[SCSI] iscsi: convert xmit path to iscsi chunks

Convert xmit to iscsi chunks.

from michaelc@cs.wisc.edu:

Bug fixes, more digest integration, sg chaining conversion and other
sg wrapper changes, coding style sync up, and removal of io fields,
like pdu_sent, that are not needed.

Signed-off-by: Olaf Kirch <olaf.kirch@oracle.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

1 files changed, 15 insertions, 60 deletions

diff --git a/drivers/scsi/iscsi_tcp.h b/drivers/scsi/iscsi_tcp.h
index d49d87611e82..893cd2e1701e 100644
--- a/drivers/scsi/iscsi_tcp.h
+++ b/drivers/scsi/iscsi_tcp.h
@@ -24,35 +24,18 @@
 
 #include <scsi/libiscsi.h>
 
-/* xmit state machine */
-#define XMSTATE_IDLE                    0x0
-#define XMSTATE_CMD_HDR_INIT            0x1
-#define XMSTATE_CMD_HDR_XMIT            0x2
-#define XMSTATE_IMM_HDR                 0x4
-#define XMSTATE_IMM_DATA                0x8
-#define XMSTATE_UNS_INIT                0x10
-#define XMSTATE_UNS_HDR                 0x20
-#define XMSTATE_UNS_DATA                0x40
-#define XMSTATE_SOL_HDR                 0x80
-#define XMSTATE_SOL_DATA                0x100
-#define XMSTATE_W_PAD                   0x200
-#define XMSTATE_W_RESEND_PAD            0x400
-#define XMSTATE_W_RESEND_DATA_DIGEST    0x800
-#define XMSTATE_IMM_HDR_INIT            0x1000
-#define XMSTATE_SOL_HDR_INIT            0x2000
-
 #define ISCSI_SG_TABLESIZE              SG_ALL
 #define ISCSI_TCP_MAX_CMD_LEN           16
 
 struct crypto_hash;
 struct socket;
 struct iscsi_tcp_conn;
-struct iscsi_chunk;
+struct iscsi_segment;
 
-typedef int iscsi_chunk_done_fn_t(struct iscsi_tcp_conn *,
-                                  struct iscsi_chunk *);
+typedef int iscsi_segment_done_fn_t(struct iscsi_tcp_conn *,
+                                    struct iscsi_segment *);
 
-struct iscsi_chunk {
+struct iscsi_segment {
         unsigned char           *data;
         unsigned int            size;
         unsigned int            copied;
@@ -67,16 +50,14 @@ struct iscsi_chunk {
         struct scatterlist      *sg;
         void                    *sg_mapped;
         unsigned int            sg_offset;
-        unsigned int            sg_index;
-        unsigned int            sg_count;
 
-        iscsi_chunk_done_fn_t   *done;
+        iscsi_segment_done_fn_t *done;
 };
 
 /* Socket connection recieve helper */
 struct iscsi_tcp_recv {
         struct iscsi_hdr        *hdr;
-        struct iscsi_chunk      chunk;
+        struct iscsi_segment    segment;
 
         /* Allocate buffer for BHS + AHS */
         uint32_t                hdr_buf[64];
@@ -88,11 +69,8 @@ struct iscsi_tcp_recv {
 /* Socket connection send helper */
 struct iscsi_tcp_send {
         struct iscsi_hdr        *hdr;
-        struct iscsi_chunk      chunk;
-        struct iscsi_chunk      data_chunk;
-
-        /* Allocate buffer for BHS + AHS */
-        uint32_t                hdr_buf[64];
+        struct iscsi_segment    segment;
+        struct iscsi_segment    data_segment;
 };
 
 struct iscsi_tcp_conn {
@@ -118,29 +96,19 @@ struct iscsi_tcp_conn {
         uint32_t                sendpage_failures_cnt;
         uint32_t                discontiguous_hdr_cnt;
 
-        ssize_t (*sendpage)(struct socket *, struct page *, int, size_t, int);
-};
+        int                     error;
 
-struct iscsi_buf {
-        struct scatterlist      sg;
-        unsigned int            sent;
-        char                    use_sendmsg;
+        ssize_t (*sendpage)(struct socket *, struct page *, int, size_t, int);
 };
 
 struct iscsi_data_task {
         struct iscsi_data       hdr;                    /* PDU */
         char                    hdrext[ISCSI_DIGEST_SIZE];/* Header-Digest */
-        struct iscsi_buf        digestbuf;              /* digest buffer */
-        uint32_t                digest;                 /* data digest */
 };
 
 struct iscsi_tcp_mgmt_task {
         struct iscsi_hdr        hdr;
         char                    hdrext[ISCSI_DIGEST_SIZE]; /* Header-Digest */
-        int                     xmstate;        /* mgmt xmit progress */
-        struct iscsi_buf        headbuf;        /* header buffer */
-        struct iscsi_buf        sendbuf;        /* in progress buffer */
-        int                     sent;
 };
 
 struct iscsi_r2t_info {
@@ -148,13 +116,10 @@ struct iscsi_r2t_info {
         __be32                  exp_statsn;     /* copied from R2T */
         uint32_t                data_length;    /* copied from R2T */
         uint32_t                data_offset;    /* copied from R2T */
-        struct iscsi_buf        headbuf;        /* Data-Out Header Buffer */
-        struct iscsi_buf        sendbuf;        /* Data-Out in progress buffer*/
         int                     sent;           /* R2T sequence progress */
         int                     data_count;     /* DATA-Out payload progress */
-        struct scatterlist      *sg;            /* per-R2T SG list */
         int                     solicit_datasn;
-        struct iscsi_data_task   dtask;        /* which data task */
+        struct iscsi_data_task  dtask;          /* Data-Out header buf */
 };
 
 struct iscsi_tcp_cmd_task {
@@ -163,24 +128,14 @@ struct iscsi_tcp_cmd_task {
                 char                    hdrextbuf[ISCSI_MAX_AHS_SIZE +
                                                   ISCSI_DIGEST_SIZE];
         } hdr;
-        char                    pad[ISCSI_PAD_LEN];
-        int                     pad_count;              /* padded bytes */
-        struct iscsi_buf        headbuf;                /* header buf (xmit) */
-        struct iscsi_buf        sendbuf;                /* in progress buffer*/
-        int                     xmstate;                /* xmit xtate machine */
+
         int                     sent;
-        struct scatterlist      *sg;                    /* per-cmd SG list  */
-        struct scatterlist      *bad_sg;                /* assert statement */
-        int                     sg_count;               /* SG's to process  */
-        uint32_t                exp_datasn;             /* expected target's R2TSN/DataSN */
+        uint32_t                exp_datasn;     /* expected target's R2TSN/DataSN */
         int                     data_offset;
-        struct iscsi_r2t_info   *r2t;                   /* in progress R2T    */
+        struct iscsi_r2t_info   *r2t;           /* in progress R2T    */
         struct iscsi_pool       r2tpool;
         struct kfifo            *r2tqueue;
-        int                     digest_count;
-        uint32_t                immdigest;              /* for imm data */
-        struct iscsi_buf        immbuf;                 /* for imm data digest */
-        struct iscsi_data_task  unsol_dtask;    /* unsol data task */
+        struct iscsi_data_task  unsol_dtask;    /* Data-Out header buf */
 };
 
 #endif /* ISCSI_H */