[PATCH 6/7] Convert sg to block layer helpers

michaelc
2007-03-04T18:31:44Z

Convert sg to block layer helpers. I have tested with sg3_utils and
sg_utils. I have tested the mmap, iovec, dio and indirect IO paths,
by running those tools and the example programs against software
iscsi which does not support clustering, scsi_debug which has
a large segment size limit, and libata.
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
---
drivers/scsi/sg.c | 1004 +++++++++++++----------------------------------------
1 files changed, 245 insertions(+), 759 deletions(-)

diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index 81e3bc7..53cc140 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -67,7 +67,6 @@ static void sg_proc_cleanup(void);
#endif

#define SG_ALLOW_DIO_DEF 0
-#define SG_ALLOW_DIO_CODE /* compile out by commenting this define */

#define SG_MAX_DEVS 32768

@@ -94,9 +93,6 @@ int sg_big_buff = SG_DEF_RESERVED_SIZE;
static int def_reserved_size = -1; /* picks up init parameter */
static int sg_allow_dio = SG_ALLOW_DIO_DEF;

-static int scatter_elem_sz = SG_SCATTER_SZ;
-static int scatter_elem_sz_prev = SG_SCATTER_SZ;
-
#define SG_SECTOR_SZ 512
#define SG_SECTOR_MSK (SG_SECTOR_SZ - 1)

@@ -115,12 +111,9 @@ static struct class_interface sg_interfa

typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
- unsigned short sglist_len; /* size of malloc'd scatter-gather list ++ */
unsigned bufflen; /* Size of (aggregate) data buffer */
- unsigned b_malloc_len; /* actual len malloc'ed in buffer */
- struct scatterlist *buffer;/* scatter list */
- char dio_in_use; /* 0->indirect IO (or mmap), 1->dio */
unsigned char cmd_opcode; /* first byte of command */
+ struct bio_reserve_buf *rbuf; /* reserve memory */
} Sg_scatter_hold;

struct sg_device; /* forward declarations */
@@ -132,6 +125,8 @@ typedef struct sg_request { /* SG_MAX_QU
Sg_scatter_hold data; /* hold buffer, perhaps scatter list */
sg_io_hdr_t header; /* scsi command+info, see <scsi/sg.h> */
unsigned char sense_b[SCSI_SENSE_BUFFERSIZE];
+ struct request *request;
+ struct bio *bio; /* ptr to bio for later unmapping */
char res_used; /* 1 -> using reserve buffer, 0 -> not ... */
char orphan; /* 1 -> drop on sight, 0 -> normal */
char sg_io_owned; /* 1 -> packet belongs to SG_IO */
@@ -146,7 +141,6 @@ typedef struct sg_fd { /* holds the sta
int timeout; /* defaults to SG_DEFAULT_TIMEOUT */
int timeout_user; /* defaults to SG_DEFAULT_TIMEOUT_USER */
Sg_scatter_hold reserve; /* buffer held for this file descriptor */
- unsigned save_scat_len; /* original length of trunc. scat. element */
Sg_request *headrp; /* head of request slist, NULL->empty */
struct fasync_struct *async_qp; /* used by asynchronous notification */
Sg_request req_arr[SG_MAX_QUEUE]; /* used as singly-linked list */
@@ -173,38 +167,24 @@ typedef struct sg_device { /* holds the

static int sg_fasync(int fd, struct file *filp, int mode);
/* tasklet or soft irq callback */
-static void sg_cmd_done(void *data, char *sense, int result, int resid);
-static int sg_start_req(Sg_request * srp);
+static void sg_cmd_done(struct request *rq, int uptodate);
+static int sg_setup_req(Sg_request * srp);
static void sg_finish_rem_req(Sg_request * srp);
-static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
-static int sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp,
- int tablesize);
static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
Sg_request * srp);
static ssize_t sg_new_write(Sg_fd * sfp, const char __user *buf, size_t count,
int blocking, int read_only, Sg_request ** o_srp);
static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
unsigned char *cmnd, int timeout, int blocking);
-static int sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind,
- int wr_xf, int *countp, unsigned char __user **up);
-static int sg_write_xfer(Sg_request * srp);
static int sg_read_xfer(Sg_request * srp);
-static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
-static void sg_remove_scat(Sg_scatter_hold * schp);
-static void sg_build_reserve(Sg_fd * sfp, int req_size);
-static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
-static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
-static struct page *sg_page_malloc(int rqSz, int lowDma, int *retSzp);
-static void sg_page_free(struct page *page, int size);
+static int sg_build_reserve(Sg_fd * sfp, int req_size);
static Sg_fd *sg_add_sfp(Sg_device * sdp, int dev);
static int sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
static void __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
static Sg_request *sg_add_request(Sg_fd * sfp);
static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
-static int sg_res_in_use(Sg_fd * sfp);
static int sg_allow_access(unsigned char opcode, char dev_type);
-static int sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len);
static Sg_device *sg_get_dev(int dev);
#ifdef CONFIG_SCSI_PROC_FS
static int sg_last_dev(void);
@@ -305,6 +285,16 @@ sg_open(struct inode *inode, struct file
return retval;
}

+static void sg_cleanup_transfer(struct sg_request *srp)
+{
+ struct sg_fd *sfp = srp->parentfp;
+
+ srp->bio = NULL;
+ if (srp->res_used)
+ bio_release_reserve_buf(sfp->reserve.rbuf);
+ srp->res_used = 0;
+}
+
/* Following function was formerly called 'sg_close' */
static int
sg_release(struct inode *inode, struct file *filp)
@@ -464,7 +454,9 @@ sg_read(struct file *filp, char __user *
if (count > old_hdr->reply_len)
count = old_hdr->reply_len;
if (count > SZ_SG_HEADER) {
- if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
+ retval = blk_rq_complete_transfer(srp->bio, buf, count);
+ sg_cleanup_transfer(srp);
+ if (retval) {
retval = -EFAULT;
goto free_old_hdr;
}
@@ -650,18 +642,13 @@ sg_new_write(Sg_fd * sfp, const char __u
return -ENOSYS;
}
if (hp->flags & SG_FLAG_MMAP_IO) {
- if (hp->dxfer_len > sfp->reserve.bufflen) {
- sg_remove_request(sfp, srp);
- return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
- }
+ /*
+ * the call to mmap will have claimed the reserve buffer
+ */
if (hp->flags & SG_FLAG_DIRECT_IO) {
sg_remove_request(sfp, srp);
return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
}
- if (sg_res_in_use(sfp)) {
- sg_remove_request(sfp, srp);
- return -EBUSY; /* reserve buffer already being used */
- }
}
ul_timeout = msecs_to_jiffies(srp->header.timeout);
timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
@@ -694,9 +681,11 @@ static int
sg_common_write(Sg_fd * sfp, Sg_request * srp,
unsigned char *cmnd, int timeout, int blocking)
{
- int k, data_dir;
+ int k;
Sg_device *sdp = sfp->parentdp;
sg_io_hdr_t *hp = &srp->header;
+ struct request_queue *q = sdp->device->request_queue;
+ struct request *rq;

srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
hp->status = 0;
@@ -706,54 +695,46 @@ sg_common_write(Sg_fd * sfp, Sg_request
hp->host_status = 0;
hp->driver_status = 0;
hp->resid = 0;
+
SCSI_LOG_TIMEOUT(4, printk("sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n",
(int) cmnd[0], (int) hp->cmd_len));

- if ((k = sg_start_req(srp))) {
+ rq = blk_get_request(q, hp->dxfer_direction == SG_DXFER_TO_DEV,
+ GFP_NOIO);
+ if (!rq) {
+ SCSI_LOG_TIMEOUT(1, printk("sg_common_write: Could "
+ "not allocate request\n"));
+ return -ENOMEM;
+ }
+ srp->request = rq;
+
+ memset(srp->sense_b, 0, SCSI_SENSE_BUFFERSIZE);
+ rq->sense = srp->sense_b;
+ rq->sense_len = 0;
+ rq->cmd_len = hp->cmd_len;
+ memcpy(rq->cmd, cmnd, rq->cmd_len);
+ rq->timeout = timeout;
+ rq->retries = SG_DEFAULT_RETRIES;
+ rq->cmd_type = REQ_TYPE_BLOCK_PC;
+ rq->cmd_flags |= REQ_QUIET;
+ rq->end_io_data = srp;
+
+ if ((k = sg_setup_req(srp))) {
SCSI_LOG_TIMEOUT(1, printk("sg_common_write: start_req err=%d\n", k));
sg_finish_rem_req(srp);
return k; /* probably out of space --> ENOMEM */
}
- if ((k = sg_write_xfer(srp))) {
- SCSI_LOG_TIMEOUT(1, printk("sg_common_write: write_xfer, bad address\n"));
- sg_finish_rem_req(srp);
- return k;
- }
+ /* must save for later unmapping */
+ srp->bio = rq->bio;
+
if (sdp->detached) {
sg_finish_rem_req(srp);
return -ENODEV;
}

- switch (hp->dxfer_direction) {
- case SG_DXFER_TO_FROM_DEV:
- case SG_DXFER_FROM_DEV:
- data_dir = DMA_FROM_DEVICE;
- break;
- case SG_DXFER_TO_DEV:
- data_dir = DMA_TO_DEVICE;
- break;
- case SG_DXFER_UNKNOWN:
- data_dir = DMA_BIDIRECTIONAL;
- break;
- default:
- data_dir = DMA_NONE;
- break;
- }
hp->duration = jiffies_to_msecs(jiffies);
-/* Now send everything of to mid-level. The next time we hear about this
- packet is when sg_cmd_done() is called (i.e. a callback). */
- if (scsi_execute_async(sdp->device, cmnd, hp->cmd_len, data_dir, srp->data.buffer,
- hp->dxfer_len, srp->data.k_use_sg, timeout,
- SG_DEFAULT_RETRIES, srp, sg_cmd_done,
- GFP_ATOMIC)) {
- SCSI_LOG_TIMEOUT(1, printk("sg_common_write: scsi_execute_async failed\n"));
- /*
- * most likely out of mem, but could also be a bad map
- */
- sg_finish_rem_req(srp);
- return -ENOMEM;
- } else
- return 0;
+ blk_execute_rq_nowait(q, NULL, rq, 1, sg_cmd_done);
+ return 0;
}

static int
@@ -842,14 +823,13 @@ sg_ioctl(struct inode *inode, struct fil
result = get_user(val, ip);
if (result)
return result;
- if (val) {
+ if (val)
+ /*
+ * We should always be allocated mem from the right
+ * limit, so maybe this should always be zero?.
+ */
sfp->low_dma = 1;
- if ((0 == sfp->low_dma) && (0 == sg_res_in_use(sfp))) {
- val = (int) sfp->reserve.bufflen;
- sg_remove_scat(&sfp->reserve);
- sg_build_reserve(sfp, val);
- }
- } else {
+ else {
if (sdp->detached)
return -ENODEV;
sfp->low_dma = sdp->device->host->unchecked_isa_dma;
@@ -917,13 +897,7 @@ sg_ioctl(struct inode *inode, struct fil
return result;
if (val < 0)
return -EINVAL;
- if (val != sfp->reserve.bufflen) {
- if (sg_res_in_use(sfp) || sfp->mmap_called)
- return -EBUSY;
- sg_remove_scat(&sfp->reserve);
- sg_build_reserve(sfp, val);
- }
- return 0;
+ return sg_build_reserve(sfp, val);
case SG_GET_RESERVED_SIZE:
val = (int) sfp->reserve.bufflen;
return put_user(val, ip);
@@ -1146,38 +1120,11 @@ static struct page *
sg_vma_nopage(struct vm_area_struct *vma, unsigned long addr, int *type)
{
Sg_fd *sfp;
- struct page *page = NOPAGE_SIGBUS;
- unsigned long offset, len, sa;
- Sg_scatter_hold *rsv_schp;
- struct scatterlist *sg;
- int k;

if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
- return page;
- rsv_schp = &sfp->reserve;
- offset = addr - vma->vm_start;
- if (offset >= rsv_schp->bufflen)
- return page;
- SCSI_LOG_TIMEOUT(3, printk("sg_vma_nopage: offset=%lu, scatg=%d\n",
- offset, rsv_schp->k_use_sg));
- sg = rsv_schp->buffer;
- sa = vma->vm_start;
- for (k = 0; (k < rsv_schp->k_use_sg) && (sa < vma->vm_end);
- ++k, ++sg) {
- len = vma->vm_end - sa;
- len = (len < sg->length) ? len : sg->length;
- if (offset < len) {
- page = virt_to_page(page_address(sg->page) + offset);
- get_page(page); /* increment page count */
- break;
- }
- sa += len;
- offset -= len;
- }
+ return NOPAGE_SIGBUS;

