Commit 2251334d authored by Bernard Metzler's avatar Bernard Metzler Committed by Jason Gunthorpe
Browse files

rdma/siw: application buffer management



Broken up commit to add the Soft iWarp RDMA driver.
Signed-off-by: default avatarBernard Metzler <bmt@zurich.ibm.com>
Signed-off-by: default avatarJason Gunthorpe <jgg@mellanox.com>
parent 303ae1cd
// 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);
}
/* 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
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment