This patch makes sg dio use the block layer functions (blk_rq_map_user, blk_execute_rq_nowait, etc). It's an updated version of the following patch: http://marc.theaimsgroup.com/?l=linux-scsi&m=116527334121826&w=2 This doesn't break any existing features. While it converts sg dio to use the block layer functions, sg mmap and indirect io still use scsi_execute_async. This is against the Linus' tree (uses the latest block layer API) since the scsi-misc is a bit out-of-data. On a side note, Mike has been working on converting sg mmap and indirectio to the block layer functions. Signed-off-by: FUJITA Tomonori <fujita.tomonori@xxxxxxxxxxxxx> --- drivers/scsi/sg.c | 201 ++++++++++++++++------------------------------------- 1 files changed, 59 insertions(+), 142 deletions(-) diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c index 81e3bc7..304e34b 100644 --- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -136,6 +136,8 @@ typedef struct sg_request { /* SG_MAX_QU char orphan; /* 1 -> drop on sight, 0 -> normal */ char sg_io_owned; /* 1 -> packet belongs to SG_IO */ volatile char done; /* 0->before bh, 1->before read, 2->read */ + struct request *rq; + struct bio *bio; } Sg_request; typedef struct sg_fd { /* holds the state of a file descriptor */ @@ -690,6 +692,11 @@ sg_new_write(Sg_fd * sfp, const char __u return count; } +static void sg_rq_end_io(struct request *rq, int uptodate) +{ + sg_cmd_done(rq->end_io_data, rq->sense, rq->errors, rq->data_len); +} + static int sg_common_write(Sg_fd * sfp, Sg_request * srp, unsigned char *cmnd, int timeout, int blocking) @@ -742,6 +749,14 @@ sg_common_write(Sg_fd * sfp, Sg_request 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 (hp->info & SG_INFO_DIRECT_IO) { + memcpy(srp->rq->cmd, cmnd, hp->cmd_len); + srp->rq->timeout = timeout; + blk_execute_rq_nowait(sdp->device->request_queue, sdp->disk, + srp->rq, 1, sg_rq_end_io); + return 0; + } + 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, @@ -1651,7 +1666,10 @@ sg_finish_rem_req(Sg_request * srp) 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 + else if (req_schp->dio_in_use) { + blk_rq_unmap_user(srp->bio); + blk_put_request(srp->rq); + } else sg_remove_scat(req_schp); sg_remove_request(sfp, srp); } @@ -1677,122 +1695,20 @@ sg_build_sgat(Sg_scatter_hold * schp, co 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; - - /* Too big */ - if (nr_pages > max_pages) - return -ENOMEM; - - /* Hmm? */ - if (count == 0) - 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(¤t->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(¤t->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; */ - } - - 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; - } - - kfree(pages); - return nr_pages; - - out_unmap: - if (res > 0) { - for (j=0; j < res; j++) - page_cache_release(pages[j]); - res = 0; - } - kfree(pages); - return res; -} - - -/* And unmap them... */ -static int -st_unmap_user_pages(struct scatterlist *sgl, const unsigned int nr_pages, - int dirtied) +/* taken from the bsg tree */ +static int blk_fill_sghdr_rq(request_queue_t *q, struct request *rq, + struct sg_io_hdr *hdr, int has_write_perm) { - 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); - } + memset(rq->cmd, 0, BLK_MAX_CDB); /* ATAPI hates garbage after CDB */ + /* + * fill in request structure + */ + rq->cmd_len = hdr->cmd_len; + rq->cmd_type = REQ_TYPE_BLOCK_PC; return 0; } -/* ^^^^^^^^ above code borrowed from st driver's direct IO ^^^^^^^^^ */ -#endif - - /* Returns: -ve -> error, 0 -> done, 1 -> try indirect */ static int sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len) @@ -1800,26 +1716,34 @@ sg_build_direct(Sg_request * srp, Sg_fd #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; + int res, rw; + request_queue_t *q = sfp->parentdp->device->request_queue; + struct request *rq; - if (((unsigned long)hp->dxferp & - queue_dma_alignment(sdev->request_queue)) != 0) + if (((unsigned long)hp->dxferp & queue_dma_alignment(q))) return 1; - 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; + rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ; + + rq = blk_get_request(q, rw, GFP_ATOMIC); + if (!rq) + return -ENOMEM; + + res = blk_fill_sghdr_rq(q, rq, hp, rw); + if (res) { + blk_put_request(rq); + return res; + } + + res = blk_rq_map_user(q, rq, hp->dxferp, dxfer_len); + if (res) { + blk_put_request(rq); + return res; } - schp->k_use_sg = res; + + srp->rq = rq; + srp->bio = rq->bio; + rq->end_io_data = srp; schp->dio_in_use = 1; hp->info |= SG_INFO_DIRECT_IO; return 0; @@ -2002,23 +1926,16 @@ static void sg_remove_scat(Sg_scatter_hold * schp) { 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; + int k; - 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); - } + 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); } -- 1.4.3.2 - To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
