snic: driver for Cisco SCSI HBA

Cisco has developed a new PCI HBA interface called sNIC, which stands for
SCSI NIC. This is a new storage feature supported on specialized network
adapter. The new PCI function provides a uniform host interface and abstracts
backend storage.

[jejb: fix up checkpatch errors]
Signed-off-by: Narsimhulu Musini <nmusini@cisco.com>
Signed-off-by: Sesidhar Baddela <sebaddel@cisco.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>

1 files changed, 414 insertions, 0 deletions

diff --git a/drivers/scsi/snic/snic.h b/drivers/scsi/snic/snic.h
new file mode 100644
index 000000000000..d7f5ba6ba84c
--- /dev/null
+++ b/drivers/scsi/snic/snic.h
@@ -0,0 +1,414 @@
+/*
+ * Copyright 2014 Cisco Systems, Inc.  All rights reserved.
+ *
+ * This program is free software; you may redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#ifndef _SNIC_H_
+#define _SNIC_H_
+
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/workqueue.h>
+#include <linux/bitops.h>
+#include <linux/mempool.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_host.h>
+
+#include "snic_disc.h"
+#include "snic_io.h"
+#include "snic_res.h"
+#include "snic_trc.h"
+#include "snic_stats.h"
+#include "vnic_dev.h"
+#include "vnic_wq.h"
+#include "vnic_cq.h"
+#include "vnic_intr.h"
+#include "vnic_stats.h"
+#include "vnic_snic.h"
+
+#define SNIC_DRV_NAME           "snic"
+#define SNIC_DRV_DESCRIPTION    "Cisco SCSI NIC Driver"
+#define SNIC_DRV_VERSION        "0.0.1.18"
+#define PFX                     SNIC_DRV_NAME ":"
+#define DFX                     SNIC_DRV_NAME "%d: "
+
+#define DESC_CLEAN_LOW_WATERMARK        8
+#define SNIC_UCSM_DFLT_THROTTLE_CNT_BLD 16 /* UCSM default throttle count */
+#define SNIC_MAX_IO_REQ                 50 /* scsi_cmnd tag map entries */
+#define SNIC_MIN_IO_REQ                 8  /* Min IO throttle count */
+#define SNIC_IO_LOCKS                   64 /* IO locks: power of 2 */
+#define SNIC_DFLT_QUEUE_DEPTH           32 /* Default Queue Depth */
+#define SNIC_MAX_QUEUE_DEPTH            64 /* Max Queue Depth */
+#define SNIC_DFLT_CMD_TIMEOUT           90 /* Extended tmo for FW */
+
+/*
+ * Tag bits used for special requests.
+ */
+#define SNIC_TAG_ABORT          BIT(30)         /* Tag indicating abort */
+#define SNIC_TAG_DEV_RST        BIT(29)         /* Tag for device reset */
+#define SNIC_TAG_IOCTL_DEV_RST  BIT(28)         /* Tag for User Device Reset */
+#define SNIC_TAG_MASK           (BIT(24) - 1)   /* Mask for lookup */
+#define SNIC_NO_TAG             -1
+
+/*
+ * Command flags to identify the type of command and for other future use
+ */
+#define SNIC_NO_FLAGS                   0
+#define SNIC_IO_INITIALIZED             BIT(0)
+#define SNIC_IO_ISSUED                  BIT(1)
+#define SNIC_IO_DONE                    BIT(2)
+#define SNIC_IO_REQ_NULL                BIT(3)
+#define SNIC_IO_ABTS_PENDING            BIT(4)
+#define SNIC_IO_ABORTED                 BIT(5)
+#define SNIC_IO_ABTS_ISSUED             BIT(6)
+#define SNIC_IO_TERM_ISSUED             BIT(7)
+#define SNIC_IO_ABTS_TIMEDOUT           BIT(8)
+#define SNIC_IO_ABTS_TERM_DONE          BIT(9)
+#define SNIC_IO_ABTS_TERM_REQ_NULL      BIT(10)
+#define SNIC_IO_ABTS_TERM_TIMEDOUT      BIT(11)
+#define SNIC_IO_INTERNAL_TERM_PENDING   BIT(12)
+#define SNIC_IO_INTERNAL_TERM_ISSUED    BIT(13)
+#define SNIC_DEVICE_RESET               BIT(14)
+#define SNIC_DEV_RST_ISSUED             BIT(15)
+#define SNIC_DEV_RST_TIMEDOUT           BIT(16)
+#define SNIC_DEV_RST_ABTS_ISSUED        BIT(17)
+#define SNIC_DEV_RST_TERM_ISSUED        BIT(18)
+#define SNIC_DEV_RST_DONE               BIT(19)
+#define SNIC_DEV_RST_REQ_NULL           BIT(20)
+#define SNIC_DEV_RST_ABTS_DONE          BIT(21)
+#define SNIC_DEV_RST_TERM_DONE          BIT(22)
+#define SNIC_DEV_RST_ABTS_PENDING       BIT(23)
+#define SNIC_DEV_RST_PENDING            BIT(24)
+#define SNIC_DEV_RST_NOTSUP             BIT(25)
+#define SNIC_SCSI_CLEANUP               BIT(26)
+#define SNIC_HOST_RESET_ISSUED          BIT(27)
+
+#define SNIC_ABTS_TIMEOUT               30000           /* msec */
+#define SNIC_LUN_RESET_TIMEOUT          30000           /* msec */
+#define SNIC_HOST_RESET_TIMEOUT         30000           /* msec */
+
+
+/*
+ * These are protected by the hashed req_lock.
+ */
+#define CMD_SP(Cmnd)            \
+        (((struct snic_internal_io_state *)scsi_cmd_priv(Cmnd))->rqi)
+#define CMD_STATE(Cmnd)         \
+        (((struct snic_internal_io_state *)scsi_cmd_priv(Cmnd))->state)
+#define CMD_ABTS_STATUS(Cmnd)   \
+        (((struct snic_internal_io_state *)scsi_cmd_priv(Cmnd))->abts_status)
+#define CMD_LR_STATUS(Cmnd)     \
+        (((struct snic_internal_io_state *)scsi_cmd_priv(Cmnd))->lr_status)
+#define CMD_FLAGS(Cmnd) \
+        (((struct snic_internal_io_state *)scsi_cmd_priv(Cmnd))->flags)
+
+#define SNIC_INVALID_CODE 0x100 /* Hdr Status val unused by firmware */
+
+#define SNIC_MAX_TARGET                 256
+#define SNIC_FLAGS_NONE                 (0)
+
+/* snic module params */
+extern unsigned int snic_max_qdepth;
+
+/* snic debugging */
+extern unsigned int snic_log_level;
+
+#define SNIC_MAIN_LOGGING       0x1
+#define SNIC_SCSI_LOGGING       0x2
+#define SNIC_ISR_LOGGING        0x8
+#define SNIC_DESC_LOGGING       0x10
+
+#define SNIC_CHECK_LOGGING(LEVEL, CMD)          \
+do {                                            \
+        if (unlikely(snic_log_level & LEVEL))   \
+                do {                            \
+                        CMD;                    \
+                } while (0);                    \
+} while (0)
+
+#define SNIC_MAIN_DBG(host, fmt, args...)       \
+        SNIC_CHECK_LOGGING(SNIC_MAIN_LOGGING,           \
+                shost_printk(KERN_INFO, host, fmt, ## args);)
+
+#define SNIC_SCSI_DBG(host, fmt, args...)       \
+        SNIC_CHECK_LOGGING(SNIC_SCSI_LOGGING,           \
+                shost_printk(KERN_INFO, host, fmt, ##args);)
+
+#define SNIC_DISC_DBG(host, fmt, args...)       \
+        SNIC_CHECK_LOGGING(SNIC_SCSI_LOGGING,           \
+                shost_printk(KERN_INFO, host, fmt, ##args);)
+
+#define SNIC_ISR_DBG(host, fmt, args...)        \
+        SNIC_CHECK_LOGGING(SNIC_ISR_LOGGING,            \
+                shost_printk(KERN_INFO, host, fmt, ##args);)
+
+#define SNIC_HOST_ERR(host, fmt, args...)               \
+        shost_printk(KERN_ERR, host, fmt, ##args)
+
+#define SNIC_HOST_INFO(host, fmt, args...)              \
+        shost_printk(KERN_INFO, host, fmt, ##args)
+
+#define SNIC_INFO(fmt, args...)                         \
+        pr_info(PFX fmt, ## args)
+
+#define SNIC_DBG(fmt, args...)                          \
+        pr_info(PFX fmt, ## args)
+
+#define SNIC_ERR(fmt, args...)                          \
+        pr_err(PFX fmt, ## args)
+
+#ifdef DEBUG
+#define SNIC_BUG_ON(EXPR) \
+        ({ \
+                if (EXPR) { \
+                        SNIC_ERR("SNIC BUG(%s)\n", #EXPR); \
+                        BUG_ON(EXPR); \
+                } \
+        })
+#else
+#define SNIC_BUG_ON(EXPR) \
+        ({ \
+                if (EXPR) { \
+                        SNIC_ERR("SNIC BUG(%s) at %s : %d\n", \
+                                 #EXPR, __func__, __LINE__); \
+                        WARN_ON_ONCE(EXPR); \
+                } \
+        })
+#endif
+
+/* Soft assert */
+#define SNIC_ASSERT_NOT_IMPL(EXPR) \
+        ({ \
+                if (EXPR) {\
+                        SNIC_INFO("Functionality not impl'ed at %s:%d\n", \
+                                  __func__, __LINE__); \
