linux/drivers/infiniband/core/umem_odp.c
Jason Gunthorpe 56ac9dd917 RDMA/umem: Avoid synchronize_srcu in the ODP MR destruction path
synchronize_rcu is slow enough that it should be avoided on the syscall
path when user space is destroying MRs. After all the rework we can now
trivially do this by having call_srcu kfree the per_mm.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2018-09-21 11:58:36 -04:00

803 lines
23 KiB
C

/*
* Copyright (c) 2014 Mellanox Technologies. All rights reserved.
*
* This software is available to you under a choice of one of two
* licenses. You may choose to be licensed under the terms of the GNU
* General Public License (GPL) Version 2, available from the file
* COPYING in the main directory of this source tree, or the
* OpenIB.org BSD license below:
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* - Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer.
*
* - Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include <linux/types.h>
#include <linux/sched.h>
#include <linux/sched/mm.h>
#include <linux/sched/task.h>
#include <linux/pid.h>
#include <linux/slab.h>
#include <linux/export.h>
#include <linux/vmalloc.h>
#include <linux/hugetlb.h>
#include <linux/interval_tree_generic.h>
#include <rdma/ib_verbs.h>
#include <rdma/ib_umem.h>
#include <rdma/ib_umem_odp.h>
/*
* The ib_umem list keeps track of memory regions for which the HW
* device request to receive notification when the related memory
* mapping is changed.
*
* ib_umem_lock protects the list.
*/
static u64 node_start(struct umem_odp_node *n)
{
struct ib_umem_odp *umem_odp =
container_of(n, struct ib_umem_odp, interval_tree);
return ib_umem_start(&umem_odp->umem);
}
/* Note that the representation of the intervals in the interval tree
* considers the ending point as contained in the interval, while the
* function ib_umem_end returns the first address which is not contained
* in the umem.
*/
static u64 node_last(struct umem_odp_node *n)
{
struct ib_umem_odp *umem_odp =
container_of(n, struct ib_umem_odp, interval_tree);
return ib_umem_end(&umem_odp->umem) - 1;
}
INTERVAL_TREE_DEFINE(struct umem_odp_node, rb, u64, __subtree_last,
node_start, node_last, static, rbt_ib_umem)
static void ib_umem_notifier_start_account(struct ib_umem_odp *umem_odp)
{
mutex_lock(&umem_odp->umem_mutex);
if (umem_odp->notifiers_count++ == 0)
/*
* Initialize the completion object for waiting on
* notifiers. Since notifier_count is zero, no one should be
* waiting right now.
*/
reinit_completion(&umem_odp->notifier_completion);
mutex_unlock(&umem_odp->umem_mutex);
}
static void ib_umem_notifier_end_account(struct ib_umem_odp *umem_odp)
{
mutex_lock(&umem_odp->umem_mutex);
/*
* This sequence increase will notify the QP page fault that the page
* that is going to be mapped in the spte could have been freed.
*/
++umem_odp->notifiers_seq;
if (--umem_odp->notifiers_count == 0)
complete_all(&umem_odp->notifier_completion);
mutex_unlock(&umem_odp->umem_mutex);
}
static int ib_umem_notifier_release_trampoline(struct ib_umem_odp *umem_odp,
u64 start, u64 end, void *cookie)
{
struct ib_umem *umem = &umem_odp->umem;
/*
* Increase the number of notifiers running, to
* prevent any further fault handling on this MR.
