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-rw-r--r--drivers/misc/mic/scif/scif_rma.c1770
1 files changed, 1770 insertions, 0 deletions
diff --git a/drivers/misc/mic/scif/scif_rma.c b/drivers/misc/mic/scif/scif_rma.c
new file mode 100644
index 000000000000..e2889967036a
--- /dev/null
+++ b/drivers/misc/mic/scif/scif_rma.c
@@ -0,0 +1,1770 @@
+/*
+ * Intel MIC Platform Software Stack (MPSS)
+ *
+ * Copyright(c) 2015 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * Intel SCIF driver.
+ *
+ */
+#include <linux/dma_remapping.h>
+#include <linux/pagemap.h>
+#include "scif_main.h"
+#include "scif_map.h"
+
+/* Used to skip ulimit checks for registrations with SCIF_MAP_KERNEL flag */
+#define SCIF_MAP_ULIMIT 0x40
+
+bool scif_ulimit_check = 1;
+
+/**
+ * scif_rma_ep_init:
+ * @ep: end point
+ *
+ * Initialize RMA per EP data structures.
+ */
+void scif_rma_ep_init(struct scif_endpt *ep)
+{
+ struct scif_endpt_rma_info *rma = &ep->rma_info;
+
+ mutex_init(&rma->rma_lock);
+ init_iova_domain(&rma->iovad, PAGE_SIZE, SCIF_IOVA_START_PFN,
+ SCIF_DMA_64BIT_PFN);
+ spin_lock_init(&rma->tc_lock);
+ mutex_init(&rma->mmn_lock);
+ INIT_LIST_HEAD(&rma->reg_list);
+ INIT_LIST_HEAD(&rma->remote_reg_list);
+ atomic_set(&rma->tw_refcount, 0);
+ atomic_set(&rma->tcw_refcount, 0);
+ atomic_set(&rma->tcw_total_pages, 0);
+ atomic_set(&rma->fence_refcount, 0);
+
+ rma->async_list_del = 0;
+ rma->dma_chan = NULL;
+ INIT_LIST_HEAD(&rma->mmn_list);
+ INIT_LIST_HEAD(&rma->vma_list);
+ init_waitqueue_head(&rma->markwq);
+}
+
+/**
+ * scif_rma_ep_can_uninit:
+ * @ep: end point
+ *
+ * Returns 1 if an endpoint can be uninitialized and 0 otherwise.
+ */
+int scif_rma_ep_can_uninit(struct scif_endpt *ep)
+{
+ int ret = 0;
+
+ mutex_lock(&ep->rma_info.rma_lock);
+ /* Destroy RMA Info only if both lists are empty */
+ if (list_empty(&ep->rma_info.reg_list) &&
+ list_empty(&ep->rma_info.remote_reg_list) &&
+ list_empty(&ep->rma_info.mmn_list) &&
+ !atomic_read(&ep->rma_info.tw_refcount) &&
+ !atomic_read(&ep->rma_info.tcw_refcount) &&
+ !atomic_read(&ep->rma_info.fence_refcount))
+ ret = 1;
+ mutex_unlock(&ep->rma_info.rma_lock);
+ return ret;
+}
+
+/**
+ * scif_create_pinned_pages:
+ * @nr_pages: number of pages in window
+ * @prot: read/write protection
+ *
+ * Allocate and prepare a set of pinned pages.
+ */
+static struct scif_pinned_pages *
+scif_create_pinned_pages(int nr_pages, int prot)
+{
+ struct scif_pinned_pages *pin;
+
+ might_sleep();
+ pin = scif_zalloc(sizeof(*pin));
+ if (!pin)
+ goto error;
+
+ pin->pages = scif_zalloc(nr_pages * sizeof(*pin->pages));
+ if (!pin->pages)
+ goto error_free_pinned_pages;
+
+ pin->prot = prot;
+ pin->magic = SCIFEP_MAGIC;
+ return pin;
+
+error_free_pinned_pages:
+ scif_free(pin, sizeof(*pin));
+error:
+ return NULL;
+}
+
+/**
+ * scif_destroy_pinned_pages:
+ * @pin: A set of pinned pages.
+ *
+ * Deallocate resources for pinned pages.
+ */
+static int scif_destroy_pinned_pages(struct scif_pinned_pages *pin)
+{
+ int j;
+ int writeable = pin->prot & SCIF_PROT_WRITE;
+ int kernel = SCIF_MAP_KERNEL & pin->map_flags;
+
+ for (j = 0; j < pin->nr_pages; j++) {
+ if (pin->pages[j] && !kernel) {
+ if (writeable)
+ SetPageDirty(pin->pages[j]);
+ put_page(pin->pages[j]);
+ }
+ }
+
+ scif_free(pin->pages,
+ pin->nr_pages * sizeof(*pin->pages));
+ scif_free(pin, sizeof(*pin));
+ return 0;
+}
+
+/*
+ * scif_create_window:
+ * @ep: end point
+ * @nr_pages: number of pages
+ * @offset: registration offset
+ * @temp: true if a temporary window is being created
+ *
+ * Allocate and prepare a self registration window.
+ */
+struct scif_window *scif_create_window(struct scif_endpt *ep, int nr_pages,
+ s64 offset, bool temp)
+{
+ struct scif_window *window;
+
+ might_sleep();
+ window = scif_zalloc(sizeof(*window));
+ if (!window)
+ goto error;
+
+ window->dma_addr = scif_zalloc(nr_pages * sizeof(*window->dma_addr));
+ if (!window->dma_addr)
+ goto error_free_window;
+
+ window->num_pages = scif_zalloc(nr_pages * sizeof(*window->num_pages));
+ if (!window->num_pages)
+ goto error_free_window;
+
+ window->offset = offset;
+ window->ep = (u64)ep;
+ window->magic = SCIFEP_MAGIC;
+ window->reg_state = OP_IDLE;
+ init_waitqueue_head(&window->regwq);
+ window->unreg_state = OP_IDLE;
+ init_waitqueue_head(&window->unregwq);
+ INIT_LIST_HEAD(&window->list);
+ window->type = SCIF_WINDOW_SELF;
+ window->temp = temp;
+ return window;
+
+error_free_window:
+ scif_free(window->dma_addr,
+ nr_pages * sizeof(*window->dma_addr));
+ scif_free(window, sizeof(*window));
+error:
+ return NULL;
+}
+
+/**
+ * scif_destroy_incomplete_window:
+ * @ep: end point
+ * @window: registration window
+ *
+ * Deallocate resources for self window.
+ */
+static void scif_destroy_incomplete_window(struct scif_endpt *ep,
+ struct scif_window *window)
+{
+ int err;
+ int nr_pages = window->nr_pages;
+ struct scif_allocmsg *alloc = &window->alloc_handle;
+ struct scifmsg msg;
+
+retry:
+ /* Wait for a SCIF_ALLOC_GNT/REJ message */
+ err = wait_event_timeout(alloc->allocwq,
+ alloc->state != OP_IN_PROGRESS,
+ SCIF_NODE_ALIVE_TIMEOUT);
+ if (!err && scifdev_alive(ep))
+ goto retry;
+
+ mutex_lock(&ep->rma_info.rma_lock);
+ if (alloc->state == OP_COMPLETED) {
+ msg.uop = SCIF_FREE_VIRT;
+ msg.src = ep->port;
+ msg.payload[0] = ep->remote_ep;
+ msg.payload[1] = window->alloc_handle.vaddr;
+ msg.payload[2] = (u64)window;
+ msg.payload[3] = SCIF_REGISTER;
+ _scif_nodeqp_send(ep->remote_dev, &msg);
+ }
+ mutex_unlock(&ep->rma_info.rma_lock);
+
+ scif_free_window_offset(ep, window, window->offset);
+ scif_free(window->dma_addr, nr_pages * sizeof(*window->dma_addr));
+ scif_free(window->num_pages, nr_pages * sizeof(*window->num_pages));
+ scif_free(window, sizeof(*window));
+}
+
+/**
+ * scif_unmap_window:
+ * @remote_dev: SCIF remote device
+ * @window: registration window
+ *
+ * Delete any DMA mappings created for a registered self window
+ */
+void scif_unmap_window(struct scif_dev *remote_dev, struct scif_window *window)
+{
+ int j;
+
+ if (scif_is_iommu_enabled() && !scifdev_self(remote_dev)) {
+ if (window->st) {
+ dma_unmap_sg(&remote_dev->sdev->dev,
+ window->st->sgl, window->st->nents,
+ DMA_BIDIRECTIONAL);
+ sg_free_table(window->st);
+ kfree(window->st);
+ window->st = NULL;
+ }
+ } else {
+ for (j = 0; j < window->nr_contig_chunks; j++) {
+ if (window->dma_addr[j]) {
+ scif_unmap_single(window->dma_addr[j],
+ remote_dev,
+ window->num_pages[j] <<
+ PAGE_SHIFT);
+ window->dma_addr[j] = 0x0;
+ }
+ }
+ }
+}
+
+static inline struct mm_struct *__scif_acquire_mm(void)
+{
+ if (scif_ulimit_check)
+ return get_task_mm(current);
+ return NULL;
+}
+
+static inline void __scif_release_mm(struct mm_struct *mm)
+{
+ if (mm)
+ mmput(mm);
+}
+
+static inline int
+__scif_dec_pinned_vm_lock(struct mm_struct *mm,
+ int nr_pages, bool try_lock)
+{
+ if (!mm || !nr_pages || !scif_ulimit_check)
+ return 0;
+ if (try_lock) {
+ if (!down_write_trylock(&mm->mmap_sem)) {
+ dev_err(scif_info.mdev.this_device,
+ "%s %d err\n", __func__, __LINE__);
+ return -1;
+ }
+ } else {
+ down_write(&mm->mmap_sem);
+ }
+ mm->pinned_vm -= nr_pages;
+ up_write(&mm->mmap_sem);
+ return 0;
+}
+
+static inline int __scif_check_inc_pinned_vm(struct mm_struct *mm,
+ int nr_pages)
+{
+ unsigned long locked, lock_limit;
+
+ if (!mm || !nr_pages || !scif_ulimit_check)
+ return 0;
+
+ locked = nr_pages;
+ locked += mm->pinned_vm;
+ lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
+ if ((locked > lock_limit) && !capable(CAP_IPC_LOCK)) {
+ dev_err(scif_info.mdev.this_device,
+ "locked(%lu) > lock_limit(%lu)\n",
+ locked, lock_limit);
+ return -ENOMEM;
+ }
+ mm->pinned_vm = locked;
+ return 0;
+}
+
+/**
+ * scif_destroy_window:
+ * @ep: end point
+ * @window: registration window
+ *
+ * Deallocate resources for self window.
