arcmsr: simplify ioctl data read/write

Signed-off-by: Ching Huang <ching 2048@areca.com.tw>
Reviewed-by: Tomas Henzl <thenzl@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

diff --git a/drivers/scsi/arcmsr/arcmsr.h b/drivers/scsi/arcmsr/arcmsr.h
index d1c78efc202e323bc273e0cb5db2d4360456b80b..3bcaaac0ae4bb5080b0d4c64223e20d7a8754dfa 100644 (file)
--- a/drivers/scsi/arcmsr/arcmsr.h
+++ b/drivers/scsi/arcmsr/arcmsr.h
@@ -52,7 +52,7 @@ struct device_attribute;
        #define ARCMSR_MAX_FREECCB_NUM  320
 #define ARCMSR_MAX_OUTSTANDING_CMD     255
 #endif
-#define ARCMSR_DRIVER_VERSION          "v1.30.00.04-20140428"
+#define ARCMSR_DRIVER_VERSION          "v1.30.00.04-20140919"
 #define ARCMSR_SCSI_INITIATOR_ID                                               255
 #define ARCMSR_MAX_XFER_SECTORS                                                        512
 #define ARCMSR_MAX_XFER_SECTORS_B                                              4096
@@ -107,10 +107,11 @@ struct CMD_MESSAGE
 **        IOP Message Transfer Data for user space
 *******************************************************************************
 */
+#define        ARCMSR_API_DATA_BUFLEN  1032
 struct CMD_MESSAGE_FIELD
 {
     struct CMD_MESSAGE                 cmdmessage;
-    uint8_t                            messagedatabuffer[1032];
+    uint8_t                            messagedatabuffer[ARCMSR_API_DATA_BUFLEN];
 };
 /* IOP message transfer */
 #define ARCMSR_MESSAGE_FAIL                    0x0001
@@ -678,15 +679,15 @@ struct AdapterControlBlock
        unsigned int                            uncache_size;
        uint8_t                         rqbuffer[ARCMSR_MAX_QBUFFER];
        /* data collection buffer for read from 80331 */
-       int32_t                         rqbuf_firstindex;
+       int32_t                         rqbuf_getIndex;
        /* first of read buffer  */
-       int32_t                         rqbuf_lastindex;
+       int32_t                         rqbuf_putIndex;
        /* last of read buffer   */
        uint8_t                         wqbuffer[ARCMSR_MAX_QBUFFER];
        /* data collection buffer for write to 80331  */
-       int32_t                         wqbuf_firstindex;
+       int32_t                         wqbuf_getIndex;
        /* first of write buffer */
-       int32_t                         wqbuf_lastindex;
+       int32_t                         wqbuf_putIndex;
        /* last of write buffer  */
        uint8_t                         devstate[ARCMSR_MAX_TARGETID][ARCMSR_MAX_TARGETLUN];
        /* id0 ..... id15, lun0...lun7 */

diff --git a/drivers/scsi/arcmsr/arcmsr_attr.c b/drivers/scsi/arcmsr/arcmsr_attr.c
index 16422adcc531269bb6666ba437950dbfc333eadc..9c86481f779f7901e3a615f4f24aa100ee4195d5 100644 (file)
--- a/drivers/scsi/arcmsr/arcmsr_attr.c
+++ b/drivers/scsi/arcmsr/arcmsr_attr.c
@@ -50,6 +50,7 @@
 #include <linux/errno.h>
 #include <linux/delay.h>
 #include <linux/pci.h>
+#include <linux/circ_buf.h>
 
 #include <scsi/scsi_cmnd.h>
 #include <scsi/scsi_device.h>
@@ -68,7 +69,7 @@ static ssize_t arcmsr_sysfs_iop_message_read(struct file *filp,
        struct device *dev = container_of(kobj,struct device,kobj);
        struct Scsi_Host *host = class_to_shost(dev);
        struct AdapterControlBlock *acb = (struct AdapterControlBlock *) host->hostdata;
-       uint8_t *pQbuffer,*ptmpQbuffer;
+       uint8_t *ptmpQbuffer;
        int32_t allxfer_len = 0;
        unsigned long flags;
 
@@ -78,57 +79,22 @@ static ssize_t arcmsr_sysfs_iop_message_read(struct file *filp,
        /* do message unit read. */
        ptmpQbuffer = (uint8_t *)buf;
        spin_lock_irqsave(&acb->rqbuffer_lock, flags);
-       if (acb->rqbuf_firstindex != acb->rqbuf_lastindex) {
-               pQbuffer = &acb->rqbuffer[acb->rqbuf_firstindex];
-               if (acb->rqbuf_firstindex > acb->rqbuf_lastindex) {
-                       if ((ARCMSR_MAX_QBUFFER - acb->rqbuf_firstindex) >= 1032) {
-                               memcpy(ptmpQbuffer, pQbuffer, 1032);
-                               acb->rqbuf_firstindex += 1032;