*/
ib_umem_notifier_start_account(umem_odp);
umem_odp->dying = 1;
/* Make sure that the fact the umem is dying is out before we release
* all pending page faults. */
smp_wmb();
complete_all(&umem_odp->notifier_completion);
umem->context->invalidate_range(umem_odp, ib_umem_start(umem),
ib_umem_end(umem));
return 0;
}
static void ib_umem_notifier_release(struct mmu_notifier *mn,
struct mm_struct *mm)
{
struct ib_ucontext_per_mm *per_mm =
container_of(mn, struct ib_ucontext_per_mm, mn);
down_read(&per_mm->umem_rwsem);
if (per_mm->active)
rbt_ib_umem_for_each_in_range(
&per_mm->umem_tree, 0, ULLONG_MAX,
ib_umem_notifier_release_trampoline, true, NULL);
up_read(&per_mm->umem_rwsem);
}
static int invalidate_page_trampoline(struct ib_umem_odp *item, u64 start,
u64 end, void *cookie)
{
ib_umem_notifier_start_account(item);
item->umem.context->invalidate_range(item, start, start + PAGE_SIZE);
ib_umem_notifier_end_account(item);
return 0;
}
static int invalidate_range_start_trampoline(struct ib_umem_odp *item,
u64 start, u64 end, void *cookie)
{
ib_umem_notifier_start_account(item);
item->umem.context->invalidate_range(item, start, end);
return 0;
}
static int ib_umem_notifier_invalidate_range_start(struct mmu_notifier *mn,
struct mm_struct *mm,
unsigned long start,
unsigned long end,
bool blockable)
{
struct ib_ucontext_per_mm *per_mm =
container_of(mn, struct ib_ucontext_per_mm, mn);
if (blockable)
down_read(&per_mm->umem_rwsem);
else if (!down_read_trylock(&per_mm->umem_rwsem))
return -EAGAIN;
if (!per_mm->active) {
up_read(&per_mm->umem_rwsem);
/*
* At this point active is permanently set and visible to this
* CPU without a lock, that fact is relied on to skip the unlock
* in range_end.
*/
return 0;
}
return rbt_ib_umem_for_each_in_range(&per_mm->umem_tree, start, end,
invalidate_range_start_trampoline,
blockable, NULL);
}
static int invalidate_range_end_trampoline(struct ib_umem_odp *item, u64 start,
u64 end, void *cookie)
{
ib_umem_notifier_end_account(item);
return 0;
}
static void ib_umem_notifier_invalidate_range_end(struct mmu_notifier *mn,
struct mm_struct *mm,
unsigned long start,
unsigned long end)
{
struct ib_ucontext_per_mm *per_mm =
container_of(mn, struct ib_ucontext_per_mm, mn);
if (unlikely(!per_mm->active))
return;
rbt_ib_umem_for_each_in_range(&per_mm->umem_tree, start,
end,
invalidate_range_end_trampoline, true, NULL);
up_read(&per_mm->umem_rwsem);
}
static const struct mmu_notifier_ops ib_umem_notifiers = {
.release = ib_umem_notifier_release,
.invalidate_range_start = ib_umem_notifier_invalidate_range_start,
.invalidate_range_end = ib_umem_notifier_invalidate_range_end,
};
static void add_umem_to_per_mm(struct ib_umem_odp *umem_odp)
{
struct ib_ucontext_per_mm *per_mm = umem_odp->per_mm;
struct ib_umem *umem = &umem_odp->umem;
down_write(&per_mm->umem_rwsem);
if (likely(ib_umem_start(umem) != ib_umem_end(umem)))
rbt_ib_umem_insert(&umem_odp->interval_tree,
&per_mm->umem_tree);
up_write(&per_mm->umem_rwsem);
}
static void remove_umem_from_per_mm(struct ib_umem_odp *umem_odp)
{
struct ib_ucontext_per_mm *per_mm = umem_odp->per_mm;
struct ib_umem *umem = &umem_odp->umem;
down_write(&per_mm->umem_rwsem);
if (likely(ib_umem_start(umem) != ib_umem_end(umem)))
rbt_ib_umem_remove(&umem_odp->interval_tree,
&per_mm->umem_tree);
complete_all(&umem_odp->notifier_completion);
up_write(&per_mm->umem_rwsem);
}
static struct ib_ucontext_per_mm *alloc_per_mm(struct ib_ucontext *ctx,
struct mm_struct *mm)
{
struct ib_ucontext_per_mm *per_mm;
int ret;
per_mm = kzalloc(sizeof(*per_mm), GFP_KERNEL);
if (!per_mm)
return ERR_PTR(-ENOMEM);
per_mm->context = ctx;
per_mm->mm = mm;
per_mm->umem_tree = RB_ROOT_CACHED;
init_rwsem(&per_mm->umem_rwsem);
per_mm->active = ctx->invalidate_range;
rcu_read_lock();
per_mm->tgid = get_task_pid(current->group_leader, PIDTYPE_PID);
rcu_read_unlock();
WARN_ON(mm != current->mm);
per_mm->mn.ops = &ib_umem_notifiers;
ret = mmu_notifier_register(&per_mm->mn, per_mm->mm);
if (ret) {
dev_err(&ctx->device->dev,
"Failed to register mmu_notifier %d\n", ret);
goto out_pid;
}
list_add(&per_mm->ucontext_list, &ctx->per_mm_list);
return per_mm;
out_pid:
put_pid(per_mm->tgid);
kfree(per_mm);
return ERR_PTR(ret);
}
static int get_per_mm(struct ib_umem_odp *umem_odp)
{
struct ib_ucontext *ctx = umem_odp->umem.context;
struct ib_ucontext_per_mm *per_mm;
/*
* Generally speaking we expect only one or two per_mm in this list,
* so no reason to optimize this search today.
*/
mutex_lock(&ctx->per_mm_list_lock);
list_for_each_entry(per_mm, &ctx->per_mm_list, ucontext_list) {
if (per_mm->mm == umem_odp->umem.owning_mm)
goto found;
}
per_mm = alloc_per_mm(ctx, umem_odp->umem.owning_mm);
if (IS_ERR(per_mm)) {
mutex_unlock(&ctx->per_mm_list_lock);
return PTR_ERR(per_mm);
}
found:
umem_odp->per_mm = per_mm;
per_mm->odp_mrs_count++;
mutex_unlock(&ctx->per_mm_list_lock);
return 0;
}
static void free_per_mm(struct rcu_head *rcu)
{
kfree(container_of(rcu, struct ib_ucontext_per_mm, rcu));
}
void put_per_mm(struct ib_umem_odp *umem_odp)
{
struct ib_ucontext_per_mm *per_mm = umem_odp->per_mm;
struct ib_ucontext *ctx = umem_odp->umem.context;
bool need_free;
mutex_lock(&ctx->per_mm_list_lock);
umem_odp->per_mm = NULL;
per_mm->odp_mrs_count--;
need_free = per_mm->odp_mrs_count == 0;
if (need_free)
list_del(&per_mm->ucontext_list);
mutex_unlock(&ctx->per_mm_list_lock);
if (!need_free)
return;
/*
* NOTE! mmu_notifier_unregister() can happen between a start/end
* callback, resulting in an start/end, and thus an unbalanced
* lock. This doesn't really matter to us since we are about to kfree
* the memory that holds the lock, however LOCKDEP doesn't like this.
*/
down_write(&per_mm->umem_rwsem);
per_mm->active = false;
up_write(&per_mm->umem_rwsem);
WARN_ON(!RB_EMPTY_ROOT(&per_mm->umem_tree.rb_root));
mmu_notifier_unregister_no_release(&per_mm->mn, per_mm->mm);
put_pid(per_mm->tgid);
mmu_notifier_call_srcu(&per_mm->rcu, free_per_mm);
}
struct ib_umem_odp *ib_alloc_odp_umem(struct ib_ucontext_per_mm *per_mm,
unsigned long addr, size_t size)
{
struct ib_ucontext *ctx = per_mm->context;
struct ib_umem_odp *odp_data;
struct ib_umem *umem;
int pages = size >> PAGE_SHIFT;
int ret;
odp_data = kzalloc(sizeof(*odp_data), GFP_KERNEL);
if (!odp_data)
return ERR_PTR(-ENOMEM);
umem = &odp_data->umem;
umem->context = ctx;
umem->length = size;
umem->address = addr;
umem->page_shift = PAGE_SHIFT;
umem->writable = 1;
umem->is_odp = 1;
odp_data->per_mm = per_mm;
mutex_init(&odp_data->umem_mutex);
init_completion(&odp_data->notifier_completion);
odp_data->page_list =
vzalloc(array_size(pages, sizeof(*odp_data->page_list)));
if (!odp_data->page_list) {
ret = -ENOMEM;
goto out_odp_data;
}
odp_data->dma_list =
vzalloc(array_size(pages, sizeof(*odp_data->dma_list)));
if (!odp_data->dma_list) {
ret = -ENOMEM;
goto out_page_list;
}
/*
* Caller must ensure that the umem_odp that the per_mm came from
* cannot be freed during the call to ib_alloc_odp_umem.