+ */
+int scif_destroy_window(struct scif_endpt *ep, struct scif_window *window)
+{
+ int j;
+ struct scif_pinned_pages *pinned_pages = window->pinned_pages;
+ int nr_pages = window->nr_pages;
+
+ might_sleep();
+ if (!window->temp && window->mm) {
+ __scif_dec_pinned_vm_lock(window->mm, window->nr_pages, 0);
+ __scif_release_mm(window->mm);
+ window->mm = NULL;
+ }
+
+ scif_free_window_offset(ep, window, window->offset);
+ scif_unmap_window(ep->remote_dev, window);
+ /*
+ * Decrement references for this set of pinned pages from
+ * this window.
+ */
+ j = atomic_sub_return(1, &pinned_pages->ref_count);
+ if (j < 0)
+ dev_err(scif_info.mdev.this_device,
+ "%s %d incorrect ref count %d\n",
+ __func__, __LINE__, j);
+ /*
+ * If the ref count for pinned_pages is zero then someone
+ * has already called scif_unpin_pages() for it and we should
+ * destroy the page cache.
+ */
+ if (!j)
+ scif_destroy_pinned_pages(window->pinned_pages);
+ scif_free(window->dma_addr, nr_pages * sizeof(*window->dma_addr));
+ scif_free(window->num_pages, nr_pages * sizeof(*window->num_pages));
+ window->magic = 0;
+ scif_free(window, sizeof(*window));
+ return 0;
+}
+
+/**
+ * scif_create_remote_lookup:
+ * @remote_dev: SCIF remote device
+ * @window: remote window
+ *
+ * Allocate and prepare lookup entries for the remote
+ * end to copy over the physical addresses.
+ * Returns 0 on success and appropriate errno on failure.
+ */
+static int scif_create_remote_lookup(struct scif_dev *remote_dev,
+ struct scif_window *window)
+{
+ int i, j, err = 0;
+ int nr_pages = window->nr_pages;
+ bool vmalloc_dma_phys, vmalloc_num_pages;
+
+ might_sleep();
+ /* Map window */
+ err = scif_map_single(&window->mapped_offset,
+ window, remote_dev, sizeof(*window));
+ if (err)
+ goto error_window;
+
+ /* Compute the number of lookup entries. 21 == 2MB Shift */
+ window->nr_lookup = ALIGN(nr_pages * PAGE_SIZE,
+ ((2) * 1024 * 1024)) >> 21;
+
+ window->dma_addr_lookup.lookup =
+ scif_alloc_coherent(&window->dma_addr_lookup.offset,
+ remote_dev, window->nr_lookup *
+ sizeof(*window->dma_addr_lookup.lookup),
+ GFP_KERNEL | __GFP_ZERO);
+ if (!window->dma_addr_lookup.lookup)
+ goto error_window;
+
+ window->num_pages_lookup.lookup =
+ scif_alloc_coherent(&window->num_pages_lookup.offset,
+ remote_dev, window->nr_lookup *
+ sizeof(*window->num_pages_lookup.lookup),
+ GFP_KERNEL | __GFP_ZERO);
+ if (!window->num_pages_lookup.lookup)
+ goto error_window;
+
+ vmalloc_dma_phys = is_vmalloc_addr(&window->dma_addr[0]);
+ vmalloc_num_pages = is_vmalloc_addr(&window->num_pages[0]);
+
+ /* Now map each of the pages containing physical addresses */
+ for (i = 0, j = 0; i < nr_pages; i += SCIF_NR_ADDR_IN_PAGE, j++) {
+ err = scif_map_page(&window->dma_addr_lookup.lookup[j],
+ vmalloc_dma_phys ?
+ vmalloc_to_page(&window->dma_addr[i]) :
+ virt_to_page(&window->dma_addr[i]),
+ remote_dev);
+ if (err)
+ goto error_window;
+ err = scif_map_page(&window->num_pages_lookup.lookup[j],
+ vmalloc_dma_phys ?
+ vmalloc_to_page(&window->num_pages[i]) :
+ virt_to_page(&window->num_pages[i]),
+ remote_dev);
+ if (err)
+ goto error_window;
+ }
+ return 0;
+error_window:
+ return err;
+}
+
+/**
+ * scif_destroy_remote_lookup:
+ * @remote_dev: SCIF remote device
+ * @window: remote window
+ *
+ * Destroy lookup entries used for the remote
+ * end to copy over the physical addresses.
+ */
+static void scif_destroy_remote_lookup(struct scif_dev *remote_dev,
+ struct scif_window *window)
+{
+ int i, j;
+
+ if (window->nr_lookup) {
+ struct scif_rma_lookup *lup = &window->dma_addr_lookup;
+ struct scif_rma_lookup *npup = &window->num_pages_lookup;
+
+ for (i = 0, j = 0; i < window->nr_pages;
+ i += SCIF_NR_ADDR_IN_PAGE, j++) {
+ if (lup->lookup && lup->lookup[j])
+ scif_unmap_single(lup->lookup[j],
+ remote_dev,
+ PAGE_SIZE);
+ if (npup->lookup && npup->lookup[j])
+ scif_unmap_single(npup->lookup[j],
+ remote_dev,
+ PAGE_SIZE);
+ }
+ if (lup->lookup)
+ scif_free_coherent(lup->lookup, lup->offset,
+ remote_dev, window->nr_lookup *
+ sizeof(*lup->lookup));
+ if (npup->lookup)
+ scif_free_coherent(npup->lookup, npup->offset,
+ remote_dev, window->nr_lookup *
+ sizeof(*npup->lookup));
+ if (window->mapped_offset)
+ scif_unmap_single(window->mapped_offset,
+ remote_dev, sizeof(*window));
+ window->nr_lookup = 0;
+ }
+}
+
+/**
+ * scif_create_remote_window:
+ * @ep: end point
+ * @nr_pages: number of pages in window
+ *
+ * Allocate and prepare a remote registration window.
+ */
+static struct scif_window *
+scif_create_remote_window(struct scif_dev *scifdev, int nr_pages)
+{
+ struct scif_window *window;
+
+ might_sleep();
+ window = scif_zalloc(sizeof(*window));
+ if (!window)
+ goto error_ret;
+
+ window->magic = SCIFEP_MAGIC;
+ window->nr_pages = nr_pages;
+
+ window->dma_addr = scif_zalloc(nr_pages * sizeof(*window->dma_addr));
+ if (!window->dma_addr)
+ goto error_window;
+
+ window->num_pages = scif_zalloc(nr_pages *
+ sizeof(*window->num_pages));
+ if (!window->num_pages)
+ goto error_window;
+
+ if (scif_create_remote_lookup(scifdev, window))
+ goto error_window;
+
+ window->type = SCIF_WINDOW_PEER;
+ window->unreg_state = OP_IDLE;
+ INIT_LIST_HEAD(&window->list);
+ return window;
+error_window:
+ scif_destroy_remote_window(window);
+error_ret:
+ return NULL;
+}
+
+/**
+ * scif_destroy_remote_window:
+ * @ep: end point
+ * @window: remote registration window
+ *
+ * Deallocate resources for remote window.
+ */
+void
+scif_destroy_remote_window(struct scif_window *window)
+{
+ scif_free(window->dma_addr, window->nr_pages *
+ sizeof(*window->dma_addr));
+ scif_free(window->num_pages, window->nr_pages *
+ sizeof(*window->num_pages));
+ window->magic = 0;
+ scif_free(window, sizeof(*window));
+}
+
+/**
+ * scif_iommu_map: create DMA mappings if the IOMMU is enabled
+ * @remote_dev: SCIF remote device
+ * @window: remote registration window
+ *
+ * Map the physical pages using dma_map_sg(..) and then detect the number
+ * of contiguous DMA mappings allocated
+ */
+static int scif_iommu_map(struct scif_dev *remote_dev,
+ struct scif_window *window)
+{
+ struct scatterlist *sg;
+ int i, err;
+ scif_pinned_pages_t pin = window->pinned_pages;
+
+ window->st = kzalloc(sizeof(*window->st), GFP_KERNEL);
+ if (!window->st)
+ return -ENOMEM;
+
+ err = sg_alloc_table(window->st, window->nr_pages, GFP_KERNEL);
+ if (err)
+ return err;
+
+ for_each_sg(window->st->sgl, sg, window->st->nents, i)
+ sg_set_page(sg, pin->pages[i], PAGE_SIZE, 0x0);
+
+ err = dma_map_sg(&remote_dev->sdev->dev, window->st->sgl,
+ window->st->nents, DMA_BIDIRECTIONAL);
+ if (!err)
+ return -ENOMEM;
+ /* Detect contiguous ranges of DMA mappings */
+ sg = window->st->sgl;
+ for (i = 0; sg; i++) {
+ dma_addr_t last_da;
+
+ window->dma_addr[i] = sg_dma_address(sg);
+ window->num_pages[i] = sg_dma_len(sg) >> PAGE_SHIFT;
+ last_da = sg_dma_address(sg) + sg_dma_len(sg);
+ while ((sg = sg_next(sg)) && sg_dma_address(sg) == last_da) {
+ window->num_pages[i] +=
+ (sg_dma_len(sg) >> PAGE_SHIFT);
+ last_da = window->dma_addr[i] +
+ sg_dma_len(sg);
+ }
+ window->nr_contig_chunks++;
+ }
+ return 0;
+}
+
+/**
+ * scif_map_window:
+ * @remote_dev: SCIF remote device
+ * @window: self registration window
+ *
+ * Map pages of a window into the aperture/PCI.
+ * Also determine addresses required for DMA.
+ */
+int
+scif_map_window(struct scif_dev *remote_dev, struct scif_window *window)
+{
+ int i, j, k, err = 0, nr_contig_pages;
+ scif_pinned_pages_t pin;
+ phys_addr_t phys_prev, phys_curr;
+
+ might_sleep();
+
+ pin = window->pinned_pages;
+
+ if (intel_iommu_enabled && !scifdev_self(remote_dev))
+ return scif_iommu_map(remote_dev, window);
+
+ for (i = 0, j = 0; i < window->nr_pages; i += nr_contig_pages, j++) {
+ phys_prev = page_to_phys(pin->pages[i]);
+ nr_contig_pages = 1;
+
+ /* Detect physically contiguous chunks */
+ for (k = i + 1; k < window->nr_pages; k++) {
+ phys_curr = page_to_phys(pin->pages[k]);
+ if (phys_curr != (phys_prev + PAGE_SIZE))
+ break;
+ phys_prev = phys_curr;
+ nr_contig_pages++;
+ }
+ window->num_pages[j] = nr_contig_pages;
+ window->nr_contig_chunks++;
+ if (scif_is_mgmt_node()) {
+ /*
+ * Management node has to deal with SMPT on X100 and
+ * hence the DMA mapping is required
+ */
+ err = scif_map_single(&window->dma_addr[j],
+ phys_to_virt(page_to_phys(
+ pin->pages[i])),
+ remote_dev,
+ nr_contig_pages << PAGE_SHIFT);
+ if (err)
+ return err;
+ } else {
+ window->dma_addr[j] = page_to_phys(pin->pages[i]);
+ }
+ }
+ return err;
+}
+
+/**
+ * scif_send_scif_unregister:
+ * @ep: end point
+ * @window: self registration window
+ *
+ * Send a SCIF_UNREGISTER message.
+ */
+static int scif_send_scif_unregister(struct scif_endpt *ep,
+ struct scif_window *window)
+{
+ struct scifmsg msg;
+
+ msg.uop = SCIF_UNREGISTER;
+ msg.src = ep->port;
+ msg.payload[0] = window->alloc_handle.vaddr;
+ msg.payload[1] = (u64)window;
+ return scif_nodeqp_send(ep->remote_dev, &msg);
+}
+
+/**
+ * scif_unregister_window:
+ * @window: self registration window
+ *
+ * Send an unregistration request and wait for a response.
+ */
+int scif_unregister_window(struct scif_window *window)
+{
+ int err = 0;
+ struct scif_endpt *ep = (struct scif_endpt *)window->ep;
+ bool send_msg = false;
+
+ might_sleep();
+ switch (window->unreg_state) {
+ case OP_IDLE:
+ {
+ window->unreg_state = OP_IN_PROGRESS;
+ send_msg = true;
+ /* fall through */
+ }
+ case OP_IN_PROGRESS:
+ {
+ scif_get_window(window, 1);
+ mutex_unlock(&ep->rma_info.rma_lock);
+ if (send_msg) {
+ err = scif_send_scif_unregister(ep, window);
+ if (err) {
+ window->unreg_state = OP_COMPLETED;
+ goto done;
+ }
+ } else {
+ /* Return ENXIO since unregistration is in progress */
+ return -ENXIO;
+ }
+retry:
+ /* Wait for a SCIF_UNREGISTER_(N)ACK message */
+ err = wait_event_timeout(window->unregwq,
+ window->unreg_state != OP_IN_PROGRESS,
+ SCIF_NODE_ALIVE_TIMEOUT);
+ if (!err && scifdev_alive(ep))
+ goto retry;
+ if (!err) {
+ err = -ENODEV;
+ window->unreg_state = OP_COMPLETED;
+ dev_err(scif_info.mdev.this_device,
+ "%s %d err %d\n", __func__, __LINE__, err);
+ }
+ if (err > 0)
+ err = 0;
+done:
+ mutex_lock(&ep->rma_info.rma_lock);
+ scif_put_window(window, 1);
+ break;
+ }
+ case OP_FAILED:
+ {
+ if (!scifdev_alive(ep)) {
+ err = -ENODEV;
+ window->unreg_state = OP_COMPLETED;
+ }
+ break;
+ }
+ case OP_COMPLETED:
+ break;
+ default:
+ err = -ENODEV;
+ }
+
+ if (window->unreg_state == OP_COMPLETED && window->ref_count)
+ scif_put_window(window, window->nr_pages);
+
+ if (!window->ref_count) {
+ atomic_inc(&ep->rma_info.tw_refcount);
+ list_del_init(&window->list);
+ scif_free_window_offset(ep, window, window->offset);
+ mutex_unlock(&ep->rma_info.rma_lock);
+ if ((!!(window->pinned_pages->map_flags & SCIF_MAP_KERNEL)) &&
+ scifdev_alive(ep)) {
+ scif_drain_dma_intr(ep->remote_dev->sdev,
+ ep->rma_info.dma_chan);
+ } else {
+ if (!__scif_dec_pinned_vm_lock(window->mm,
+ window->nr_pages, 1)) {
+ __scif_release_mm(window->mm);
+ window->mm = NULL;
+ }
+ }
+ scif_queue_for_cleanup(window, &scif_info.rma);
+ mutex_lock(&ep->rma_info.rma_lock);
+ }
+ return err;
+}
+
+/**
+ * scif_send_alloc_request:
+ * @ep: end point
+ * @window: self registration window
+ *
+ * Send a remote window allocation request
+ */
+static int scif_send_alloc_request(struct scif_endpt *ep,
+ struct scif_window *window)
+{
+ struct scifmsg msg;
+ struct scif_allocmsg *alloc = &window->alloc_handle;
+
+ /* Set up the Alloc Handle */
+ alloc->state = OP_IN_PROGRESS;
+ init_waitqueue_head(&alloc->allocwq);
+
+ /* Send out an allocation request */
+ msg.uop = SCIF_ALLOC_REQ;
+ msg.payload[1] = window->nr_pages;
+ msg.payload[2] = (u64)&window->alloc_handle;
+ return _scif_nodeqp_send(ep->remote_dev, &msg);
+}
+
+/**
+ * scif_prep_remote_window:
+ * @ep: end point
+ * @window: self registration window
+ *
+ * Send a remote window allocation request, wait for an allocation response,
+ * and prepares the remote window by copying over the page lists
+ */
+static int scif_prep_remote_window(struct scif_endpt *ep,
+ struct scif_window *window)
+{
+ struct scifmsg msg;
+ struct scif_window *remote_window;
+ struct scif_allocmsg *alloc = &window->alloc_handle;
+ dma_addr_t *dma_phys_lookup, *tmp, *num_pages_lookup, *tmp1;
+ int i = 0, j = 0;
+ int nr_contig_chunks, loop_nr_contig_chunks;
+ int remaining_nr_contig_chunks, nr_lookup;
+ int err, map_err;
+
+ map_err = scif_map_window(ep->remote_dev, window);
+ if (map_err)
+ dev_err(&ep->remote_dev->sdev->dev,
+ "%s %d map_err %d\n", __func__, __LINE__, map_err);
+ remaining_nr_contig_chunks = window->nr_contig_chunks;
+ nr_contig_chunks = window->nr_contig_chunks;
+retry:
+ /* Wait for a SCIF_ALLOC_GNT/REJ message */
+ err = wait_event_timeout(alloc->allocwq,
+ alloc->state != OP_IN_PROGRESS,
+ SCIF_NODE_ALIVE_TIMEOUT);
+ mutex_lock(&ep->rma_info.rma_lock);
+ /* Synchronize with the thread waking up allocwq */
+ mutex_unlock(&ep->rma_info.rma_lock);
+ if (!err && scifdev_alive(ep))
+ goto retry;
+
+ if (!err)
+ err = -ENODEV;
+
+ if (err > 0)
+ err = 0;
+ else
+ return err;
+
+ /* Bail out. The remote end rejected this request */
+ if (alloc->state == OP_FAILED)
+ return -ENOMEM;
+
+ if (map_err) {
+ dev_err(&ep->remote_dev->sdev->dev,
