RDMA/usnic: Do not use ucontext->tgid

Update this driver to match the code it copies from umem.c which no longer
uses tgid.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

diff --git a/drivers/infiniband/hw/usnic/usnic_uiom.c b/drivers/infiniband/hw/usnic/usnic_uiom.c
index 9dd39da..49275a5 100644 (file)
--- a/drivers/infiniband/hw/usnic/usnic_uiom.c
+++ b/drivers/infiniband/hw/usnic/usnic_uiom.c
@@ -54,18 +54,6 @@ static struct workqueue_struct *usnic_uiom_wq;
        ((void *) &((struct usnic_uiom_chunk *) 0)->page_list[1] -      \
        (void *) &((struct usnic_uiom_chunk *) 0)->page_list[0]))
 
-static void usnic_uiom_reg_account(struct work_struct *work)
-{
-       struct usnic_uiom_reg *umem = container_of(work,
-                                               struct usnic_uiom_reg, work);
-
-       down_write(&umem->mm->mmap_sem);
-       umem->mm->locked_vm -= umem->diff;
-       up_write(&umem->mm->mmap_sem);
-       mmput(umem->mm);
-       kfree(umem);
-}
-
 static int usnic_uiom_dma_fault(struct iommu_domain *domain,
                                struct device *dev,
                                unsigned long iova, int flags,
@@ -99,8 +87,9 @@ static void usnic_uiom_put_pages(struct list_head *chunk_list, int dirty)
 }
 
 static int usnic_uiom_get_pages(unsigned long addr, size_t size, int writable,
-                               int dmasync, struct list_head *chunk_list)
+                               int dmasync, struct usnic_uiom_reg *uiomr)
 {
+       struct list_head *chunk_list = &uiomr->chunk_list;
        struct page **page_list;
        struct scatterlist *sg;
        struct usnic_uiom_chunk *chunk;
@@ -114,6 +103,7 @@ static int usnic_uiom_get_pages(unsigned long addr, size_t size, int writable,
        int flags;
        dma_addr_t pa;
        unsigned int gup_flags;
+       struct mm_struct *mm;
 
        /*
         * If the combination of the addr and size requested for this memory
@@ -136,7 +126,8 @@ static int usnic_uiom_get_pages(unsigned long addr, size_t size, int writable,
 
        npages = PAGE_ALIGN(size + (addr & ~PAGE_MASK)) >> PAGE_SHIFT;
 
-       down_write(&current->mm->mmap_sem);
+       uiomr->owning_mm = mm = current->mm;
+       down_write(&mm->mmap_sem);
 
        locked = npages + current->mm->pinned_vm;
        lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
@@ -196,10 +187,12 @@ static int usnic_uiom_get_pages(unsigned long addr, size_t size, int writable,
 out:
        if (ret < 0)
                usnic_uiom_put_pages(chunk_list, 0);
-       else
-               current->mm->pinned_vm = locked;
+       else {
+               mm->pinned_vm = locked;
+               mmgrab(uiomr->owning_mm);
+       }
 
-       up_write(&current->mm->mmap_sem);
+       up_write(&mm->mmap_sem);
        free_page((unsigned long) page_list);
        return ret;
 }
@@ -379,7 +372,7 @@ struct usnic_uiom_reg *usnic_uiom_reg_get(struct usnic_uiom_pd *pd,
        uiomr->pd = pd;
 
        err = usnic_uiom_get_pages(addr, size, writable, dmasync,
-                                       &uiomr->chunk_list);
+                                  uiomr);
        if (err) {
                usnic_err("Failed get_pages vpn [0x%lx,0x%lx] err %d\n",
                                vpn_start, vpn_last, err);
@@ -426,29 +419,39 @@ out_put_intervals:
 out_put_pages:
        usnic_uiom_put_pages(&uiomr->chunk_list, 0);
        spin_unlock(&pd->lock);
+       mmdrop(uiomr->owning_mm);
 out_free_uiomr:
        kfree(uiomr);
        return ERR_PTR(err);
 }
 