*/
mutex_lock(&ctx->per_mm_list_lock);
per_mm->odp_mrs_count++;
mutex_unlock(&ctx->per_mm_list_lock);
add_umem_to_per_mm(odp_data);
return odp_data;
out_page_list:
vfree(odp_data->page_list);
out_odp_data:
kfree(odp_data);
return ERR_PTR(ret);
}
EXPORT_SYMBOL(ib_alloc_odp_umem);
int ib_umem_odp_get(struct ib_umem_odp *umem_odp, int access)
{
struct ib_umem *umem = &umem_odp->umem;
/*
* NOTE: This must called in a process context where umem->owning_mm
* == current->mm
*/
struct mm_struct *mm = umem->owning_mm;
int ret_val;
if (access & IB_ACCESS_HUGETLB) {
struct vm_area_struct *vma;
struct hstate *h;
down_read(&mm->mmap_sem);
vma = find_vma(mm, ib_umem_start(umem));
if (!vma || !is_vm_hugetlb_page(vma)) {
up_read(&mm->mmap_sem);
return -EINVAL;
}
h = hstate_vma(vma);
umem->page_shift = huge_page_shift(h);
up_read(&mm->mmap_sem);
umem->hugetlb = 1;
} else {
umem->hugetlb = 0;
}
mutex_init(&umem_odp->umem_mutex);
init_completion(&umem_odp->notifier_completion);
if (ib_umem_num_pages(umem)) {
umem_odp->page_list =
vzalloc(array_size(sizeof(*umem_odp->page_list),
ib_umem_num_pages(umem)));
if (!umem_odp->page_list)
return -ENOMEM;
umem_odp->dma_list =
vzalloc(array_size(sizeof(*umem_odp->dma_list),
ib_umem_num_pages(umem)));
if (!umem_odp->dma_list) {
ret_val = -ENOMEM;
goto out_page_list;
}
}
ret_val = get_per_mm(umem_odp);
if (ret_val)
goto out_dma_list;
add_umem_to_per_mm(umem_odp);
return 0;
out_dma_list:
vfree(umem_odp->dma_list);
out_page_list:
vfree(umem_odp->page_list);
return ret_val;
}
void ib_umem_odp_release(struct ib_umem_odp *umem_odp)
{
struct ib_umem *umem = &umem_odp->umem;
/*
* Ensure that no more pages are mapped in the umem.
*
* It is the driver's responsibility to ensure, before calling us,
* that the hardware will not attempt to access the MR any more.
*/
ib_umem_odp_unmap_dma_pages(umem_odp, ib_umem_start(umem),
ib_umem_end(umem));
remove_umem_from_per_mm(umem_odp);
put_per_mm(umem_odp);
vfree(umem_odp->dma_list);
vfree(umem_odp->page_list);
}
/*
* Map for DMA and insert a single page into the on-demand paging page tables.
*
* @umem: the umem to insert the page to.
* @page_index: index in the umem to add the page to.
* @page: the page struct to map and add.
* @access_mask: access permissions needed for this page.
* @current_seq: sequence number for synchronization with invalidations.
* the sequence number is taken from
* umem_odp->notifiers_seq.
*
* The function returns -EFAULT if the DMA mapping operation fails. It returns
* -EAGAIN if a concurrent invalidation prevents us from updating the page.
*
* The page is released via put_page even if the operation failed. For
* on-demand pinning, the page is released whenever it isn't stored in the
* umem.
*/
static int ib_umem_odp_map_dma_single_page(
struct ib_umem_odp *umem_odp,
int page_index,
struct page *page,
u64 access_mask,
unsigned long current_seq)
{
struct ib_umem *umem = &umem_odp->umem;
struct ib_device *dev = umem->context->device;
dma_addr_t dma_addr;
int stored_page = 0;
int remove_existing_mapping = 0;
int ret = 0;
/*
* Note: we avoid writing if seq is different from the initial seq, to
* handle case of a racing notifier. This check also allows us to bail
* early if we have a notifier running in parallel with us.
