]> git.proxmox.com Git - mirror_ubuntu-hirsute-kernel.git/commitdiff
rdma/siw: application buffer management
authorBernard Metzler <bmt@zurich.ibm.com>
Thu, 20 Jun 2019 16:21:28 +0000 (18:21 +0200)
committerJason Gunthorpe <jgg@mellanox.com>
Tue, 2 Jul 2019 20:03:40 +0000 (17:03 -0300)
Broken up commit to add the Soft iWarp RDMA driver.

Signed-off-by: Bernard Metzler <bmt@zurich.ibm.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
drivers/infiniband/sw/siw/siw_mem.c [new file with mode: 0644]
drivers/infiniband/sw/siw/siw_mem.h [new file with mode: 0644]

diff --git a/drivers/infiniband/sw/siw/siw_mem.c b/drivers/infiniband/sw/siw/siw_mem.c
new file mode 100644 (file)
index 0000000..67171c8
--- /dev/null
@@ -0,0 +1,460 @@
+// SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause
+
+/* Authors: Bernard Metzler <bmt@zurich.ibm.com> */
+/* Copyright (c) 2008-2019, IBM Corporation */
+
+#include <linux/gfp.h>
+#include <rdma/ib_verbs.h>
+#include <linux/dma-mapping.h>
+#include <linux/slab.h>
+#include <linux/sched/mm.h>
+#include <linux/resource.h>
+
+#include "siw.h"
+#include "siw_mem.h"
+
+/*
+ * Stag lookup is based on its index part only (24 bits).
+ * The code avoids special Stag of zero and tries to randomize
+ * STag values between 1 and SIW_STAG_MAX_INDEX.
+ */
+int siw_mem_add(struct siw_device *sdev, struct siw_mem *m)
+{
+       struct xa_limit limit = XA_LIMIT(1, 0x00ffffff);
+       u32 id, next;
+
+       get_random_bytes(&next, 4);
+       next &= 0x00ffffff;
+
+       if (xa_alloc_cyclic(&sdev->mem_xa, &id, m, limit, &next,
+           GFP_KERNEL) < 0)
+               return -ENOMEM;
+
+       /* Set the STag index part */
+       m->stag = id << 8;
+
+       siw_dbg_mem(m, "new MEM object\n");
+
+       return 0;
+}
+
+/*
+ * siw_mem_id2obj()
+ *
+ * resolves memory from stag given by id. might be called from:
+ * o process context before sending out of sgl, or
+ * o in softirq when resolving target memory
+ */
+struct siw_mem *siw_mem_id2obj(struct siw_device *sdev, int stag_index)
+{
+       struct siw_mem *mem;
+
+       rcu_read_lock();
+       mem = xa_load(&sdev->mem_xa, stag_index);
+       if (likely(mem && kref_get_unless_zero(&mem->ref))) {
+               rcu_read_unlock();
+               return mem;
+       }
+       rcu_read_unlock();
+
+       return NULL;
+}
+
+static void siw_free_plist(struct siw_page_chunk *chunk, int num_pages,
+                          bool dirty)
+{
+       struct page **p = chunk->plist;
+
+       while (num_pages--) {
+               if (!PageDirty(*p) && dirty)
+                       put_user_pages_dirty_lock(p, 1);
+               else
+                       put_user_page(*p);
+               p++;
+       }
+}
+
+void siw_umem_release(struct siw_umem *umem, bool dirty)
+{
+       struct mm_struct *mm_s = umem->owning_mm;
+       int i, num_pages = umem->num_pages;
+
+       for (i = 0; num_pages; i++) {
+               int to_free = min_t(int, PAGES_PER_CHUNK, num_pages);
+
+               siw_free_plist(&umem->page_chunk[i], to_free,
+                              umem->writable && dirty);