-                               acb->rqbuf_firstindex %= ARCMSR_MAX_QBUFFER;
-                               allxfer_len = 1032;
-                       } else {
-                               if (((ARCMSR_MAX_QBUFFER - acb->rqbuf_firstindex)
-                                       + acb->rqbuf_lastindex) > 1032) {
-                                       memcpy(ptmpQbuffer, pQbuffer,
-                                               ARCMSR_MAX_QBUFFER
-                                               - acb->rqbuf_firstindex);
-                                       ptmpQbuffer += ARCMSR_MAX_QBUFFER
-                                               - acb->rqbuf_firstindex;
-                                       memcpy(ptmpQbuffer, acb->rqbuffer, 1032
-                                               - (ARCMSR_MAX_QBUFFER -
-                                               acb->rqbuf_firstindex));
-                                       acb->rqbuf_firstindex = 1032 -
-                                               (ARCMSR_MAX_QBUFFER -
-                                               acb->rqbuf_firstindex);
-                                       allxfer_len = 1032;
-                               } else {
-                                       memcpy(ptmpQbuffer, pQbuffer,
-                                               ARCMSR_MAX_QBUFFER -
-                                               acb->rqbuf_firstindex);
-                                       ptmpQbuffer += ARCMSR_MAX_QBUFFER -
-                                               acb->rqbuf_firstindex;
-                                       memcpy(ptmpQbuffer, acb->rqbuffer,
-                                               acb->rqbuf_lastindex);
-                                       allxfer_len = ARCMSR_MAX_QBUFFER -
-                                               acb->rqbuf_firstindex +
-                                               acb->rqbuf_lastindex;
-                                       acb->rqbuf_firstindex =
-                                               acb->rqbuf_lastindex;
-                               }
-                       }
-               } else {
-                       if ((acb->rqbuf_lastindex - acb->rqbuf_firstindex) > 1032) {
-                               memcpy(ptmpQbuffer, pQbuffer, 1032);
-                               acb->rqbuf_firstindex += 1032;
-                               allxfer_len = 1032;
-                       } else {
-                               memcpy(ptmpQbuffer, pQbuffer, acb->rqbuf_lastindex
-                                       - acb->rqbuf_firstindex);
-                               allxfer_len = acb->rqbuf_lastindex -
-                                       acb->rqbuf_firstindex;
-                               acb->rqbuf_firstindex = acb->rqbuf_lastindex;
-                       }
+       if (acb->rqbuf_getIndex != acb->rqbuf_putIndex) {
+               unsigned int tail = acb->rqbuf_getIndex;
+               unsigned int head = acb->rqbuf_putIndex;
+               unsigned int cnt_to_end = CIRC_CNT_TO_END(head, tail, ARCMSR_MAX_QBUFFER);
+
+               allxfer_len = CIRC_CNT(head, tail, ARCMSR_MAX_QBUFFER);
+               if (allxfer_len > ARCMSR_API_DATA_BUFLEN)
+                       allxfer_len = ARCMSR_API_DATA_BUFLEN;
+
+               if (allxfer_len <= cnt_to_end)
+                       memcpy(ptmpQbuffer, acb->rqbuffer + tail, allxfer_len);
+               else {
+                       memcpy(ptmpQbuffer, acb->rqbuffer + tail, cnt_to_end);
+                       memcpy(ptmpQbuffer + cnt_to_end, acb->rqbuffer, allxfer_len - cnt_to_end);
                }
+               acb->rqbuf_getIndex = (acb->rqbuf_getIndex + allxfer_len) % ARCMSR_MAX_QBUFFER;
        }
        if (acb->acb_flags & ACB_F_IOPDATA_OVERFLOW) {
                struct QBUFFER __iomem *prbuffer;
@@ -150,47 +116,42 @@ static ssize_t arcmsr_sysfs_iop_message_write(struct file *filp,
        struct device *dev = container_of(kobj,struct device,kobj);
        struct Scsi_Host *host = class_to_shost(dev);