*/
if (ib_umem_mmu_notifier_retry(umem_odp, current_seq)) {
ret = -EAGAIN;
goto out;
}
if (!(umem_odp->dma_list[page_index])) {
dma_addr = ib_dma_map_page(dev,
page,
0, BIT(umem->page_shift),
DMA_BIDIRECTIONAL);
if (ib_dma_mapping_error(dev, dma_addr)) {
ret = -EFAULT;
goto out;
}
umem_odp->dma_list[page_index] = dma_addr | access_mask;
umem_odp->page_list[page_index] = page;
umem->npages++;
stored_page = 1;
} else if (umem_odp->page_list[page_index] == page) {
umem_odp->dma_list[page_index] |= access_mask;
} else {
pr_err("error: got different pages in IB device and from get_user_pages. IB device page: %p, gup page: %p\n",
umem_odp->page_list[page_index], page);
/* Better remove the mapping now, to prevent any further
* damage. */
remove_existing_mapping = 1;
}
out:
/* On Demand Paging - avoid pinning the page */
if (umem->context->invalidate_range || !stored_page)
put_page(page);
if (remove_existing_mapping && umem->context->invalidate_range) {
invalidate_page_trampoline(
umem_odp,
ib_umem_start(umem) + (page_index >> umem->page_shift),
ib_umem_start(umem) + ((page_index + 1) >>
umem->page_shift),
NULL);
ret = -EAGAIN;
}
return ret;
}
/**
* ib_umem_odp_map_dma_pages - Pin and DMA map userspace memory in an ODP MR.
*
* Pins the range of pages passed in the argument, and maps them to
* DMA addresses. The DMA addresses of the mapped pages is updated in
* umem_odp->dma_list.
*
* Returns the number of pages mapped in success, negative error code
* for failure.
* An -EAGAIN error code is returned when a concurrent mmu notifier prevents
* the function from completing its task.
* An -ENOENT error code indicates that userspace process is being terminated
* and mm was already destroyed.
* @umem_odp: the umem to map and pin
* @user_virt: the address from which we need to map.
* @bcnt: the minimal number of bytes to pin and map. The mapping might be
* bigger due to alignment, and may also be smaller in case of an error
* pinning or mapping a page. The actual pages mapped is returned in
* the return value.
* @access_mask: bit mask of the requested access permissions for the given
* range.
* @current_seq: the MMU notifiers sequance value for synchronization with
* invalidations. the sequance number is read from
* umem_odp->notifiers_seq before calling this function
*/
int ib_umem_odp_map_dma_pages(struct ib_umem_odp *umem_odp, u64 user_virt,
u64 bcnt, u64 access_mask,
unsigned long current_seq)
{
struct ib_umem *umem = &umem_odp->umem;
struct task_struct *owning_process = NULL;
struct mm_struct *owning_mm = umem_odp->umem.owning_mm;
struct page **local_page_list = NULL;
u64 page_mask, off;
int j, k, ret = 0, start_idx, npages = 0, page_shift;
unsigned int flags = 0;
phys_addr_t p = 0;
if (access_mask == 0)
return -EINVAL;
if (user_virt < ib_umem_start(umem) ||
user_virt + bcnt > ib_umem_end(umem))
return -EFAULT;
local_page_list = (struct page **)__get_free_page(GFP_KERNEL);
if (!local_page_list)
return -ENOMEM;
page_shift = umem->page_shift;
page_mask = ~(BIT(page_shift) - 1);
off = user_virt & (~page_mask);
user_virt = user_virt & page_mask;
bcnt += off; /* Charge for the first page offset as well. */
/*
* owning_process is allowed to be NULL, this means somehow the mm is
* existing beyond the lifetime of the originating process.. Presumably
* mmget_not_zero will fail in this case.
*/
owning_process = get_pid_task(umem_odp->per_mm->tgid, PIDTYPE_PID);
if (WARN_ON(!mmget_not_zero(umem_odp->umem.owning_mm))) {
ret = -EINVAL;
goto out_put_task;
}
if (access_mask & ODP_WRITE_ALLOWED_BIT)
flags |= FOLL_WRITE;
start_idx = (user_virt - ib_umem_start(umem)) >> page_shift;
k = start_idx;
while (bcnt > 0) {
const size_t gup_num_pages = min_t(size_t,
(bcnt + BIT(page_shift) - 1) >> page_shift,
PAGE_SIZE / sizeof(struct page *));
down_read(&owning_mm->mmap_sem);
/*
* Note: this might result in redundent page getting. We can
* avoid this by checking dma_list to be 0 before calling
* get_user_pages. However, this make the code much more
* complex (and doesn't gain us much performance in most use
* cases).