- if (type)
- *type = VM_FAULT_MINOR;
- return page;
+ return blk_rq_vma_nopage(sfp->reserve.rbuf, vma, addr, type);
}

static struct vm_operations_struct sg_mmap_vm_ops = {
@@ -1188,30 +1135,21 @@ static int
sg_mmap(struct file *filp, struct vm_area_struct *vma)
{
Sg_fd *sfp;
- unsigned long req_sz, len, sa;
- Sg_scatter_hold *rsv_schp;
- int k;
- struct scatterlist *sg;
+ int res;

if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
return -ENXIO;
- req_sz = vma->vm_end - vma->vm_start;
- SCSI_LOG_TIMEOUT(3, printk("sg_mmap starting, vm_start=%p, len=%d\n",
- (void *) vma->vm_start, (int) req_sz));
- if (vma->vm_pgoff)
- return -EINVAL; /* want no offset */
- rsv_schp = &sfp->reserve;
- if (req_sz > rsv_schp->bufflen)
- return -ENOMEM; /* cannot map more than reserved buffer */
-
- sa = vma->vm_start;
- sg = rsv_schp->buffer;
- for (k = 0; (k < rsv_schp->k_use_sg) && (sa < vma->vm_end);
- ++k, ++sg) {
- len = vma->vm_end - sa;
- len = (len < sg->length) ? len : sg->length;
- sa += len;
- }
+ SCSI_LOG_TIMEOUT(3, printk("sg_mmap starting, vm_start=%p\n",
+ (void *) vma->vm_start));
+
+ /*
+ * This only checks that we can execute the op.
+ * We do not reserve the buffer and build the request
+ * until it is sent down through the write.
+ */
+ res = blk_rq_mmap(sfp->reserve.rbuf, vma);
+ if (res)
+ return res;

sfp->mmap_called = 1;
vma->vm_flags |= VM_RESERVED;
@@ -1221,53 +1159,51 @@ sg_mmap(struct file *filp, struct vm_are
}

/* This function is a "bottom half" handler that is called by the
- * mid level when a command is completed (or has failed). */
+ * block level when a command is completed (or has failed). */
static void
-sg_cmd_done(void *data, char *sense, int result, int resid)
+sg_cmd_done(struct request *rq, int uptodate)
{
- Sg_request *srp = data;
+ Sg_request *srp = rq->end_io_data;
Sg_device *sdp = NULL;
Sg_fd *sfp;
unsigned long iflags;
unsigned int ms;

if (NULL == srp) {
- printk(KERN_ERR "sg_cmd_done: NULL request\n");
+ __blk_put_request(rq->q, rq);
return;
}
sfp = srp->parentfp;
if (sfp)
sdp = sfp->parentdp;
if ((NULL == sdp) || sdp->detached) {
- printk(KERN_INFO "sg_cmd_done: device detached\n");
+ __blk_put_request(rq->q, rq);
return;
}

-
SCSI_LOG_TIMEOUT(4, printk("sg_cmd_done: %s, pack_id=%d, res=0x%x\n",
- sdp->disk->disk_name, srp->header.pack_id, result));
- srp->header.resid = resid;
+ sdp->disk->disk_name, srp->header.pack_id, rq->errors));
+ srp->header.resid = rq->data_len;
ms = jiffies_to_msecs(jiffies);
srp->header.duration = (ms > srp->header.duration) ?
(ms - srp->header.duration) : 0;
- if (0 != result) {
+ if (0 != rq->errors) {
struct scsi_sense_hdr sshdr;

- memcpy(srp->sense_b, sense, sizeof (srp->sense_b));
- srp->header.status = 0xff & result;
- srp->header.masked_status = status_byte(result);
- srp->header.msg_status = msg_byte(result);
- srp->header.host_status = host_byte(result);
- srp->header.driver_status = driver_byte(result);
+ srp->header.status = 0xff & rq->errors;
+ srp->header.masked_status = status_byte(rq->errors);
+ srp->header.msg_status = msg_byte(rq->errors);
+ srp->header.host_status = host_byte(rq->errors);
+ srp->header.driver_status = driver_byte(rq->errors);
if ((sdp->sgdebug > 0) &&
((CHECK_CONDITION == srp->header.masked_status) ||
(COMMAND_TERMINATED == srp->header.masked_status)))
- __scsi_print_sense("sg_cmd_done", sense,
- SCSI_SENSE_BUFFERSIZE);
+ __scsi_print_sense("sg_cmd_done", rq->sense,
+ rq->sense_len);

/* Following if statement is a patch supplied by Eric Youngdale */
- if (driver_byte(result) != 0
- && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
+ if (driver_byte(rq->errors) != 0
+ && scsi_normalize_sense(rq->sense, rq->sense_len, &sshdr)
&& !scsi_sense_is_deferred(&sshdr)
&& sshdr.sense_key == UNIT_ATTENTION
&& sdp->device->removable) {
@@ -1276,12 +1212,14 @@ sg_cmd_done(void *data, char *sense, int
sdp->device->changed = 1;
}
}
+
+ srp->request = NULL;
+ __blk_put_request(rq->q, rq);
/* Rely on write phase to clean out srp status values, so no "else" */

if (sfp->closed) { /* whoops this fd already released, cleanup */
SCSI_LOG_TIMEOUT(1, printk("sg_cmd_done: already closed, freeing ...\n"));
sg_finish_rem_req(srp);
- srp = NULL;
if (NULL == sfp->headrp) {
SCSI_LOG_TIMEOUT(1, printk("sg_cmd_done: already closed, final cleanup\n"));
if (0 == sg_remove_sfp(sdp, sfp)) { /* device still present */
@@ -1292,10 +1230,8 @@ sg_cmd_done(void *data, char *sense, int
} else if (srp && srp->orphan) {
if (sfp->keep_orphan)
srp->sg_io_owned = 0;
- else {
+ else
sg_finish_rem_req(srp);
- srp = NULL;
- }
}
if (sfp && srp) {
/* Now wake up any sg_read() that is waiting for this packet. */
@@ -1540,7 +1476,6 @@ sg_remove(struct class_device *cl_dev, s
msleep(10); /* dirty detach so delay device destruction */
}

-module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
module_param_named(def_reserved_size, def_reserved_size, int,
S_IRUGO | S_IWUSR);
module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
@@ -1551,8 +1486,6 @@ MODULE_LICENSE("GPL");
MODULE_VERSION(SG_VERSION_STR);
MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);

-MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
- "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");

@@ -1561,10 +1494,6 @@ init_sg(void)
{
int rc;

- if (scatter_elem_sz < PAGE_SIZE) {
- scatter_elem_sz = PAGE_SIZE;
- scatter_elem_sz_prev = scatter_elem_sz;
- }
if (def_reserved_size >= 0)
sg_big_buff = def_reserved_size;
else
@@ -1610,602 +1539,218 @@ #endif /* CONFIG_SCSI_PROC_FS */
}

static int
-sg_start_req(Sg_request * srp)
+sg_setup_req(Sg_request * srp)
{
- int res;
+ struct request *rq = srp->request;
Sg_fd *sfp = srp->parentfp;
sg_io_hdr_t *hp = &srp->header;
+ struct sg_iovec *u_iov;
int dxfer_len = (int) hp->dxfer_len;
int dxfer_dir = hp->dxfer_direction;
- Sg_scatter_hold *req_schp = &srp->data;
- Sg_scatter_hold *rsv_schp = &sfp->reserve;
-
- SCSI_LOG_TIMEOUT(4, printk("sg_start_req: dxfer_len=%d\n", dxfer_len));
- if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
- return 0;
- if (sg_allow_dio && (hp->flags & SG_FLAG_DIRECT_IO) &&
- (dxfer_dir != SG_DXFER_UNKNOWN) && (0 == hp->iovec_count) &&
- (!sfp->parentdp->device->host->unchecked_isa_dma)) {
- res = sg_build_direct(srp, sfp, dxfer_len);
- if (res <= 0) /* -ve -> error, 0 -> done, 1 -> try indirect */
- return res;
- }
- if ((!sg_res_in_use(sfp)) && (dxfer_len <= rsv_schp->bufflen))
- sg_link_reserve(sfp, srp, dxfer_len);
- else {
- res = sg_build_indirect(req_schp, sfp, dxfer_len);
- if (res) {
- sg_remove_scat(req_schp);
- return res;
- }
- }
- return 0;
-}
-
-static void
-sg_finish_rem_req(Sg_request * srp)
-{
- Sg_fd *sfp = srp->parentfp;
- Sg_scatter_hold *req_schp = &srp->data;
-
- SCSI_LOG_TIMEOUT(4, printk("sg_finish_rem_req: res_used=%d\n", (int) srp->res_used));
- if (srp->res_used)
- sg_unlink_reserve(sfp, srp);
- else
- sg_remove_scat(req_schp);
- sg_remove_request(sfp, srp);
-}
-
-static int
-sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
-{
- int sg_bufflen = tablesize * sizeof(struct scatterlist);
- gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
-
- /*
- * TODO: test without low_dma, we should not need it since
- * the block layer will bounce the buffer for us
- *
- * XXX(hch): we shouldn't need GFP_DMA for the actual S/G list.
- */
- if (sfp->low_dma)
- gfp_flags |= GFP_DMA;
- schp->buffer = kzalloc(sg_bufflen, gfp_flags);
- if (!schp->buffer)
- return -ENOMEM;
- schp->sglist_len = sg_bufflen;
- return tablesize; /* number of scat_gath elements allocated */
-}
-
-#ifdef SG_ALLOW_DIO_CODE
-/* vvvvvvvv following code borrowed from st driver's direct IO vvvvvvvvv */
- /* TODO: hopefully we can use the generic block layer code */
-
-/* Pin down user pages and put them into a scatter gather list. Returns <= 0 if
- - mapping of all pages not successful
- (i.e., either completely successful or fails)
-*/
-static int
-st_map_user_pages(struct scatterlist *sgl, const unsigned int max_pages,
- unsigned long uaddr, size_t count, int rw)
-{
- unsigned long end = (uaddr + count + PAGE_SIZE - 1) >> PAGE_SHIFT;
- unsigned long start = uaddr >> PAGE_SHIFT;
- const int nr_pages = end - start;
- int res, i, j;
- struct page **pages;
-
- /* User attempted Overflow! */
- if ((uaddr + count) < uaddr)
- return -EINVAL;
+ int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
+ int res = 0, num_xfer = 0, size;
+ struct bio_reserve_buf *rbuf = NULL;

- /* Too big */
- if (nr_pages > max_pages)
- return -ENOMEM;
+ SCSI_LOG_TIMEOUT(4, printk("sg_setup_req: dxfer_len=%d\n", dxfer_len));

- /* Hmm? */
- if (count == 0)
+ /* no transfer */
+ if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE) ||
+ (new_interface && (SG_FLAG_NO_DXFER & hp->flags)))
return 0;

- if ((pages = kmalloc(max_pages * sizeof(*pages), GFP_ATOMIC)) == NULL)
- return -ENOMEM;
-
- /* Try to fault in all of the necessary pages */
- down_read(&current->mm->mmap_sem);
- /* rw==READ means read from drive, write into memory area */
- res = get_user_pages(
- current,
- current->mm,
- uaddr,
- nr_pages,
- rw == READ,
- 0, /* don't force */
- pages,
- NULL);
- up_read(&current->mm->mmap_sem);
-
- /* Errors and no page mapped should return here */
- if (res < nr_pages)
- goto out_unmap;
-
- for (i=0; i < nr_pages; i++) {
- /* FIXME: flush superflous for rw==READ,
- * probably wrong function for rw==WRITE
- */
- flush_dcache_page(pages[i]);
- /* ?? Is locking needed? I don't think so */
- /* if (TestSetPageLocked(pages[i]))
- goto out_unlock; */
- }
+ /* mmap */
+ if (new_interface && (SG_FLAG_MMAP_IO & hp->flags)) {
+ res = bio_claim_reserve_buf(sfp->reserve.rbuf, dxfer_len);
+ if (res)
+ return res;
+ rbuf = sfp->reserve.rbuf;