        struct AdapterControlBlock *acb = (struct AdapterControlBlock *) host->hostdata;
-       int32_t my_empty_len, user_len, wqbuf_firstindex, wqbuf_lastindex;
+       int32_t user_len, cnt2end;
        uint8_t *pQbuffer, *ptmpuserbuffer;
        unsigned long flags;
 
        if (!capable(CAP_SYS_ADMIN))
                return -EACCES;
-       if (count > 1032)
+       if (count > ARCMSR_API_DATA_BUFLEN)
                return -EINVAL;
        /* do message unit write. */
        ptmpuserbuffer = (uint8_t *)buf;
        user_len = (int32_t)count;
        spin_lock_irqsave(&acb->wqbuffer_lock, flags);
-       wqbuf_lastindex = acb->wqbuf_lastindex;
-       wqbuf_firstindex = acb->wqbuf_firstindex;
-       if (wqbuf_lastindex != wqbuf_firstindex) {
+       if (acb->wqbuf_putIndex != acb->wqbuf_getIndex) {
                arcmsr_write_ioctldata2iop(acb);
                spin_unlock_irqrestore(&acb->wqbuffer_lock, flags);
                return 0;       /*need retry*/
        } else {
-               my_empty_len = (wqbuf_firstindex-wqbuf_lastindex - 1)
-                       &(ARCMSR_MAX_QBUFFER - 1);
-               if (my_empty_len >= user_len) {
-                       while (user_len > 0) {
-                               pQbuffer = &acb->wqbuffer[acb->wqbuf_lastindex];
-                               memcpy(pQbuffer, ptmpuserbuffer, 1);
-                               acb->wqbuf_lastindex++;
-                               acb->wqbuf_lastindex %= ARCMSR_MAX_QBUFFER;
-                               ptmpuserbuffer++;
-                               user_len--;
-                       }
-                       if (acb->acb_flags & ACB_F_MESSAGE_WQBUFFER_CLEARED) {
-                               acb->acb_flags &=
-                                       ~ACB_F_MESSAGE_WQBUFFER_CLEARED;
-                               arcmsr_write_ioctldata2iop(acb);
-                       }
-                       spin_unlock_irqrestore(&acb->wqbuffer_lock, flags);
-                       return count;
-               } else {
-                       spin_unlock_irqrestore(&acb->wqbuffer_lock, flags);
-                       return 0;       /*need retry*/
+               pQbuffer = &acb->wqbuffer[acb->wqbuf_putIndex];
+               cnt2end = ARCMSR_MAX_QBUFFER - acb->wqbuf_putIndex;
+               if (user_len > cnt2end) {
+                       memcpy(pQbuffer, ptmpuserbuffer, cnt2end);
+                       ptmpuserbuffer += cnt2end;
+                       user_len -= cnt2end;
+                       acb->wqbuf_putIndex = 0;
+                       pQbuffer = acb->wqbuffer;
                }
+               memcpy(pQbuffer, ptmpuserbuffer, user_len);
+               acb->wqbuf_putIndex += user_len;
+               acb->wqbuf_putIndex %= ARCMSR_MAX_QBUFFER;
+               if (acb->acb_flags & ACB_F_MESSAGE_WQBUFFER_CLEARED) {
+                       acb->acb_flags &=
+                               ~ACB_F_MESSAGE_WQBUFFER_CLEARED;
+                       arcmsr_write_ioctldata2iop(acb);
+               }
+               spin_unlock_irqrestore(&acb->wqbuffer_lock, flags);
+               return count;
        }
 }
 
@@ -215,12 +176,12 @@ static ssize_t arcmsr_sysfs_iop_message_clear(struct file *filp,
                | ACB_F_MESSAGE_RQBUFFER_CLEARED
                | ACB_F_MESSAGE_WQBUFFER_READED);
        spin_lock_irqsave(&acb->rqbuffer_lock, flags);
-       acb->rqbuf_firstindex = 0;
-       acb->rqbuf_lastindex = 0;
+       acb->rqbuf_getIndex = 0;
+       acb->rqbuf_putIndex = 0;
        spin_unlock_irqrestore(&acb->rqbuffer_lock, flags);
        spin_lock_irqsave(&acb->wqbuffer_lock, flags);
-       acb->wqbuf_firstindex = 0;
-       acb->wqbuf_lastindex = 0;
+       acb->wqbuf_getIndex = 0;
+       acb->wqbuf_putIndex = 0;
        spin_unlock_irqrestore(&acb->wqbuffer_lock, flags);
        pQbuffer = acb->rqbuffer;
        memset(pQbuffer, 0, sizeof (struct QBUFFER));
@@ -234,7 +195,7 @@ static struct bin_attribute arcmsr_sysfs_message_read_attr = {
                .name = "mu_read",
                .mode = S_IRUSR ,
        },
-       .size = 1032,