+               kfree(umem->page_chunk[i].plist);
+               num_pages -= to_free;
+       }
+       atomic64_sub(umem->num_pages, &mm_s->pinned_vm);
+
+       mmdrop(mm_s);
+       kfree(umem->page_chunk);
+       kfree(umem);
+}
+
+int siw_mr_add_mem(struct siw_mr *mr, struct ib_pd *pd, void *mem_obj,
+                  u64 start, u64 len, int rights)
+{
+       struct siw_device *sdev = to_siw_dev(pd->device);
+       struct siw_mem *mem = kzalloc(sizeof(*mem), GFP_KERNEL);
+       struct xa_limit limit = XA_LIMIT(1, 0x00ffffff);
+       u32 id, next;
+
+       if (!mem)
+               return -ENOMEM;
+
+       mem->mem_obj = mem_obj;
+       mem->stag_valid = 0;
+       mem->sdev = sdev;
+       mem->va = start;
+       mem->len = len;
+       mem->pd = pd;
+       mem->perms = rights & IWARP_ACCESS_MASK;
+       kref_init(&mem->ref);
+
+       mr->mem = mem;
+
+       get_random_bytes(&next, 4);
+       next &= 0x00ffffff;
+
+       if (xa_alloc_cyclic(&sdev->mem_xa, &id, mem, limit, &next,
+           GFP_KERNEL) < 0) {
+               kfree(mem);
+               return -ENOMEM;
+       }
+       /* Set the STag index part */
+       mem->stag = id << 8;
+       mr->base_mr.lkey = mr->base_mr.rkey = mem->stag;
+
+       return 0;
+}
+
+void siw_mr_drop_mem(struct siw_mr *mr)
+{
+       struct siw_mem *mem = mr->mem, *found;
+
+       mem->stag_valid = 0;
+
+       /* make STag invalid visible asap */
+       smp_mb();
+
+       found = xa_erase(&mem->sdev->mem_xa, mem->stag >> 8);
+       WARN_ON(found != mem);
+       siw_mem_put(mem);
+}
+
+void siw_free_mem(struct kref *ref)
+{
+       struct siw_mem *mem = container_of(ref, struct siw_mem, ref);
+
+       siw_dbg_mem(mem, "free mem, pbl: %s\n", mem->is_pbl ? "y" : "n");
+
+       if (!mem->is_mw && mem->mem_obj) {
+               if (mem->is_pbl == 0)
+                       siw_umem_release(mem->umem, true);
+               else
+                       kfree(mem->pbl);
+       }
+       kfree(mem);
+}
+
+/*
+ * siw_check_mem()
+ *
+ * Check protection domain, STAG state, access permissions and
+ * address range for memory object.
+ *
+ * @pd:                Protection Domain memory should belong to
+ * @mem:       memory to be checked
+ * @addr:      starting addr of mem
+ * @perms:     requested access permissions
+ * @len:       len of memory interval to be checked
+ *
+ */
+int siw_check_mem(struct ib_pd *pd, struct siw_mem *mem, u64 addr,
+                 enum ib_access_flags perms, int len)
+{
+       if (!mem->stag_valid) {
+               siw_dbg_pd(pd, "STag 0x%08x invalid\n", mem->stag);
+               return -E_STAG_INVALID;
+       }
+       if (mem->pd != pd) {
+               siw_dbg_pd(pd, "STag 0x%08x: PD mismatch\n", mem->stag);
+               return -E_PD_MISMATCH;
+       }
+       /*
+        * check access permissions
+        */
+       if ((mem->perms & perms) < perms) {
+               siw_dbg_pd(pd, "permissions 0x%08x < 0x%08x\n",
+                          mem->perms, perms);
+               return -E_ACCESS_PERM;
+       }
+       /*
+        * Check if access falls into valid memory interval.