*/
npages = get_user_pages_remote(owning_process, owning_mm,
user_virt, gup_num_pages,
flags, local_page_list, NULL, NULL);
up_read(&owning_mm->mmap_sem);
if (npages < 0)
break;
bcnt -= min_t(size_t, npages << PAGE_SHIFT, bcnt);
mutex_lock(&umem_odp->umem_mutex);
for (j = 0; j < npages; j++, user_virt += PAGE_SIZE) {
if (user_virt & ~page_mask) {
p += PAGE_SIZE;
if (page_to_phys(local_page_list[j]) != p) {
ret = -EFAULT;
break;
}
put_page(local_page_list[j]);
continue;
}
ret = ib_umem_odp_map_dma_single_page(
umem_odp, k, local_page_list[j],
access_mask, current_seq);
if (ret < 0)
break;
p = page_to_phys(local_page_list[j]);
k++;
}
mutex_unlock(&umem_odp->umem_mutex);
if (ret < 0) {
/* Release left over pages when handling errors. */
for (++j; j < npages; ++j)
put_page(local_page_list[j]);
break;
}
}
if (ret >= 0) {
if (npages < 0 && k == start_idx)
ret = npages;
else
ret = k - start_idx;
}
mmput(owning_mm);
out_put_task:
if (owning_process)
put_task_struct(owning_process);
free_page((unsigned long)local_page_list);
return ret;
}
EXPORT_SYMBOL(ib_umem_odp_map_dma_pages);
void ib_umem_odp_unmap_dma_pages(struct ib_umem_odp *umem_odp, u64 virt,
u64 bound)
{
struct ib_umem *umem = &umem_odp->umem;
int idx;
u64 addr;
struct ib_device *dev = umem->context->device;
virt = max_t(u64, virt, ib_umem_start(umem));
bound = min_t(u64, bound, ib_umem_end(umem));
/* Note that during the run of this function, the
* notifiers_count of the MR is > 0, preventing any racing
* faults from completion. We might be racing with other
* invalidations, so we must make sure we free each page only
* once. */
mutex_lock(&umem_odp->umem_mutex);
for (addr = virt; addr < bound; addr += BIT(umem->page_shift)) {
idx = (addr - ib_umem_start(umem)) >> umem->page_shift;
if (umem_odp->page_list[idx]) {
struct page *page = umem_odp->page_list[idx];
dma_addr_t dma = umem_odp->dma_list[idx];
dma_addr_t dma_addr = dma & ODP_DMA_ADDR_MASK;
WARN_ON(!dma_addr);
ib_dma_unmap_page(dev, dma_addr, PAGE_SIZE,
DMA_BIDIRECTIONAL);
if (dma & ODP_WRITE_ALLOWED_BIT) {
struct page *head_page = compound_head(page);
/*
* set_page_dirty prefers being called with
* the page lock. However, MMU notifiers are
* called sometimes with and sometimes without
* the lock. We rely on the umem_mutex instead
* to prevent other mmu notifiers from
* continuing and allowing the page mapping to
* be removed.
*/
set_page_dirty(head_page);
}
/* on demand pinning support */
if (!umem->context->invalidate_range)
put_page(page);
umem_odp->page_list[idx] = NULL;
umem_odp->dma_list[idx] = 0;
umem->npages--;
}
}
mutex_unlock(&umem_odp->umem_mutex);
}
EXPORT_SYMBOL(ib_umem_odp_unmap_dma_pages);
/* @last is not a part of the interval. See comment for function
* node_last.
*/
int rbt_ib_umem_for_each_in_range(struct rb_root_cached *root,
u64 start, u64 last,
umem_call_back cb,
bool blockable,
void *cookie)
{
int ret_val = 0;
struct umem_odp_node *node, *next;
struct ib_umem_odp *umem;
if (unlikely(start == last))
return ret_val;
for (node = rbt_ib_umem_iter_first(root, start, last - 1);
node; node = next) {
/* TODO move the blockable decision up to the callback */
if (!blockable)
return -EAGAIN;
next = rbt_ib_umem_iter_next(node, start, last - 1);
umem = container_of(node, struct ib_umem_odp, interval_tree);
ret_val = cb(umem, start, last, cookie) || ret_val;
}
return ret_val;
}
EXPORT_SYMBOL(rbt_ib_umem_for_each_in_range);
struct ib_umem_odp *rbt_ib_umem_lookup(struct rb_root_cached *root,
u64 addr, u64 length)
{
struct umem_odp_node *node;
node = rbt_ib_umem_iter_first(root, addr, addr + length - 1);
if (node)
return container_of(node, struct ib_umem_odp, interval_tree);
return NULL;
}
EXPORT_SYMBOL(rbt_ib_umem_lookup);