-void usnic_uiom_reg_release(struct usnic_uiom_reg *uiomr,
-                           struct ib_ucontext *ucontext)
+static void __usnic_uiom_release_tail(struct usnic_uiom_reg *uiomr)
 {
-       struct task_struct *task;
-       struct mm_struct *mm;
-       unsigned long diff;
+       mmdrop(uiomr->owning_mm);
+       kfree(uiomr);
+}
 
-       __usnic_uiom_reg_release(uiomr->pd, uiomr, 1);
+static inline size_t usnic_uiom_num_pages(struct usnic_uiom_reg *uiomr)
+{
+       return PAGE_ALIGN(uiomr->length + uiomr->offset) >> PAGE_SHIFT;
+}
 
-       task = get_pid_task(ucontext->tgid, PIDTYPE_PID);
-       if (!task)
-               goto out;
-       mm = get_task_mm(task);
-       put_task_struct(task);
-       if (!mm)
-               goto out;
+static void usnic_uiom_release_defer(struct work_struct *work)
+{
+       struct usnic_uiom_reg *uiomr =
+               container_of(work, struct usnic_uiom_reg, work);
 
-       diff = PAGE_ALIGN(uiomr->length + uiomr->offset) >> PAGE_SHIFT;
+       down_write(&uiomr->owning_mm->mmap_sem);
+       uiomr->owning_mm->pinned_vm -= usnic_uiom_num_pages(uiomr);
+       up_write(&uiomr->owning_mm->mmap_sem);
+
+       __usnic_uiom_release_tail(uiomr);
+}
+
+void usnic_uiom_reg_release(struct usnic_uiom_reg *uiomr,
+                           struct ib_ucontext *context)
+{
+       __usnic_uiom_reg_release(uiomr->pd, uiomr, 1);
 
        /*
         * We may be called with the mm's mmap_sem already held.  This
@@ -456,25 +459,21 @@ void usnic_uiom_reg_release(struct usnic_uiom_reg *uiomr,
         * the last reference to our file and calls our release
         * method.  If there are memory regions to destroy, we'll end
         * up here and not be able to take the mmap_sem.  In that case
-        * we defer the vm_locked accounting to the system workqueue.
+        * we defer the vm_locked accounting to a workqueue.
         */
-       if (ucontext->closing) {
-               if (!down_write_trylock(&mm->mmap_sem)) {
-                       INIT_WORK(&uiomr->work, usnic_uiom_reg_account);
-                       uiomr->mm = mm;
-                       uiomr->diff = diff;
-
+       if (context->closing) {
+               if (!down_write_trylock(&uiomr->owning_mm->mmap_sem)) {
+                       INIT_WORK(&uiomr->work, usnic_uiom_release_defer);
                        queue_work(usnic_uiom_wq, &uiomr->work);
                        return;
                }
-       } else
-               down_write(&mm->mmap_sem);
+       } else {
+               down_write(&uiomr->owning_mm->mmap_sem);
+       }
+       uiomr->owning_mm->pinned_vm -= usnic_uiom_num_pages(uiomr);
+       up_write(&uiomr->owning_mm->mmap_sem);
 
-       mm->pinned_vm -= diff;
-       up_write(&mm->mmap_sem);
-       mmput(mm);
-out:
-       kfree(uiomr);
+       __usnic_uiom_release_tail(uiomr);
 }
 
 struct usnic_uiom_pd *usnic_uiom_alloc_pd(void)

diff --git a/drivers/infiniband/hw/usnic/usnic_uiom.h b/drivers/infiniband/hw/usnic/usnic_uiom.h
index 8c096ac..b86a973 100644 (file)
--- a/drivers/infiniband/hw/usnic/usnic_uiom.h
+++ b/drivers/infiniband/hw/usnic/usnic_uiom.h
@@ -71,8 +71,7 @@ struct usnic_uiom_reg {
        int                             writable;
        struct list_head                chunk_list;
        struct work_struct              work;
-       struct mm_struct                *mm;
-       unsigned long                   diff;
+       struct mm_struct                *owning_mm;
 };
 
 struct usnic_uiom_chunk {