+       .size = ARCMSR_API_DATA_BUFLEN,
        .read = arcmsr_sysfs_iop_message_read,
 };
 
@@ -243,7 +204,7 @@ static struct bin_attribute arcmsr_sysfs_message_write_attr = {
                .name = "mu_write",
                .mode = S_IWUSR,
        },
-       .size = 1032,
+       .size = ARCMSR_API_DATA_BUFLEN,
        .write = arcmsr_sysfs_iop_message_write,
 };
 

diff --git a/drivers/scsi/arcmsr/arcmsr_hba.c b/drivers/scsi/arcmsr/arcmsr_hba.c
index 0dd38ccc94700557fa9230862f8243b104011e5f..0b44fb5ee4852044a5e7ba52724408bfdcfe7f1d 100644 (file)
--- a/drivers/scsi/arcmsr/arcmsr_hba.c
+++ b/drivers/scsi/arcmsr/arcmsr_hba.c
@@ -58,6 +58,7 @@
 #include <linux/slab.h>
 #include <linux/pci.h>
 #include <linux/aer.h>
+#include <linux/circ_buf.h>
 #include <asm/dma.h>
 #include <asm/io.h>
 #include <asm/uaccess.h>
@@ -1701,16 +1702,15 @@ arcmsr_Read_iop_rqbuffer_in_DWORD(struct AdapterControlBlock *acb,
                buf2 = (uint32_t *)buf1;
        }
        while (iop_len > 0) {
-               pQbuffer = &acb->rqbuffer[acb->rqbuf_lastindex];
+               pQbuffer = &acb->rqbuffer[acb->rqbuf_putIndex];
                *pQbuffer = *buf1;
-               acb->rqbuf_lastindex++;
+               acb->rqbuf_putIndex++;
                /* if last, index number set it to 0 */
-               acb->rqbuf_lastindex %= ARCMSR_MAX_QBUFFER;
+               acb->rqbuf_putIndex %= ARCMSR_MAX_QBUFFER;
                buf1++;
                iop_len--;
        }
-       if (buf2)
-               kfree(buf2);
+       kfree(buf2);
        /* let IOP know data has been read */
        arcmsr_iop_message_read(acb);
        return 1;
@@ -1729,10 +1729,10 @@ arcmsr_Read_iop_rqbuffer_data(struct AdapterControlBlock *acb,
        iop_data = (uint8_t __iomem *)prbuffer->data;
        iop_len = readl(&prbuffer->data_len);
        while (iop_len > 0) {
-               pQbuffer = &acb->rqbuffer[acb->rqbuf_lastindex];
+               pQbuffer = &acb->rqbuffer[acb->rqbuf_putIndex];
                *pQbuffer = readb(iop_data);
-               acb->rqbuf_lastindex++;
-               acb->rqbuf_lastindex %= ARCMSR_MAX_QBUFFER;
+               acb->rqbuf_putIndex++;
+               acb->rqbuf_putIndex %= ARCMSR_MAX_QBUFFER;
                iop_data++;
                iop_len--;
        }
@@ -1748,7 +1748,7 @@ static void arcmsr_iop2drv_data_wrote_handle(struct AdapterControlBlock *acb)
 
        spin_lock_irqsave(&acb->rqbuffer_lock, flags);
        prbuffer = arcmsr_get_iop_rqbuffer(acb);
-       buf_empty_len = (acb->rqbuf_lastindex - acb->rqbuf_firstindex - 1) &
+       buf_empty_len = (acb->rqbuf_putIndex - acb->rqbuf_getIndex - 1) &
                (ARCMSR_MAX_QBUFFER - 1);
        if (buf_empty_len >= readl(&prbuffer->data_len)) {
                if (arcmsr_Read_iop_rqbuffer_data(acb, prbuffer) == 0)
@@ -1775,12 +1775,12 @@ static void arcmsr_write_ioctldata2iop_in_DWORD(struct AdapterControlBlock *acb)
                acb->acb_flags &= (~ACB_F_MESSAGE_WQBUFFER_READED);
                pwbuffer = arcmsr_get_iop_wqbuffer(acb);
                iop_data = (uint32_t __iomem *)pwbuffer->data;
-               while ((acb->wqbuf_firstindex != acb->wqbuf_lastindex)
+               while ((acb->wqbuf_getIndex != acb->wqbuf_putIndex)
                        && (allxfer_len < 124)) {
-                       pQbuffer = &acb->wqbuffer[acb->wqbuf_firstindex];
+                       pQbuffer = &acb->wqbuffer[acb->wqbuf_getIndex];
                        *buf1 = *pQbuffer;
-                       acb->wqbuf_firstindex++;
-                       acb->wqbuf_firstindex %= ARCMSR_MAX_QBUFFER;
+                       acb->wqbuf_getIndex++;
+                       acb->wqbuf_getIndex %= ARCMSR_MAX_QBUFFER;
                        buf1++;
                        allxfer_len++;
                }
@@ -1818,12 +1818,12 @@ arcmsr_write_ioctldata2iop(struct AdapterControlBlock *acb)
                acb->acb_flags &= (~ACB_F_MESSAGE_WQBUFFER_READED);
                pwbuffer = arcmsr_get_iop_wqbuffer(acb);
                iop_data = (uint8_t __iomem *)pwbuffer->data;