+ "%s %d err %d\n", __func__, __LINE__, map_err);
+ msg.uop = SCIF_FREE_VIRT;
+ msg.src = ep->port;
+ msg.payload[0] = ep->remote_ep;
+ msg.payload[1] = window->alloc_handle.vaddr;
+ msg.payload[2] = (u64)window;
+ msg.payload[3] = SCIF_REGISTER;
+ spin_lock(&ep->lock);
+ if (ep->state == SCIFEP_CONNECTED)
+ err = _scif_nodeqp_send(ep->remote_dev, &msg);
+ else
+ err = -ENOTCONN;
+ spin_unlock(&ep->lock);
+ return err;
+ }
+
+ remote_window = scif_ioremap(alloc->phys_addr, sizeof(*window),
+ ep->remote_dev);
+
+ /* Compute the number of lookup entries. 21 == 2MB Shift */
+ nr_lookup = ALIGN(nr_contig_chunks, SCIF_NR_ADDR_IN_PAGE)
+ >> ilog2(SCIF_NR_ADDR_IN_PAGE);
+
+ dma_phys_lookup =
+ scif_ioremap(remote_window->dma_addr_lookup.offset,
+ nr_lookup *
+ sizeof(*remote_window->dma_addr_lookup.lookup),
+ ep->remote_dev);
+ num_pages_lookup =
+ scif_ioremap(remote_window->num_pages_lookup.offset,
+ nr_lookup *
+ sizeof(*remote_window->num_pages_lookup.lookup),
+ ep->remote_dev);
+
+ while (remaining_nr_contig_chunks) {
+ loop_nr_contig_chunks = min_t(int, remaining_nr_contig_chunks,
+ (int)SCIF_NR_ADDR_IN_PAGE);
+ /* #1/2 - Copy physical addresses over to the remote side */
+
+ /* #2/2 - Copy DMA addresses (addresses that are fed into the
+ * DMA engine) We transfer bus addresses which are then
+ * converted into a MIC physical address on the remote
+ * side if it is a MIC, if the remote node is a mgmt node we
+ * transfer the MIC physical address
+ */
+ tmp = scif_ioremap(dma_phys_lookup[j],
+ loop_nr_contig_chunks *
+ sizeof(*window->dma_addr),
+ ep->remote_dev);
+ tmp1 = scif_ioremap(num_pages_lookup[j],
+ loop_nr_contig_chunks *
+ sizeof(*window->num_pages),
+ ep->remote_dev);
+ if (scif_is_mgmt_node()) {
+ memcpy_toio((void __force __iomem *)tmp,
+ &window->dma_addr[i], loop_nr_contig_chunks
+ * sizeof(*window->dma_addr));
+ memcpy_toio((void __force __iomem *)tmp1,
+ &window->num_pages[i], loop_nr_contig_chunks
+ * sizeof(*window->num_pages));
+ } else {
+ if (scifdev_is_p2p(ep->remote_dev)) {
+ /*
+ * add remote node's base address for this node
+ * to convert it into a MIC address
+ */
+ int m;
+ dma_addr_t dma_addr;
+
+ for (m = 0; m < loop_nr_contig_chunks; m++) {
+ dma_addr = window->dma_addr[i + m] +
+ ep->remote_dev->base_addr;
+ writeq(dma_addr,
+ (void __force __iomem *)&tmp[m]);
+ }
+ memcpy_toio((void __force __iomem *)tmp1,
+ &window->num_pages[i],
+ loop_nr_contig_chunks
+ * sizeof(*window->num_pages));
+ } else {
+ /* Mgmt node or loopback - transfer DMA
+ * addresses as is, this is the same as a
+ * MIC physical address (we use the dma_addr
+ * and not the phys_addr array since the
+ * phys_addr is only setup if there is a mmap()
+ * request from the mgmt node)
+ */
+ memcpy_toio((void __force __iomem *)tmp,
+ &window->dma_addr[i],
+ loop_nr_contig_chunks *
+ sizeof(*window->dma_addr));
+ memcpy_toio((void __force __iomem *)tmp1,
+ &window->num_pages[i],
+ loop_nr_contig_chunks *
+ sizeof(*window->num_pages));
+ }
+ }
+ remaining_nr_contig_chunks -= loop_nr_contig_chunks;
+ i += loop_nr_contig_chunks;
+ j++;
+ scif_iounmap(tmp, loop_nr_contig_chunks *
+ sizeof(*window->dma_addr), ep->remote_dev);
+ scif_iounmap(tmp1, loop_nr_contig_chunks *
+ sizeof(*window->num_pages), ep->remote_dev);
+ }
+
+ /* Prepare the remote window for the peer */
+ remote_window->peer_window = (u64)window;
+ remote_window->offset = window->offset;
+ remote_window->prot = window->prot;
+ remote_window->nr_contig_chunks = nr_contig_chunks;
+ remote_window->ep = ep->remote_ep;
+ scif_iounmap(num_pages_lookup,
+ nr_lookup *
+ sizeof(*remote_window->num_pages_lookup.lookup),
+ ep->remote_dev);
+ scif_iounmap(dma_phys_lookup,
+ nr_lookup *
+ sizeof(*remote_window->dma_addr_lookup.lookup),
+ ep->remote_dev);
+ scif_iounmap(remote_window, sizeof(*remote_window), ep->remote_dev);
+ window->peer_window = alloc->vaddr;
+ return err;
+}
+
+/**
+ * scif_send_scif_register:
+ * @ep: end point
+ * @window: self registration window
+ *
+ * Send a SCIF_REGISTER message if EP is connected and wait for a
+ * SCIF_REGISTER_(N)ACK message else send a SCIF_FREE_VIRT
+ * message so that the peer can free its remote window allocated earlier.