- sgl[0].page = pages[0];
- sgl[0].offset = uaddr & ~PAGE_MASK;
- if (nr_pages > 1) {
- sgl[0].length = PAGE_SIZE - sgl[0].offset;
- count -= sgl[0].length;
- for (i=1; i < nr_pages ; i++) {
- sgl[i].page = pages[i];
- sgl[i].length = count < PAGE_SIZE ? count : PAGE_SIZE;
- count -= PAGE_SIZE;
- }
- }
- else {
- sgl[0].length = count;
+ res = blk_rq_setup_buffer(rq, NULL, dxfer_len, rbuf);
+ if (res)
+ goto release_rbuf;
+ goto done;
}

- kfree(pages);
- return nr_pages;
-
- out_unmap:
- if (res > 0) {
- for (j=0; j < res; j++)
- page_cache_release(pages[j]);
- res = 0;
+ /* dio */
+ if (sg_allow_dio && (hp->flags & SG_FLAG_DIRECT_IO) &&
+ (dxfer_dir != SG_DXFER_UNKNOWN) && (0 == hp->iovec_count) &&
+ (!sfp->parentdp->device->host->unchecked_isa_dma)) {
+ res = blk_rq_map_user(rq->q, rq, hp->dxferp, dxfer_len);
+ if (!res)
+ return 0;
}
- kfree(pages);
- return res;
-}
-
-
-/* And unmap them... */
-static int
-st_unmap_user_pages(struct scatterlist *sgl, const unsigned int nr_pages,
- int dirtied)
-{
- int i;

- for (i=0; i < nr_pages; i++) {
- struct page *page = sgl[i].page;
-
- if (dirtied)
- SetPageDirty(page);
- /* unlock_page(page); */
- /* FIXME: cache flush missing for rw==READ
- * FIXME: call the correct reference counting function
- */
- page_cache_release(page);
+ /* copy */
+ /* old interface put SG_DXFER_TO_DEV/SG_DXFER_TO_FROM_DEV in flags */
+ if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_TO_DEV == dxfer_dir) ||
+ (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
+ num_xfer = (int) (new_interface ? hp->dxfer_len : hp->flags);
+ if (num_xfer > dxfer_len)
+ num_xfer = dxfer_len;
}

- return 0;
-}
-
-/* ^^^^^^^^ above code borrowed from st driver's direct IO ^^^^^^^^^ */
-#endif
+ SCSI_LOG_TIMEOUT(4, printk("sg_setup_req: Try xfer num_xfer=%d, "
+ "iovec_count=%d\n", dxfer_len, hp->iovec_count));

+ /* check if reserve buf is available and correct size */
+ if (!bio_claim_reserve_buf(sfp->reserve.rbuf, dxfer_len))
+ rbuf = sfp->reserve.rbuf;

-/* Returns: -ve -> error, 0 -> done, 1 -> try indirect */
-static int
-sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len)
-{
-#ifdef SG_ALLOW_DIO_CODE
- sg_io_hdr_t *hp = &srp->header;
- Sg_scatter_hold *schp = &srp->data;
- int sg_tablesize = sfp->parentdp->sg_tablesize;
- int mx_sc_elems, res;
- struct scsi_device *sdev = sfp->parentdp->device;
+ if (!hp->iovec_count) {
+ struct sg_iovec iov;

- if (((unsigned long)hp->dxferp &
- queue_dma_alignment(sdev->request_queue)) != 0)
- return 1;
+ iov.iov_base = hp->dxferp;
+ iov.iov_len = num_xfer;

- mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
- if (mx_sc_elems <= 0) {
- return 1;
- }
- res = st_map_user_pages(schp->buffer, mx_sc_elems,
- (unsigned long)hp->dxferp, dxfer_len,
- (SG_DXFER_TO_DEV == hp->dxfer_direction) ? 1 : 0);
- if (res <= 0) {
- sg_remove_scat(schp);
- return 1;
+ res = blk_rq_copy_user_iov(rq, &iov, 1, dxfer_len, rbuf);
+ if (res)
+ goto release_rbuf;
+ goto done;
}
- schp->k_use_sg = res;
- schp->dio_in_use = 1;
- hp->info |= SG_INFO_DIRECT_IO;
- return 0;
-#else
- return 1;
-#endif
-}