-               while ((acb->wqbuf_firstindex != acb->wqbuf_lastindex)
+               while ((acb->wqbuf_getIndex != acb->wqbuf_putIndex)
                        && (allxfer_len < 124)) {
-                       pQbuffer = &acb->wqbuffer[acb->wqbuf_firstindex];
+                       pQbuffer = &acb->wqbuffer[acb->wqbuf_getIndex];
                        writeb(*pQbuffer, iop_data);
-                       acb->wqbuf_firstindex++;
-                       acb->wqbuf_firstindex %= ARCMSR_MAX_QBUFFER;
+                       acb->wqbuf_getIndex++;
+                       acb->wqbuf_getIndex %= ARCMSR_MAX_QBUFFER;
                        iop_data++;
                        allxfer_len++;
                }
@@ -1838,9 +1838,9 @@ static void arcmsr_iop2drv_data_read_handle(struct AdapterControlBlock *acb)
 
        spin_lock_irqsave(&acb->wqbuffer_lock, flags);
        acb->acb_flags |= ACB_F_MESSAGE_WQBUFFER_READED;
-       if (acb->wqbuf_firstindex != acb->wqbuf_lastindex)
+       if (acb->wqbuf_getIndex != acb->wqbuf_putIndex)
                arcmsr_write_ioctldata2iop(acb);
-       if (acb->wqbuf_firstindex == acb->wqbuf_lastindex)
+       if (acb->wqbuf_getIndex == acb->wqbuf_putIndex)
                acb->acb_flags |= ACB_F_MESSAGE_WQBUFFER_CLEARED;
        spin_unlock_irqrestore(&acb->wqbuffer_lock, flags);
 }
@@ -2210,14 +2210,14 @@ void arcmsr_clear_iop2drv_rqueue_buffer(struct AdapterControlBlock *acb)
                for (i = 0; i < 15; i++) {
                        if (acb->acb_flags & ACB_F_IOPDATA_OVERFLOW) {
                                acb->acb_flags &= ~ACB_F_IOPDATA_OVERFLOW;
-                               acb->rqbuf_firstindex = 0;
-                               acb->rqbuf_lastindex = 0;
+                               acb->rqbuf_getIndex = 0;
+                               acb->rqbuf_putIndex = 0;
                                arcmsr_iop_message_read(acb);
                                mdelay(30);
-                       } else if (acb->rqbuf_firstindex !=
-                                  acb->rqbuf_lastindex) {
-                               acb->rqbuf_firstindex = 0;
-                               acb->rqbuf_lastindex = 0;
+                       } else if (acb->rqbuf_getIndex !=
+                                  acb->rqbuf_putIndex) {
+                               acb->rqbuf_getIndex = 0;
+                               acb->rqbuf_putIndex = 0;
                                mdelay(30);
                        } else
                                break;
@@ -2256,9 +2256,9 @@ static int arcmsr_iop_message_xfer(struct AdapterControlBlock *acb,
        switch (controlcode) {
        case ARCMSR_MESSAGE_READ_RQBUFFER: {
                unsigned char *ver_addr;
-               uint8_t *pQbuffer, *ptmpQbuffer;
+               uint8_t *ptmpQbuffer;
                uint32_t allxfer_len = 0;
-               ver_addr = kmalloc(1032, GFP_ATOMIC);
+               ver_addr = kmalloc(ARCMSR_API_DATA_BUFLEN, GFP_ATOMIC);
                if (!ver_addr) {
                        retvalue = ARCMSR_MESSAGE_FAIL;
                        pr_info("%s: memory not enough!\n", __func__);
@@ -2266,66 +2266,22 @@ static int arcmsr_iop_message_xfer(struct AdapterControlBlock *acb,
                }
                ptmpQbuffer = ver_addr;
                spin_lock_irqsave(&acb->rqbuffer_lock, flags);
-               if (acb->rqbuf_firstindex != acb->rqbuf_lastindex) {
-                       pQbuffer = &acb->rqbuffer[acb->rqbuf_firstindex];
-                       if (acb->rqbuf_firstindex > acb->rqbuf_lastindex) {
-                               if ((ARCMSR_MAX_QBUFFER -
-                                       acb->rqbuf_firstindex) >= 1032) {
-                                       memcpy(ptmpQbuffer, pQbuffer, 1032);
-                                       acb->rqbuf_firstindex += 1032;
-                                       acb->rqbuf_firstindex %= ARCMSR_MAX_QBUFFER;
-                                       allxfer_len = 1032;
-                               } else {
