From f7c6a7b5d59980b076abbf2ceeb8735591290285 Mon Sep 17 00:00:00 2001 From: Roland Dreier Date: Sun, 4 Mar 2007 16:15:11 -0800 Subject: IB/uverbs: Export ib_umem_get()/ib_umem_release() to modules Export ib_umem_get()/ib_umem_release() and put low-level drivers in control of when to call ib_umem_get() to pin and DMA map userspace, rather than always calling it in ib_uverbs_reg_mr() before calling the low-level driver's reg_user_mr method. Also move these functions to be in the ib_core module instead of ib_uverbs, so that driver modules using them do not depend on ib_uverbs. This has a number of advantages: - It is better design from the standpoint of making generic code a library that can be used or overridden by device-specific code as the details of specific devices dictate. - Drivers that do not need to pin userspace memory regions do not need to take the performance hit of calling ib_mem_get(). For example, although I have not tried to implement it in this patch, the ipath driver should be able to avoid pinning memory and just use copy_{to,from}_user() to access userspace memory regions. - Buffers that need special mapping treatment can be identified by the low-level driver. For example, it may be possible to solve some Altix-specific memory ordering issues with mthca CQs in userspace by mapping CQ buffers with extra flags. - Drivers that need to pin and DMA map userspace memory for things other than memory regions can use ib_umem_get() directly, instead of hacks using extra parameters to their reg_phys_mr method. For example, the mlx4 driver that is pending being merged needs to pin and DMA map QP and CQ buffers, but it does not need to create a memory key for these buffers. So the cleanest solution is for mlx4 to call ib_umem_get() in the create_qp and create_cq methods. Signed-off-by: Roland Dreier --- drivers/infiniband/hw/cxgb3/iwch_provider.c | 28 ++++++++++++++++++++-------- 1 file changed, 20 insertions(+), 8 deletions(-) (limited to 'drivers/infiniband/hw/cxgb3/iwch_provider.c') diff --git a/drivers/infiniband/hw/cxgb3/iwch_provider.c b/drivers/infiniband/hw/cxgb3/iwch_provider.c index a891493fd34..e7c2c394803 100644 --- a/drivers/infiniband/hw/cxgb3/iwch_provider.c +++ b/drivers/infiniband/hw/cxgb3/iwch_provider.c @@ -47,6 +47,7 @@ #include #include #include +#include #include #include "cxio_hal.h" @@ -443,6 +444,8 @@ static int iwch_dereg_mr(struct ib_mr *ib_mr) remove_handle(rhp, &rhp->mmidr, mmid); if (mhp->kva) kfree((void *) (unsigned long) mhp->kva); + if (mhp->umem) + ib_umem_release(mhp->umem); PDBG("%s mmid 0x%x ptr %p\n", __FUNCTION__, mmid, mhp); kfree(mhp); return 0; @@ -577,8 +580,8 @@ static int iwch_reregister_phys_mem(struct ib_mr *mr, } -static struct ib_mr *iwch_reg_user_mr(struct ib_pd *pd, struct ib_umem *region, - int acc, struct ib_udata *udata) +static struct ib_mr *iwch_reg_user_mr(struct ib_pd *pd, u64 start, u64 length, + u64 virt, int acc, struct ib_udata *udata) { __be64 *pages; int shift, n, len; @@ -591,7 +594,6 @@ static struct ib_mr *iwch_reg_user_mr(struct ib_pd *pd, struct ib_umem *region, struct iwch_reg_user_mr_resp uresp; PDBG("%s ib_pd %p\n", __FUNCTION__, pd); - shift = ffs(region->page_size) - 1; php = to_iwch_pd(pd); rhp = php->rhp; @@ -599,8 +601,17 @@ static struct ib_mr *iwch_reg_user_mr(struct ib_pd *pd, struct ib_umem *region, if (!mhp) return ERR_PTR(-ENOMEM); + mhp->umem = ib_umem_get(pd->uobject->context, start, length, acc); + if (IS_ERR(mhp->umem)) { + err = PTR_ERR(mhp->umem); + kfree(mhp); + return ERR_PTR(err); + } + + shift = ffs(mhp->umem->page_size) - 1; + n = 0; - list_for_each_entry(chunk, ®ion->chunk_list, list) + list_for_each_entry(chunk, &mhp->umem->chunk_list, list) n += chunk->nents; pages = kmalloc(n * sizeof(u64), GFP_KERNEL); @@ -611,13 +622,13 @@ static struct ib_mr *iwch_reg_user_mr(struct ib_pd *pd, struct ib_umem *region, i = n = 0; - list_for_each_entry(chunk, ®ion->chunk_list, list) + list_for_each_entry(chunk, &mhp->umem->chunk_list, list) for (j = 0; j < chunk->nmap; ++j) { len = sg_dma_len(&chunk->page_list[j]) >> shift; for (k = 0; k < len; ++k) { pages[i++] = cpu_to_be64(sg_dma_address( &chunk->page_list[j]) + - region->page_size * k); + mhp->umem->page_size * k); } } @@ -625,9 +636,9 @@ static struct ib_mr *iwch_reg_user_mr(struct ib_pd *pd, struct ib_umem *region, mhp->attr.pdid = php->pdid; mhp->attr.zbva = 0; mhp->attr.perms = iwch_ib_to_tpt_access(acc); - mhp->attr.va_fbo = region->virt_base; + mhp->attr.va_fbo = virt; mhp->attr.page_size = shift - 12; - mhp->attr.len = (u32) region->length; + mhp->attr.len = (u32) length; mhp->attr.pbl_size = i; err = iwch_register_mem(rhp, php, mhp, shift, pages); kfree(pages); @@ -650,6 +661,7 @@ static struct ib_mr *iwch_reg_user_mr(struct ib_pd *pd, struct ib_umem *region, return &mhp->ibmr; err: + ib_umem_release(mhp->umem); kfree(mhp); return ERR_PTR(err); } -- cgit v1.2.3