+                        WARN_ON_ONCE(EXPR); \
+                } \
+         })
+
+
+extern const char *snic_state_str[];
+
+enum snic_intx_intr_index {
+        SNIC_INTX_WQ_RQ_COPYWQ,
+        SNIC_INTX_ERR,
+        SNIC_INTX_NOTIFY,
+        SNIC_INTX_INTR_MAX,
+};
+
+enum snic_msix_intr_index {
+        SNIC_MSIX_WQ,
+        SNIC_MSIX_IO_CMPL,
+        SNIC_MSIX_ERR_NOTIFY,
+        SNIC_MSIX_INTR_MAX,
+};
+
+struct snic_msix_entry {
+        int requested;
+        char devname[IFNAMSIZ];
+        irqreturn_t (*isr)(int, void *);
+        void *devid;
+};
+
+enum snic_state {
+        SNIC_INIT = 0,
+        SNIC_ERROR,
+        SNIC_ONLINE,
+        SNIC_OFFLINE,
+        SNIC_FWRESET,
+};
+
+#define SNIC_WQ_MAX             1
+#define SNIC_CQ_IO_CMPL_MAX     1
+#define SNIC_CQ_MAX             (SNIC_WQ_MAX + SNIC_CQ_IO_CMPL_MAX)
+
+/* firmware version information */
+struct snic_fw_info {
+        u32     fw_ver;
+        u32     hid;                    /* u16 hid | u16 vnic id */
+        u32     max_concur_ios;         /* max concurrent ios */
+        u32     max_sgs_per_cmd;        /* max sgls per IO */
+        u32     max_io_sz;              /* max io size supported */
+        u32     hba_cap;                /* hba capabilities */
+        u32     max_tgts;               /* max tgts supported */
+        u16     io_tmo;                 /* FW Extended timeout */
+        struct completion *wait;        /* protected by snic lock*/
+};
+
+/*
+ * snic_work item : defined to process asynchronous events
+ */
+struct snic_work {
+        struct work_struct work;
+        u16     ev_id;
+        u64     *ev_data;
+};
+
+/*
+ * snic structure to represent SCSI vNIC
+ */
+struct snic {
+        /* snic specific members */
+        struct list_head list;
+        char name[IFNAMSIZ];
+        atomic_t state;
+        spinlock_t snic_lock;
+        struct completion *remove_wait;
+        bool in_remove;
+        bool stop_link_events;          /* stop processing link events */
+
+        /* discovery related */
+        struct snic_disc disc;
+
+        /* Scsi Host info */
+        struct Scsi_Host *shost;
+
+        /* vnic related structures */
+        struct vnic_dev_bar bar0;
+
+        struct vnic_stats *stats;
+        unsigned long stats_time;
+        unsigned long stats_reset_time;
+
+        struct vnic_dev *vdev;
+
+        /* hw resource info */
+        unsigned int wq_count;
+        unsigned int cq_count;
+        unsigned int intr_count;
+        unsigned int err_intr_offset;
+
+        int link_status; /* retrieved from svnic_dev_link_status() */
+        u32 link_down_cnt;
+
+        /* pci related */
+        struct pci_dev *pdev;
+        struct msix_entry msix_entry[SNIC_MSIX_INTR_MAX];
+        struct snic_msix_entry msix[SNIC_MSIX_INTR_MAX];
+
+        /* io related info */
+        mempool_t *req_pool[SNIC_REQ_MAX_CACHES]; /* (??) */
+        ____cacheline_aligned spinlock_t io_req_lock[SNIC_IO_LOCKS];
+
+        /* Maintain snic specific commands, cmds with no tag in spl_cmd_list */
+        ____cacheline_aligned spinlock_t spl_cmd_lock;
+        struct list_head spl_cmd_list;
+
+        unsigned int max_tag_id;
+        atomic_t ios_inflight;          /* io in flight counter */
+
+        struct vnic_snic_config config;
+