-                                       if (((ARCMSR_MAX_QBUFFER -
-                                               acb->rqbuf_firstindex) +
-                                               acb->rqbuf_lastindex) > 1032) {
-                                               memcpy(ptmpQbuffer,
-                                                       pQbuffer, ARCMSR_MAX_QBUFFER
-                                                       - acb->rqbuf_firstindex);
-                                               ptmpQbuffer +=
-                                                       ARCMSR_MAX_QBUFFER -
-                                                       acb->rqbuf_firstindex;
-                                               memcpy(ptmpQbuffer,
-                                                       acb->rqbuffer, 1032 -
-                                                       (ARCMSR_MAX_QBUFFER
-                                                       - acb->rqbuf_firstindex));
-                                               acb->rqbuf_firstindex =
-                                                       1032 - (ARCMSR_MAX_QBUFFER
-                                                       - acb->rqbuf_firstindex);
-                                               allxfer_len = 1032;
-                                       } else {
-                                               memcpy(ptmpQbuffer,
-                                                       pQbuffer, ARCMSR_MAX_QBUFFER
-                                                       - acb->rqbuf_firstindex);
-                                               ptmpQbuffer +=
-                                                       ARCMSR_MAX_QBUFFER -
-                                                       acb->rqbuf_firstindex;
-                                               memcpy(ptmpQbuffer,
-                                                       acb->rqbuffer,
-                                                       acb->rqbuf_lastindex);
-                                               allxfer_len = ARCMSR_MAX_QBUFFER
-                                                       - acb->rqbuf_firstindex +
-                                                       acb->rqbuf_lastindex;
-                                               acb->rqbuf_firstindex =
-                                                       acb->rqbuf_lastindex;
-                                       }
-                               }
-                       } else {
-                               if ((acb->rqbuf_lastindex -
-                                       acb->rqbuf_firstindex) > 1032) {
-                                       memcpy(ptmpQbuffer, pQbuffer, 1032);
-                                       acb->rqbuf_firstindex += 1032;
-                                       allxfer_len = 1032;
-                               } else {
-                                       memcpy(ptmpQbuffer, pQbuffer,
-                                               acb->rqbuf_lastindex -
-                                               acb->rqbuf_firstindex);
-                                       allxfer_len = acb->rqbuf_lastindex
-                                               - acb->rqbuf_firstindex;
-                                       acb->rqbuf_firstindex =
-                                               acb->rqbuf_lastindex;
-                               }
+               if (acb->rqbuf_getIndex != acb->rqbuf_putIndex) {
+                       unsigned int tail = acb->rqbuf_getIndex;
+                       unsigned int head = acb->rqbuf_putIndex;
+                       unsigned int cnt_to_end = CIRC_CNT_TO_END(head, tail, ARCMSR_MAX_QBUFFER);
+
+                       allxfer_len = CIRC_CNT(head, tail, ARCMSR_MAX_QBUFFER);
+                       if (allxfer_len > ARCMSR_API_DATA_BUFLEN)
+                               allxfer_len = ARCMSR_API_DATA_BUFLEN;
+
+                       if (allxfer_len <= cnt_to_end)
+                               memcpy(ptmpQbuffer, acb->rqbuffer + tail, allxfer_len);
+                       else {