+        */
+       if (addr < mem->va || addr + len > mem->va + mem->len) {
+               siw_dbg_pd(pd, "MEM interval len %d\n", len);
+               siw_dbg_pd(pd, "[0x%016llx, 0x%016llx] out of bounds\n",
+                          (unsigned long long)addr,
+                          (unsigned long long)(addr + len));
+               siw_dbg_pd(pd, "[0x%016llx, 0x%016llx] STag=0x%08x\n",
+                          (unsigned long long)mem->va,
+                          (unsigned long long)(mem->va + mem->len),
+                          mem->stag);
+
+               return -E_BASE_BOUNDS;
+       }
+       return E_ACCESS_OK;
+}
+
+/*
+ * siw_check_sge()
+ *
+ * Check SGE for access rights in given interval
+ *
+ * @pd:                Protection Domain memory should belong to
+ * @sge:       SGE to be checked
+ * @mem:       location of memory reference within array
+ * @perms:     requested access permissions
+ * @off:       starting offset in SGE
+ * @len:       len of memory interval to be checked
+ *
+ * NOTE: Function references SGE's memory object (mem->obj)
+ * if not yet done. New reference is kept if check went ok and
+ * released if check failed. If mem->obj is already valid, no new
+ * lookup is being done and mem is not released it check fails.
+ */
+int siw_check_sge(struct ib_pd *pd, struct siw_sge *sge, struct siw_mem *mem[],
+                 enum ib_access_flags perms, u32 off, int len)
+{
+       struct siw_device *sdev = to_siw_dev(pd->device);
+       struct siw_mem *new = NULL;
+       int rv = E_ACCESS_OK;
+
+       if (len + off > sge->length) {
+               rv = -E_BASE_BOUNDS;
+               goto fail;
+       }
+       if (*mem == NULL) {
+               new = siw_mem_id2obj(sdev, sge->lkey >> 8);
+               if (unlikely(!new)) {
+                       siw_dbg_pd(pd, "STag unknown: 0x%08x\n", sge->lkey);
+                       rv = -E_STAG_INVALID;
+                       goto fail;
+               }
+               *mem = new;
+       }
+       /* Check if user re-registered with different STag key */
+       if (unlikely((*mem)->stag != sge->lkey)) {
+               siw_dbg_mem((*mem), "STag mismatch: 0x%08x\n", sge->lkey);
+               rv = -E_STAG_INVALID;
+               goto fail;
+       }
+       rv = siw_check_mem(pd, *mem, sge->laddr + off, perms, len);
+       if (unlikely(rv))
+               goto fail;
+
+       return 0;
+
+fail:
+       if (new) {
+               *mem = NULL;
+               siw_mem_put(new);
+       }
+       return rv;
+}
+
+void siw_wqe_put_mem(struct siw_wqe *wqe, enum siw_opcode op)
+{
+       switch (op) {
+       case SIW_OP_SEND:
+       case SIW_OP_WRITE:
+       case SIW_OP_SEND_WITH_IMM:
+       case SIW_OP_SEND_REMOTE_INV:
+       case SIW_OP_READ:
+       case SIW_OP_READ_LOCAL_INV:
+               if (!(wqe->sqe.flags & SIW_WQE_INLINE))
+                       siw_unref_mem_sgl(wqe->mem, wqe->sqe.num_sge);
+               break;
+
+       case SIW_OP_RECEIVE:
+               siw_unref_mem_sgl(wqe->mem, wqe->rqe.num_sge);
+               break;
+
+       case SIW_OP_READ_RESPONSE:
+               siw_unref_mem_sgl(wqe->mem, 1);
+               break;
+
+       default:
+               /*
+                * SIW_OP_INVAL_STAG and SIW_OP_REG_MR
+                * do not hold memory references
+                */
+               break;
+       }
+}
+
+int siw_invalidate_stag(struct ib_pd *pd, u32 stag)
+{
+       struct siw_device *sdev = to_siw_dev(pd->device);
+       struct siw_mem *mem = siw_mem_id2obj(sdev, stag >> 8);
+       int rv = 0;
+
+       if (unlikely(!mem)) {
+               siw_dbg_pd(pd, "STag 0x%08x unknown\n", stag);
+               return -EINVAL;
+       }
+       if (unlikely(mem->pd != pd)) {
+               siw_dbg_pd(pd, "PD mismatch for STag 0x%08x\n", stag);
+               rv = -EACCES;
+               goto out;
+       }
+       /*
+        * Per RDMA verbs definition, an STag may already be in invalid
+        * state if invalidation is requested. So no state check here.
+        */
+       mem->stag_valid = 0;
+
+       siw_dbg_pd(pd, "STag 0x%08x now invalid\n", stag);
+out:
+       siw_mem_put(mem);
+       return rv;
+}
+
+/*
+ * Gets physical address backed by PBL element. Address is referenced
+ * by linear byte offset into list of variably sized PB elements.
+ * Optionally, provides remaining len within current element, and
+ * current PBL index for later resume at same element.
+ */
+u64 siw_pbl_get_buffer(struct siw_pbl *pbl, u64 off, int *len, int *idx)
+{
+       int i = idx ? *idx : 0;
+
+       while (i < pbl->num_buf) {
+               struct siw_pble *pble = &pbl->pbe[i];
+
+               if (pble->pbl_off + pble->size > off) {
+                       u64 pble_off = off - pble->pbl_off;
+
+                       if (len)
+                               *len = pble->size - pble_off;
+                       if (idx)
+                               *idx = i;
+
+                       return pble->addr + pble_off;
+               }
+               i++;
+       }
+       if (len)
+               *len = 0;
+       return 0;
+}
+
+struct siw_pbl *siw_pbl_alloc(u32 num_buf)
+{
+       struct siw_pbl *pbl;
+       int buf_size = sizeof(*pbl);
+
+       if (num_buf == 0)
+               return ERR_PTR(-EINVAL);
+
+       buf_size += ((num_buf - 1) * sizeof(struct siw_pble));
+
+       pbl = kzalloc(buf_size, GFP_KERNEL);
+       if (!pbl)
+               return ERR_PTR(-ENOMEM);
+
+       pbl->max_buf = num_buf;
+
+       return pbl;
+}
+
+struct siw_umem *siw_umem_get(u64 start, u64 len, bool writable)
+{
+       struct siw_umem *umem;
+       struct mm_struct *mm_s;
+       u64 first_page_va;
+       unsigned long mlock_limit;
+       unsigned int foll_flags = FOLL_WRITE;
+       int num_pages, num_chunks, i, rv = 0;
+
+       if (!can_do_mlock())
+               return ERR_PTR(-EPERM);
+
+       if (!len)
+               return ERR_PTR(-EINVAL);
+
+       first_page_va = start & PAGE_MASK;
+       num_pages = PAGE_ALIGN(start + len - first_page_va) >> PAGE_SHIFT;
+       num_chunks = (num_pages >> CHUNK_SHIFT) + 1;
+
+       umem = kzalloc(sizeof(*umem), GFP_KERNEL);
+       if (!umem)
+               return ERR_PTR(-ENOMEM);
+
+       mm_s = current->mm;
+       umem->owning_mm = mm_s;
+       umem->writable = writable;
+
+       mmgrab(mm_s);
+
+       if (!writable)
+               foll_flags |= FOLL_FORCE;
+
+       down_read(&mm_s->mmap_sem);
+
+       mlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
+
+       if (num_pages + atomic64_read(&mm_s->pinned_vm) > mlock_limit) {
+               rv = -ENOMEM;
+               goto out_sem_up;
+       }
+       umem->fp_addr = first_page_va;
+
+       umem->page_chunk =
+               kcalloc(num_chunks, sizeof(struct siw_page_chunk), GFP_KERNEL);
+       if (!umem->page_chunk) {
+               rv = -ENOMEM;
+               goto out_sem_up;
+       }
+       for (i = 0; num_pages; i++) {
+               int got, nents = min_t(int, num_pages, PAGES_PER_CHUNK);
+
+               umem->page_chunk[i].plist =
+                       kcalloc(nents, sizeof(struct page *), GFP_KERNEL);
+               if (!umem->page_chunk[i].plist) {
+                       rv = -ENOMEM;
+                       goto out_sem_up;
+               }
+               got = 0;
+               while (nents) {
+                       struct page **plist = &umem->page_chunk[i].plist[got];
+
+                       rv = get_user_pages(first_page_va, nents,
+                                           foll_flags | FOLL_LONGTERM,
+                                           plist, NULL);
+                       if (rv < 0)
+                               goto out_sem_up;
+
+                       umem->num_pages += rv;
+                       atomic64_add(rv, &mm_s->pinned_vm);
+                       first_page_va += rv * PAGE_SIZE;
+                       nents -= rv;
+                       got += rv;
+               }
+               num_pages -= got;
+       }
+out_sem_up:
+       up_read(&mm_s->mmap_sem);
+
+       if (rv > 0)
+               return umem;
+
+       siw_umem_release(umem, false);
+
+       return ERR_PTR(rv);
+}
diff --git a/drivers/infiniband/sw/siw/siw_mem.h b/drivers/infiniband/sw/siw/siw_mem.h
new file mode 100644 (file)
index 0000000..f43daf2
--- /dev/null
@@ -0,0 +1,74 @@
+/* SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause */
+
+/* Authors: Bernard Metzler <bmt@zurich.ibm.com> */
+/* Copyright (c) 2008-2019, IBM Corporation */
+
+#ifndef _SIW_MEM_H
+#define _SIW_MEM_H
+
+struct siw_umem *siw_umem_get(u64 start, u64 len, bool writable);
+void siw_umem_release(struct siw_umem *umem, bool dirty);
+struct siw_pbl *siw_pbl_alloc(u32 num_buf);
+u64 siw_pbl_get_buffer(struct siw_pbl *pbl, u64 off, int *len, int *idx);
+struct siw_mem *siw_mem_id2obj(struct siw_device *sdev, int stag_index);
+int siw_mem_add(struct siw_device *sdev, struct siw_mem *m);
+int siw_invalidate_stag(struct ib_pd *pd, u32 stag);
+int siw_check_mem(struct ib_pd *pd, struct siw_mem *mem, u64 addr,
+                 enum ib_access_flags perms, int len);
+int siw_check_sge(struct ib_pd *pd, struct siw_sge *sge,
+                 struct siw_mem *mem[], enum ib_access_flags perms,
+                 u32 off, int len);
+void siw_wqe_put_mem(struct siw_wqe *wqe, enum siw_opcode op);
+int siw_mr_add_mem(struct siw_mr *mr, struct ib_pd *pd, void *mem_obj,
+                  u64 start, u64 len, int rights);
+void siw_mr_drop_mem(struct siw_mr *mr);
+void siw_free_mem(struct kref *ref);
+
+static inline void siw_mem_put(struct siw_mem *mem)
+{
+       kref_put(&mem->ref, siw_free_mem);
+}
+
+static inline struct siw_mr *siw_mem2mr(struct siw_mem *m)
+{
+       return container_of(m, struct siw_mr, mem);
+}
+
+static inline void siw_unref_mem_sgl(struct siw_mem **mem, unsigned int num_sge)
+{
+       while (num_sge) {
+               if (*mem == NULL)
+                       break;
+
+               siw_mem_put(*mem);
+               *mem = NULL;
+               mem++;
+               num_sge--;
+       }
+}
+
+#define CHUNK_SHIFT 9 /* sets number of pages per chunk */
+#define PAGES_PER_CHUNK (_AC(1, UL) << CHUNK_SHIFT)
+#define CHUNK_MASK (~(PAGES_PER_CHUNK - 1))
+#define PAGE_CHUNK_SIZE (PAGES_PER_CHUNK * sizeof(struct page *))
+
+/*
+ * siw_get_upage()
+ *
+ * Get page pointer for address on given umem.
+ *
+ * @umem: two dimensional list of page pointers
+ * @addr: user virtual address
+ */
+static inline struct page *siw_get_upage(struct siw_umem *umem, u64 addr)
+{
+       unsigned int page_idx = (addr - umem->fp_addr) >> PAGE_SHIFT,
+                    chunk_idx = page_idx >> CHUNK_SHIFT,
+                    page_in_chunk = page_idx & ~CHUNK_MASK;
+
+       if (likely(page_idx < umem->num_pages))
+               return umem->page_chunk[chunk_idx].plist[page_in_chunk];
+
+       return NULL;
+}
+#endif