
#define CAM_DEV_REL_ON_COMPLETE 0x04
#define CAM_DEV_REL_ON_QUEUE_EMPTY 0x08
#define CAM_DEV_TAG_AFTER_COUNT 0x20
#define CAM_DEV_INQUIRY_DATA_VALID 0x40
#define CAM_DEV_IN_DV 0x80
#define CAM_DEV_DV_HIT_BOTTOM 0x100
#define CAM_DEV_IDENTIFY_DATA_VALID 0x200
u_int32_t tag_delay_count;
#define CAM_TAG_DELAY_COUNT 5
u_int32_t tag_saved_openings;
u_int32_t refcount;
struct callout callout;
STAILQ_ENTRY(cam_ed) highpowerq_entry;
struct mtx device_mtx;
struct task device_destroy_task;
};
/*
* Each target is represented by an ET (Existing Target). These
* entries are created when a target is successfully probed with an
* identify, and removed when a device fails to respond after a number
* of retries, or a bus rescan finds the device missing.
*/
struct cam_et {
TAILQ_HEAD(, cam_ed) ed_entries;
TAILQ_ENTRY(cam_et) links;
struct cam_eb *bus;
target_id_t target_id;
u_int32_t refcount;
u_int generation;
struct timeval last_reset;
u_int rpl_size;
struct scsi_report_luns_data *luns;
struct mtx luns_mtx; /* Protection for luns field. */
};
/*
* Each bus is represented by an EB (Existing Bus). These entries
* are created by calls to xpt_bus_register and deleted by calls to
* xpt_bus_deregister.
*/
struct cam_eb {
TAILQ_HEAD(, cam_et) et_entries;
TAILQ_ENTRY(cam_eb) links;
path_id_t path_id;
struct cam_sim *sim;
struct timeval last_reset;
u_int32_t flags;
#define CAM_EB_RUNQ_SCHEDULED 0x01
u_int32_t refcount;
u_int generation;
device_t parent_dev;
struct xpt_xport *xport;
struct mtx eb_mtx; /* Bus topology mutex. */
};
struct cam_path {
struct cam_periph *periph;
struct cam_eb *bus;
struct cam_et *target;
struct cam_ed *device;
};
struct xpt_xport * scsi_get_xport(void);
struct xpt_xport * ata_get_xport(void);
struct cam_ed * xpt_alloc_device(struct cam_eb *bus,
struct cam_et *target,
lun_id_t lun_id);
void xpt_acquire_device(struct cam_ed *device);
void xpt_release_device(struct cam_ed *device);
u_int32_t xpt_dev_ccbq_resize(struct cam_path *path, int newopenings);
void xpt_start_tags(struct cam_path *path);
void xpt_stop_tags(struct cam_path *path);
MALLOC_DECLARE(M_CAMXPT);
#endif