+                               memcpy(ptmpQbuffer, acb->rqbuffer + tail, cnt_to_end);
+                               memcpy(ptmpQbuffer + cnt_to_end, acb->rqbuffer, allxfer_len - cnt_to_end);
                        }
+                       acb->rqbuf_getIndex = (acb->rqbuf_getIndex + allxfer_len) % ARCMSR_MAX_QBUFFER;
                }
                memcpy(pcmdmessagefld->messagedatabuffer, ver_addr,
                        allxfer_len);
@@ -2349,9 +2305,9 @@ static int arcmsr_iop_message_xfer(struct AdapterControlBlock *acb,
        }
        case ARCMSR_MESSAGE_WRITE_WQBUFFER: {
                unsigned char *ver_addr;
-               int32_t my_empty_len, user_len, wqbuf_firstindex, wqbuf_lastindex;
+               int32_t user_len, cnt2end;
                uint8_t *pQbuffer, *ptmpuserbuffer;
-               ver_addr = kmalloc(1032, GFP_ATOMIC);
+               ver_addr = kmalloc(ARCMSR_API_DATA_BUFLEN, GFP_ATOMIC);
                if (!ver_addr) {
                        retvalue = ARCMSR_MESSAGE_FAIL;
                        goto message_out;
@@ -2361,9 +2317,7 @@ static int arcmsr_iop_message_xfer(struct AdapterControlBlock *acb,
                memcpy(ptmpuserbuffer,
                        pcmdmessagefld->messagedatabuffer, user_len);
                spin_lock_irqsave(&acb->wqbuffer_lock, flags);
-               wqbuf_lastindex = acb->wqbuf_lastindex;
-               wqbuf_firstindex = acb->wqbuf_firstindex;
-               if (wqbuf_lastindex != wqbuf_firstindex) {
+               if (acb->wqbuf_putIndex != acb->wqbuf_getIndex) {
                        struct SENSE_DATA *sensebuffer =
                                (struct SENSE_DATA *)cmd->sense_buffer;
                        arcmsr_write_ioctldata2iop(acb);
@@ -2375,48 +2329,22 @@ static int arcmsr_iop_message_xfer(struct AdapterControlBlock *acb,
                        sensebuffer->Valid = 1;
                        retvalue = ARCMSR_MESSAGE_FAIL;
                } else {
-                       my_empty_len = (wqbuf_firstindex - wqbuf_lastindex - 1)
-                               & (ARCMSR_MAX_QBUFFER - 1);
-                       if (my_empty_len >= user_len) {
-                               while (user_len > 0) {
-                                       pQbuffer = &acb->wqbuffer[acb->wqbuf_lastindex];
-                                       if ((acb->wqbuf_lastindex + user_len)
-                                               > ARCMSR_MAX_QBUFFER) {
-                                               memcpy(pQbuffer, ptmpuserbuffer,
-                                                       ARCMSR_MAX_QBUFFER -
-                                                       acb->wqbuf_lastindex);
-                                               ptmpuserbuffer +=
-                                                       (ARCMSR_MAX_QBUFFER
-                                                       - acb->wqbuf_lastindex);
-                                               user_len -= (ARCMSR_MAX_QBUFFER
-                                                       - acb->wqbuf_lastindex);
-                                               acb->wqbuf_lastindex = 0;
-                                       } else {
-                                               memcpy(pQbuffer, ptmpuserbuffer,
-                                                       user_len);
-                                               acb->wqbuf_lastindex += user_len;
-                                               acb->wqbuf_lastindex %=
-                                                       ARCMSR_MAX_QBUFFER;
-                                               user_len = 0;
-                                       }
-                               }
-                               if (acb->acb_flags &
-                                       ACB_F_MESSAGE_WQBUFFER_CLEARED) {
-                                       acb->acb_flags &=
+                       pQbuffer = &acb->wqbuffer[acb->wqbuf_putIndex];
+                       cnt2end = ARCMSR_MAX_QBUFFER - acb->wqbuf_putIndex;
+                       if (user_len > cnt2end) {
