linux/drivers/scsi/fcoe/fcoe.h

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/*
* Copyright(c) 2009 Intel Corporation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
*
* Maintained at www.Open-FCoE.org
*/
#ifndef _FCOE_H_
#define _FCOE_H_
#include <linux/skbuff.h>
#include <linux/kthread.h>
#define FCOE_MAX_QUEUE_DEPTH 256
#define FCOE_LOW_QUEUE_DEPTH 32
#define FCOE_WORD_TO_BYTE 4
#define FCOE_VERSION "0.1"
#define FCOE_NAME "fcoe"
#define FCOE_VENDOR "Open-FCoE.org"
#define FCOE_MAX_LUN 0xFFFF
#define FCOE_MAX_FCP_TARGET 256
#define FCOE_MAX_OUTSTANDING_COMMANDS 1024
#define FCOE_MIN_XID 0x0000 /* the min xid supported by fcoe_sw */
[SCSI] fcoe, libfc: adds per cpu exch pool within exchange manager(EM) Adds per cpu exch pool for these reasons:- 1. Currently an EM instance is shared across all cpus to manage all exches for all cpus. This required em_lock across all cpus for an exch alloc, free, lookup and reset each frame and that made em_lock expensive, so instead having per cpu exch pool with their own per cpu pool lock will likely reduce locking contention in fast path for an exch alloc, free and lookup. 2. Per cpu exch pool will likely improve cache hit ratio since all frames of an exch will be processed on the same cpu on which exch originated. This patch is only prep work to help in keeping complexity of next patch low, so this patch only sets up per cpu exch pool and related helper funcs to be used by next patch. The next patch fully makes use of per cpu exch pool in all code paths ie. tx, rx and reset. Divides per EM exch id range equally across all cpus to setup per cpu exch pool. This division is such that lower bits of exch id carries cpu number info on which exch originated, later a simple bitwise AND operation on exch id of incoming frame with fc_cpu_mask retrieves cpu number info to direct all frames to same cpu on which exch originated. This required a global fc_cpu_mask and fc_cpu_order initialized to max possible cpus number nr_cpu_ids rounded up to 2's power, this will be used in mapping exch id and exch ptr array index in pool during exch allocation, find or reset code paths. Adds a check in fc_exch_mgr_alloc() to ensure specified min_xid lower bits are zero since these bits are used to carry cpu info. Adds and initializes struct fc_exch_pool with all required fields to manage exches in pool. Allocates per cpu struct fc_exch_pool with memory for exches array for range of exches per pool. The exches array memory is followed by struct fc_exch_pool. Adds fc_exch_ptr_get/set() helper functions to get/set exch ptr in pool exches array at specified array index. Increases default FCOE_MAX_XID to 0x0FFF from 0x07EF, so that more exches are available per cpu after above described exch id range division across all cpus to each pool. Signed-off-by: Vasu Dev <vasu.dev@intel.com> Signed-off-by: Robert Love <robert.w.love@intel.com> Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-08-25 22:58:47 +02:00
#define FCOE_MAX_XID 0x0FFF /* the max xid supported by fcoe_sw */
/*
* Max MTU for FCoE: 14 (FCoE header) + 24 (FC header) + 2112 (max FC payload)
* + 4 (FC CRC) + 4 (FCoE trailer) = 2158 bytes
*/
#define FCOE_MTU 2158
unsigned int fcoe_debug_logging;
module_param_named(debug_logging, fcoe_debug_logging, int, S_IRUGO|S_IWUSR);
MODULE_PARM_DESC(debug_logging, "a bit mask of logging levels");
#define FCOE_LOGGING 0x01 /* General logging, not categorized */
#define FCOE_NETDEV_LOGGING 0x02 /* Netdevice logging */
#define FCOE_CHECK_LOGGING(LEVEL, CMD) \
do { \
if (unlikely(fcoe_debug_logging & LEVEL)) \
do { \
CMD; \
} while (0); \
} while (0)
#define FCOE_DBG(fmt, args...) \
FCOE_CHECK_LOGGING(FCOE_LOGGING, \
printk(KERN_INFO "fcoe: " fmt, ##args);)
#define FCOE_NETDEV_DBG(netdev, fmt, args...) \
FCOE_CHECK_LOGGING(FCOE_NETDEV_LOGGING, \
printk(KERN_INFO "fcoe: %s: " fmt, \
netdev->name, ##args);)
/**
* struct fcoe_percpu_s - The per-CPU context for FCoE receive threads
* @thread: The thread context
* @fcoe_rx_list: The queue of pending packets to process
* @page: The memory page for calculating frame trailer CRCs
* @crc_eof_offset: The offset into the CRC page pointing to available
* memory for a new trailer
*/
struct fcoe_percpu_s {
struct task_struct *thread;
struct sk_buff_head fcoe_rx_list;
struct page *crc_eof_page;
int crc_eof_offset;
};
/**
* struct fcoe_interface - A FCoE interface
* @list: Handle for a list of FCoE interfaces
* @netdev: The associated net device
* @fcoe_packet_type: FCoE packet type
* @fip_packet_type: FIP packet type
* @ctlr: The FCoE controller (for FIP)
* @oem: The offload exchange manager for all local port
* instances associated with this port
* @kref: The kernel reference
*
* This structure is 1:1 with a net devive.
*/
struct fcoe_interface {
struct list_head list;
struct net_device *netdev;
struct packet_type fcoe_packet_type;
struct packet_type fip_packet_type;
struct fcoe_ctlr ctlr;
struct fc_exch_mgr *oem;
struct kref kref;
};
/**
* struct fcoe_port - The FCoE private structure
* @fcoe: The associated fcoe interface
* @lport: The associated local port
* @fcoe_pending_queue: The pending Rx queue of skbs
* @fcoe_pending_queue_active: Indicates if the pending queue is active
* @timer: The queue timer
* @destroy_work: Handle for work context
* (to prevent RTNL deadlocks)
* @data_srt_addr: Source address for data
*
* An instance of this structure is to be allocated along with the
* Scsi_Host and libfc fc_lport structures.
*/
struct fcoe_port {
struct fcoe_interface *fcoe;
struct fc_lport *lport;
struct sk_buff_head fcoe_pending_queue;
u8 fcoe_pending_queue_active;
struct timer_list timer;
struct work_struct destroy_work;
u8 data_src_addr[ETH_ALEN];
};
#define fcoe_from_ctlr(fip) container_of(fip, struct fcoe_interface, ctlr)
/**
* fcoe_netdev() - Return the net device associated with a local port
* @lport: The local port to get the net device from
*/
static inline struct net_device *fcoe_netdev(const struct fc_lport *lport)
{
return ((struct fcoe_port *)lport_priv(lport))->fcoe->netdev;
}
#endif /* _FCOE_H_ */