-static int
-sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
-{
- struct scatterlist *sg;
- int ret_sz = 0, k, rem_sz, num, mx_sc_elems;
- int sg_tablesize = sfp->parentdp->sg_tablesize;
- int blk_size = buff_size;
- struct page *p = NULL;
-
- if ((blk_size < 0) || (!sfp))
- return -EFAULT;
- if (0 == blk_size)
- ++blk_size; /* don't know why */
-/* round request up to next highest SG_SECTOR_SZ byte boundary */
- blk_size = (blk_size + SG_SECTOR_MSK) & (~SG_SECTOR_MSK);
- SCSI_LOG_TIMEOUT(4, printk("sg_build_indirect: buff_size=%d, blk_size=%d\n",
- buff_size, blk_size));
-
- /* N.B. ret_sz carried into this block ... */
- mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
- if (mx_sc_elems < 0)
- return mx_sc_elems; /* most likely -ENOMEM */
-
- num = scatter_elem_sz;
- if (unlikely(num != scatter_elem_sz_prev)) {
- if (num < PAGE_SIZE) {
- scatter_elem_sz = PAGE_SIZE;
- scatter_elem_sz_prev = PAGE_SIZE;
- } else
- scatter_elem_sz_prev = num;
- }
- for (k = 0, sg = schp->buffer, rem_sz = blk_size;
- (rem_sz > 0) && (k < mx_sc_elems);
- ++k, rem_sz -= ret_sz, ++sg) {
-
- num = (rem_sz > scatter_elem_sz_prev) ?
- scatter_elem_sz_prev : rem_sz;
- p = sg_page_malloc(num, sfp->low_dma, &ret_sz);
- if (!p)
- return -ENOMEM;
-
- if (num == scatter_elem_sz_prev) {
- if (unlikely(ret_sz > scatter_elem_sz_prev)) {
- scatter_elem_sz = ret_sz;
- scatter_elem_sz_prev = ret_sz;
- }
- }
- sg->page = p;
- sg->length = (ret_sz > num) ? num : ret_sz;
-
- SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k=%d, num=%d, "
- "ret_sz=%d\n", k, num, ret_sz));
- } /* end of for loop */
-
- schp->k_use_sg = k;
- SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k_use_sg=%d, "
- "rem_sz=%d\n", k, rem_sz));
-
- schp->bufflen = blk_size;
- if (rem_sz > 0) /* must have failed */
- return -ENOMEM;
-
- return 0;
-}
-
-static int
-sg_write_xfer(Sg_request * srp)
-{
- sg_io_hdr_t *hp = &srp->header;
- Sg_scatter_hold *schp = &srp->data;
- struct scatterlist *sg = schp->buffer;
- int num_xfer = 0;
- int j, k, onum, usglen, ksglen, res;
- int iovec_count = (int) hp->iovec_count;
- int dxfer_dir = hp->dxfer_direction;
- unsigned char *p;
- unsigned char __user *up;
- int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
-
- if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_TO_DEV == dxfer_dir) ||
- (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
- num_xfer = (int) (new_interface ? hp->dxfer_len : hp->flags);
- if (schp->bufflen < num_xfer)
- num_xfer = schp->bufflen;
+ if (!access_ok(VERIFY_READ, hp->dxferp,
+ SZ_SG_IOVEC * hp->iovec_count)) {
+ res = -EFAULT;
+ goto release_rbuf;
}
- if ((num_xfer <= 0) || (schp->dio_in_use) ||
- (new_interface
- && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
- return 0;
-
- SCSI_LOG_TIMEOUT(4, printk("sg_write_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
- num_xfer, iovec_count, schp->k_use_sg));
- if (iovec_count) {
- onum = iovec_count;
- if (!access_ok(VERIFY_READ, hp->dxferp, SZ_SG_IOVEC * onum))
- return -EFAULT;
- } else
- onum = 1;

- ksglen = sg->length;
- p = page_address(sg->page);
- for (j = 0, k = 0; j < onum; ++j) {
- res = sg_u_iovec(hp, iovec_count, j, 1, &usglen, &up);
- if (res)
- return res;
-
- for (; p; ++sg, ksglen = sg->length,
- p = page_address(sg->page)) {
- if (usglen <= 0)
- break;
- if (ksglen > usglen) {
- if (usglen >= num_xfer) {
- if (__copy_from_user(p, up, num_xfer))
- return -EFAULT;
- return 0;
- }
- if (__copy_from_user(p, up, usglen))
- return -EFAULT;
- p += usglen;
- ksglen -= usglen;
- break;
- } else {
- if (ksglen >= num_xfer) {
- if (__copy_from_user(p, up, num_xfer))
- return -EFAULT;
- return 0;
- }
- if (__copy_from_user(p, up, ksglen))
- return -EFAULT;
- up += ksglen;
- usglen -= ksglen;
- }
- ++k;
- if (k >= schp->k_use_sg)
- return 0;
- }
+ size = SZ_SG_IOVEC * hp->iovec_count;
+ u_iov = kmalloc(size, GFP_KERNEL);
+ if (!u_iov) {
+ res = -ENOMEM;
+ goto release_rbuf;
}

- return 0;
-}
+ if (copy_from_user(u_iov, hp->dxferp, size)) {
+ kfree(u_iov);
+ res = -EFAULT;
+ goto release_rbuf;
+ }

-static int
-sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind,
- int wr_xf, int *countp, unsigned char __user **up)
-{
- int num_xfer = (int) hp->dxfer_len;
- unsigned char __user *p = hp->dxferp;
- int count;
+ res = blk_rq_copy_user_iov(rq, u_iov, hp->iovec_count, dxfer_len,
+ rbuf);
+ kfree(u_iov);
+ if (res)
+ goto release_rbuf;

- if (0 == sg_num) {
- if (wr_xf && ('\0' == hp->interface_id))
- count = (int) hp->flags; /* holds "old" input_size */
- else
- count = num_xfer;
- } else {
- sg_iovec_t iovec;
- if (__copy_from_user(&iovec, p + ind*SZ_SG_IOVEC, SZ_SG_IOVEC))
- return -EFAULT;
- p = iovec.iov_base;
- count = (int) iovec.iov_len;
- }
- if (!access_ok(wr_xf ? VERIFY_READ : VERIFY_WRITE, p, count))
- return -EFAULT;
- if (up)
- *up = p;
- if (countp)
- *countp = count;
+done:
+ if (rbuf)
+ srp->res_used = 1;
return 0;
+
+release_rbuf:
+ if (rbuf)
+ bio_release_reserve_buf(rbuf);
+ return res;
}

static void
-sg_remove_scat(Sg_scatter_hold * schp)
+sg_finish_rem_req(Sg_request * srp)
{
- SCSI_LOG_TIMEOUT(4, printk("sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
- if (schp->buffer && (schp->sglist_len > 0)) {
- struct scatterlist *sg = schp->buffer;
+ Sg_fd *sfp = srp->parentfp;