+                               memcpy(pQbuffer, ptmpuserbuffer, cnt2end);
+                               ptmpuserbuffer += cnt2end;
+                               user_len -= cnt2end;
+                               acb->wqbuf_putIndex = 0;
+                               pQbuffer = acb->wqbuffer;
+                       }
+                       memcpy(pQbuffer, ptmpuserbuffer, user_len);
+                       acb->wqbuf_putIndex += user_len;
+                       acb->wqbuf_putIndex %= ARCMSR_MAX_QBUFFER;
+                       if (acb->acb_flags & ACB_F_MESSAGE_WQBUFFER_CLEARED) {
+                               acb->acb_flags &=
                                                ~ACB_F_MESSAGE_WQBUFFER_CLEARED;
-                                       arcmsr_write_ioctldata2iop(acb);
-                               }
-                       } else {
-                               struct SENSE_DATA *sensebuffer =
-                                       (struct SENSE_DATA *)cmd->sense_buffer;
-                               /* has error report sensedata */
-                               sensebuffer->ErrorCode =
-                                       SCSI_SENSE_CURRENT_ERRORS;
-                               sensebuffer->SenseKey = ILLEGAL_REQUEST;
-                               sensebuffer->AdditionalSenseLength = 0x0A;
-                               sensebuffer->AdditionalSenseCode = 0x20;
-                               sensebuffer->Valid = 1;
-                               retvalue = ARCMSR_MESSAGE_FAIL;
+                               arcmsr_write_ioctldata2iop(acb);
                        }
                }
                spin_unlock_irqrestore(&acb->wqbuffer_lock, flags);
@@ -2435,8 +2363,8 @@ static int arcmsr_iop_message_xfer(struct AdapterControlBlock *acb,
                arcmsr_clear_iop2drv_rqueue_buffer(acb);
                spin_lock_irqsave(&acb->rqbuffer_lock, flags);
                acb->acb_flags |= ACB_F_MESSAGE_RQBUFFER_CLEARED;
-               acb->rqbuf_firstindex = 0;
-               acb->rqbuf_lastindex = 0;
+               acb->rqbuf_getIndex = 0;
+               acb->rqbuf_putIndex = 0;
                memset(pQbuffer, 0, ARCMSR_MAX_QBUFFER);
                spin_unlock_irqrestore(&acb->rqbuffer_lock, flags);
                if (acb->fw_flag == FW_DEADLOCK)
@@ -2452,8 +2380,8 @@ static int arcmsr_iop_message_xfer(struct AdapterControlBlock *acb,
                spin_lock_irqsave(&acb->wqbuffer_lock, flags);
                acb->acb_flags |= (ACB_F_MESSAGE_WQBUFFER_CLEARED |
                        ACB_F_MESSAGE_WQBUFFER_READED);
-               acb->wqbuf_firstindex = 0;
-               acb->wqbuf_lastindex = 0;
+               acb->wqbuf_getIndex = 0;
+               acb->wqbuf_putIndex = 0;
                memset(pQbuffer, 0, ARCMSR_MAX_QBUFFER);
                spin_unlock_irqrestore(&acb->wqbuffer_lock, flags);
                if (acb->fw_flag == FW_DEADLOCK)
@@ -2469,16 +2397,16 @@ static int arcmsr_iop_message_xfer(struct AdapterControlBlock *acb,
                arcmsr_clear_iop2drv_rqueue_buffer(acb);
                spin_lock_irqsave(&acb->rqbuffer_lock, flags);
                acb->acb_flags |= ACB_F_MESSAGE_RQBUFFER_CLEARED;
-               acb->rqbuf_firstindex = 0;
-               acb->rqbuf_lastindex = 0;
+               acb->rqbuf_getIndex = 0;
+               acb->rqbuf_putIndex = 0;
                pQbuffer = acb->rqbuffer;
                memset(pQbuffer, 0, sizeof(struct QBUFFER));
                spin_unlock_irqrestore(&acb->rqbuffer_lock, flags);
                spin_lock_irqsave(&acb->wqbuffer_lock, flags);
                acb->acb_flags |= (ACB_F_MESSAGE_WQBUFFER_CLEARED |
                        ACB_F_MESSAGE_WQBUFFER_READED);
-               acb->wqbuf_firstindex = 0;
-               acb->wqbuf_lastindex = 0;
+               acb->wqbuf_getIndex = 0;
+               acb->wqbuf_putIndex = 0;
                pQbuffer = acb->wqbuffer;
                memset(pQbuffer, 0, sizeof(struct QBUFFER));
                spin_unlock_irqrestore(&acb->wqbuffer_lock, flags);