+        struct work_struct link_work;
+
+        /* firmware information */
+        struct snic_fw_info fwinfo;
+
+        /* Work for processing Target related work */
+        struct work_struct tgt_work;
+
+        /* Work for processing Discovery */
+        struct work_struct disc_work;
+
+        /* stats related */
+        unsigned int reset_stats;
+        atomic64_t io_cmpl_skip;
+        struct snic_stats s_stats;      /* Per SNIC driver stats */
+
+        /* platform specific */
+#ifdef CONFIG_SCSI_SNIC_DEBUG_FS
+        struct dentry *stats_host;      /* Per snic debugfs root */
+        struct dentry *stats_file;      /* Per snic debugfs file */
+        struct dentry *reset_stats_file;/* Per snic reset stats file */
+#endif
+
+        /* completion queue cache line section */
+        ____cacheline_aligned struct vnic_cq cq[SNIC_CQ_MAX];
+
+        /* work queue cache line section */
+        ____cacheline_aligned struct vnic_wq wq[SNIC_WQ_MAX];
+        spinlock_t wq_lock[SNIC_WQ_MAX];
+
+        /* interrupt resource cache line section */
+        ____cacheline_aligned struct vnic_intr intr[SNIC_MSIX_INTR_MAX];
+}; /* end of snic structure */
+
+/*
+ * SNIC Driver's Global Data
+ */
+struct snic_global {
+        struct list_head snic_list;
+        spinlock_t snic_list_lock;
+
+        struct kmem_cache *req_cache[SNIC_REQ_MAX_CACHES];
+
+        struct workqueue_struct *event_q;
+
+#ifdef CONFIG_SCSI_SNIC_DEBUG_FS
+        /* debugfs related global data */
+        struct dentry *trc_root;
+        struct dentry *stats_root;
+
+        struct snic_trc trc ____cacheline_aligned;
+#endif
+};
+
+extern struct snic_global *snic_glob;
+
+int snic_glob_init(void);
+void snic_glob_cleanup(void);
+
+extern struct workqueue_struct *snic_event_queue;
+extern struct device_attribute *snic_attrs[];
+
+int snic_queuecommand(struct Scsi_Host *, struct scsi_cmnd *);
+int snic_abort_cmd(struct scsi_cmnd *);
+int snic_device_reset(struct scsi_cmnd *);
+int snic_host_reset(struct scsi_cmnd *);
+int snic_reset(struct Scsi_Host *, struct scsi_cmnd *);
+void snic_shutdown_scsi_cleanup(struct snic *);
+
+
+int snic_request_intr(struct snic *);
+void snic_free_intr(struct snic *);
+int snic_set_intr_mode(struct snic *);
+void snic_clear_intr_mode(struct snic *);
+
+int snic_fwcq_cmpl_handler(struct snic *, int);
+int snic_wq_cmpl_handler(struct snic *, int);
+void snic_free_wq_buf(struct vnic_wq *, struct vnic_wq_buf *);
+
+
+void snic_log_q_error(struct snic *);
+void snic_handle_link_event(struct snic *);
+void snic_handle_link(struct work_struct *);
+
+int snic_queue_exch_ver_req(struct snic *);
+int snic_io_exch_ver_cmpl_handler(struct snic *, struct snic_fw_req *);
+
+int snic_queue_wq_desc(struct snic *, void *os_buf, u16 len);
+
+void snic_handle_untagged_req(struct snic *, struct snic_req_info *);
+void snic_release_untagged_req(struct snic *, struct snic_req_info *);
+void snic_free_all_untagged_reqs(struct snic *);
+int snic_get_conf(struct snic *);
+void snic_set_state(struct snic *, enum snic_state);
+int snic_get_state(struct snic *);
+const char *snic_state_to_str(unsigned int);
+void snic_hex_dump(char *, char *, int);
+void snic_print_desc(const char *fn, char *os_buf, int len);
+const char *show_opcode_name(int val);
+#endif /* _SNIC_H */