- if (schp->dio_in_use) {
-#ifdef SG_ALLOW_DIO_CODE
- st_unmap_user_pages(sg, schp->k_use_sg, TRUE);
-#endif
- } else {
- int k;
-
- for (k = 0; (k < schp->k_use_sg) && sg->page;
- ++k, ++sg) {
- SCSI_LOG_TIMEOUT(5, printk(
- "sg_remove_scat: k=%d, pg=0x%p, len=%d\n",
- k, sg->page, sg->length));
- sg_page_free(sg->page, sg->length);
- }
- }
- kfree(schp->buffer);
+ SCSI_LOG_TIMEOUT(4, printk("sg_finish_rem_req: res_used=%d\n", (int) srp->res_used));
+
+ if (srp->bio) {
+ /*
+ * buffer is left from something like a signal or close
+ * which was being accessed at the time. We cannot copy
+ * back to userspace so just release buffers.
+ *
+ * BUG: the old sg.c and this code, can get run from a softirq
+ * and if dio was used then we need process context.
+ * TODO: either document that you cannot use DIO and the feature
+ * which closes devices or interrupts IO while DIO is in
+ * progress. Or do something like James process context exec
+ */
+ blk_rq_destroy_buffer(srp->bio);
+ sg_cleanup_transfer(srp);
}
- memset(schp, 0, sizeof (*schp));
+ sg_remove_request(sfp, srp);
}

static int
sg_read_xfer(Sg_request * srp)
{
sg_io_hdr_t *hp = &srp->header;
- Sg_scatter_hold *schp = &srp->data;
- struct scatterlist *sg = schp->buffer;
- int num_xfer = 0;
- int j, k, onum, usglen, ksglen, res;
int iovec_count = (int) hp->iovec_count;
- int dxfer_dir = hp->dxfer_direction;
- unsigned char *p;
- unsigned char __user *up;
int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
+ int res = 0, num_xfer = 0;
+ int dxfer_dir = hp->dxfer_direction;

- if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_FROM_DEV == dxfer_dir)
- || (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
- num_xfer = hp->dxfer_len;
- if (schp->bufflen < num_xfer)
- num_xfer = schp->bufflen;
- }
- if ((num_xfer <= 0) || (schp->dio_in_use) ||
- (new_interface
- && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
+ if (new_interface && (SG_FLAG_NO_DXFER & hp->flags))
return 0;

- SCSI_LOG_TIMEOUT(4, printk("sg_read_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
- num_xfer, iovec_count, schp->k_use_sg));
- if (iovec_count) {
- onum = iovec_count;
- if (!access_ok(VERIFY_READ, hp->dxferp, SZ_SG_IOVEC * onum))
- return -EFAULT;
- } else
- onum = 1;
-
- p = page_address(sg->page);
- ksglen = sg->length;
- for (j = 0, k = 0; j < onum; ++j) {
- res = sg_u_iovec(hp, iovec_count, j, 0, &usglen, &up);
- if (res)
- return res;
+ SCSI_LOG_TIMEOUT(4, printk("sg_read_xfer\n"));

- for (; p; ++sg, ksglen = sg->length,
- p = page_address(sg->page)) {
- if (usglen <= 0)
- break;
- if (ksglen > usglen) {
- if (usglen >= num_xfer) {
- if (__copy_to_user(up, p, num_xfer))
- return -EFAULT;
- return 0;
- }
- if (__copy_to_user(up, p, usglen))
- return -EFAULT;
- p += usglen;
- ksglen -= usglen;
- break;
- } else {
- if (ksglen >= num_xfer) {
- if (__copy_to_user(up, p, num_xfer))
- return -EFAULT;
- return 0;
- }
- if (__copy_to_user(up, p, ksglen))
- return -EFAULT;
- up += ksglen;
- usglen -= ksglen;
- }
- ++k;
- if (k >= schp->k_use_sg)
- return 0;
- }
- }
+ if (SG_DXFER_UNKNOWN == dxfer_dir ||
+ SG_DXFER_FROM_DEV == dxfer_dir ||
+ SG_DXFER_TO_FROM_DEV == dxfer_dir)
+ num_xfer = hp->dxfer_len;

- return 0;
-}
+ if (new_interface && (SG_FLAG_MMAP_IO & hp->flags))
+ blk_rq_destroy_buffer(srp->bio);
+ else if (iovec_count) {
+ int size;
+ struct sg_iovec *u_iov;

-static int
-sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
-{
- Sg_scatter_hold *schp = &srp->data;
- struct scatterlist *sg = schp->buffer;
- int k, num;
+ if (!access_ok(VERIFY_READ, hp->dxferp,
+ SZ_SG_IOVEC * iovec_count))
+ return -EFAULT;

- SCSI_LOG_TIMEOUT(4, printk("sg_read_oxfer: num_read_xfer=%d\n",
- num_read_xfer));
- if ((!outp) || (num_read_xfer <= 0))
- return 0;
+ size = SZ_SG_IOVEC * iovec_count;
+ u_iov = kmalloc(size, GFP_KERNEL);
+ if (!u_iov)
+ return -ENOMEM;

- for (k = 0; (k < schp->k_use_sg) && sg->page; ++k, ++sg) {
- num = sg->length;
- if (num > num_read_xfer) {
- if (__copy_to_user(outp, page_address(sg->page),
- num_read_xfer))
- return -EFAULT;
- break;
- } else {
- if (__copy_to_user(outp, page_address(sg->page),
- num))
- return -EFAULT;
- num_read_xfer -= num;
- if (num_read_xfer <= 0)
- break;
- outp += num;
+ if (copy_from_user(u_iov, hp->dxferp, size)) {
+ kfree(u_iov);
+ return -EFAULT;
}
- }

- return 0;
+ res = blk_rq_uncopy_user_iov(srp->bio, u_iov, iovec_count);
+ kfree(u_iov);
+ } else {
+ /* map user or non iovec copy user */
+ res = blk_rq_complete_transfer(srp->bio, hp->dxferp, num_xfer);
+ }
+ sg_cleanup_transfer(srp);
+ return res;
}

-static void
+static int
sg_build_reserve(Sg_fd * sfp, int req_size)
{
- Sg_scatter_hold *schp = &sfp->reserve;
+ struct request_queue *q = sfp->parentdp->device->request_queue;
+ int res;

SCSI_LOG_TIMEOUT(4, printk("sg_build_reserve: req_size=%d\n", req_size));
- do {
- if (req_size < PAGE_SIZE)
- req_size = PAGE_SIZE;
- if (0 == sg_build_indirect(schp, sfp, req_size))
- return;
- else
- sg_remove_scat(schp);
- req_size >>= 1; /* divide by 2 */
- } while (req_size > (PAGE_SIZE / 2));
-}
+ if (req_size < 0)
+ return -EINVAL;

-static void
-sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
-{
- Sg_scatter_hold *req_schp = &srp->data;
- Sg_scatter_hold *rsv_schp = &sfp->reserve;
- struct scatterlist *sg = rsv_schp->buffer;
- int k, num, rem;
-
- srp->res_used = 1;
- SCSI_LOG_TIMEOUT(4, printk("sg_link_reserve: size=%d\n", size));
- rem = size;
-
- for (k = 0; k < rsv_schp->k_use_sg; ++k, ++sg) {
- num = sg->length;
- if (rem <= num) {
- sfp->save_scat_len = num;
- sg->length = rem;
- req_schp->k_use_sg = k + 1;
- req_schp->sglist_len = rsv_schp->sglist_len;
- req_schp->buffer = rsv_schp->buffer;
-
- req_schp->bufflen = size;
- req_schp->b_malloc_len = rsv_schp->b_malloc_len;
- break;
- } else
- rem -= num;
- }
+ if (sfp->reserve.rbuf && (sfp->reserve.rbuf->buf_size == req_size))
+ return 0;

- if (k >= rsv_schp->k_use_sg)
- SCSI_LOG_TIMEOUT(1, printk("sg_link_reserve: BAD size\n"));
-}
+ if (sfp->mmap_called)
+ return -EBUSY;

-static void
-sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
-{
- Sg_scatter_hold *req_schp = &srp->data;
- Sg_scatter_hold *rsv_schp = &sfp->reserve;
+ if (sfp->reserve.rbuf) {
+ res = bio_free_reserve_buf(sfp->reserve.rbuf);
+ if (res)
+ /* it is in use */
+ return res;
+ sfp->reserve.rbuf = NULL;
+ }

- SCSI_LOG_TIMEOUT(4, printk("sg_unlink_reserve: req->k_use_sg=%d\n",
- (int) req_schp->k_use_sg));
- if ((rsv_schp->k_use_sg > 0) && (req_schp->k_use_sg > 0)) {
- struct scatterlist *sg = rsv_schp->buffer;
+ sfp->reserve.bufflen = 0;
+ sfp->reserve.k_use_sg = 0;

- if (sfp->save_scat_len > 0)
- (sg + (req_schp->k_use_sg - 1))->length =
- (unsigned) sfp->save_scat_len;
- else
- SCSI_LOG_TIMEOUT(1, printk ("sg_unlink_reserve: BAD save_scat_len\n"));
- }
- req_schp->k_use_sg = 0;
- req_schp->bufflen = 0;
- req_schp->buffer = NULL;
- req_schp->sglist_len = 0;
- sfp->save_scat_len = 0;
- srp->res_used = 0;
+ sfp->reserve.rbuf = bio_alloc_reserve_buf(q, req_size);
+ if (!sfp->reserve.rbuf)
+ return res;
+ sfp->reserve.bufflen = sfp->reserve.rbuf->buf_size;
+ sfp->reserve.k_use_sg = sfp->reserve.rbuf->sg_count;
+ return 0;
}

static Sg_request *
@@ -2370,6 +1915,7 @@ sg_add_sfp(Sg_device * sdp, int dev)
sg_big_buff = def_reserved_size;

sg_build_reserve(sfp, sg_big_buff);
+
SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: bufflen=%d, k_use_sg=%d\n",
sfp->reserve.bufflen, sfp->reserve.k_use_sg));
return sfp;
@@ -2397,7 +1943,8 @@ __sg_remove_sfp(Sg_device * sdp, Sg_fd *
SCSI_LOG_TIMEOUT(6,
printk("__sg_remove_sfp: bufflen=%d, k_use_sg=%d\n",
(int) sfp->reserve.bufflen, (int) sfp->reserve.k_use_sg));
- sg_remove_scat(&sfp->reserve);
+ bio_free_reserve_buf(sfp->reserve.rbuf);
+ sfp->reserve.bufflen = 0;
}
sfp->parentdp = NULL;
SCSI_LOG_TIMEOUT(6, printk("__sg_remove_sfp: sfp=0x%p\n", sfp));
@@ -2451,67 +1998,6 @@ sg_remove_sfp(Sg_device * sdp, Sg_fd * s
return res;
}

-static int
-sg_res_in_use(Sg_fd * sfp)
-{
- const Sg_request *srp;
- unsigned long iflags;
-
- read_lock_irqsave(&sfp->rq_list_lock, iflags);
- for (srp = sfp->headrp; srp; srp = srp->nextrp)
- if (srp->res_used)
- break;
- read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
- return srp ? 1 : 0;
-}
-
-/* The size fetched (value output via retSzp) set when non-NULL return */
-static struct page *
-sg_page_malloc(int rqSz, int lowDma, int *retSzp)
-{
- struct page *resp = NULL;
- gfp_t page_mask;
- int order, a_size;
- int resSz;
-
- if ((rqSz <= 0) || (NULL == retSzp))
- return resp;
-
- if (lowDma)
- page_mask = GFP_ATOMIC | GFP_DMA | __GFP_COMP | __GFP_NOWARN;
- else
- page_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN;
-
- for (order = 0, a_size = PAGE_SIZE; a_size < rqSz;
- order++, a_size <<= 1) ;
- resSz = a_size; /* rounded up if necessary */
- resp = alloc_pages(page_mask, order);
- while ((!resp) && order) {
- --order;
- a_size >>= 1; /* divide by 2, until PAGE_SIZE */
- resp = alloc_pages(page_mask, order); /* try half */
- resSz = a_size;
- }
- if (resp) {
- if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
- memset(page_address(resp), 0, resSz);
- *retSzp = resSz;
- }
- return resp;
-}
-
-static void
-sg_page_free(struct page *page, int size)
-{
- int order, a_size;
-
- if (!page)
- return;
- for (order = 0, a_size = PAGE_SIZE; a_size < size;
- order++, a_size <<= 1) ;
- __free_pages(page, order);
-}
-
#ifndef MAINTENANCE_IN_CMD
#define MAINTENANCE_IN_CMD 0xa3
#endif
--
1.4.1.1