+ */
+static int scif_send_scif_register(struct scif_endpt *ep,
+ struct scif_window *window)
+{
+ int err = 0;
+ struct scifmsg msg;
+
+ msg.src = ep->port;
+ msg.payload[0] = ep->remote_ep;
+ msg.payload[1] = window->alloc_handle.vaddr;
+ msg.payload[2] = (u64)window;
+ spin_lock(&ep->lock);
+ if (ep->state == SCIFEP_CONNECTED) {
+ msg.uop = SCIF_REGISTER;
+ window->reg_state = OP_IN_PROGRESS;
+ err = _scif_nodeqp_send(ep->remote_dev, &msg);
+ spin_unlock(&ep->lock);
+ if (!err) {
+retry:
+ /* Wait for a SCIF_REGISTER_(N)ACK message */
+ err = wait_event_timeout(window->regwq,
+ window->reg_state !=
+ OP_IN_PROGRESS,
+ SCIF_NODE_ALIVE_TIMEOUT);
+ if (!err && scifdev_alive(ep))
+ goto retry;
+ err = !err ? -ENODEV : 0;
+ if (window->reg_state == OP_FAILED)
+ err = -ENOTCONN;
+ }
+ } else {
+ msg.uop = SCIF_FREE_VIRT;
+ msg.payload[3] = SCIF_REGISTER;
+ err = _scif_nodeqp_send(ep->remote_dev, &msg);
+ spin_unlock(&ep->lock);
+ if (!err)
+ err = -ENOTCONN;
+ }
+ return err;
+}
+
+/**
+ * scif_get_window_offset:
+ * @ep: end point descriptor
+ * @flags: flags
+ * @offset: offset hint
+ * @num_pages: number of pages
+ * @out_offset: computed offset returned by reference.
+ *
+ * Compute/Claim a new offset for this EP.
+ */
+int scif_get_window_offset(struct scif_endpt *ep, int flags, s64 offset,
+ int num_pages, s64 *out_offset)
+{
+ s64 page_index;
+ struct iova *iova_ptr;
+ int err = 0;
+
+ if (flags & SCIF_MAP_FIXED) {
+ page_index = SCIF_IOVA_PFN(offset);
+ iova_ptr = reserve_iova(&ep->rma_info.iovad, page_index,
+ page_index + num_pages - 1);
+ if (!iova_ptr)
+ err = -EADDRINUSE;
+ } else {
+ iova_ptr = alloc_iova(&ep->rma_info.iovad, num_pages,
+ SCIF_DMA_63BIT_PFN - 1, 0);
+ if (!iova_ptr)
+ err = -ENOMEM;
+ }
+ if (!err)
+ *out_offset = (iova_ptr->pfn_lo) << PAGE_SHIFT;
+ return err;
+}
+
+/**
+ * scif_free_window_offset:
+ * @ep: end point descriptor
+ * @window: registration window
+ * @offset: Offset to be freed
+ *
+ * Free offset for this EP. The callee is supposed to grab
+ * the RMA mutex before calling this API.
+ */
+void scif_free_window_offset(struct scif_endpt *ep,
+ struct scif_window *window, s64 offset)
+{
+ if ((window && !window->offset_freed) || !window) {
+ free_iova(&ep->rma_info.iovad, offset >> PAGE_SHIFT);
+ if (window)
+ window->offset_freed = true;
+ }
+}
+
+/**
+ * scif_alloc_req: Respond to SCIF_ALLOC_REQ interrupt message
+ * @msg: Interrupt message
+ *
+ * Remote side is requesting a memory allocation.
+ */
+void scif_alloc_req(struct scif_dev *scifdev, struct scifmsg *msg)
+{
+ int err;
+ struct scif_window *window = NULL;
+ int nr_pages = msg->payload[1];
+
+ window = scif_create_remote_window(scifdev, nr_pages);
+ if (!window) {
+ err = -ENOMEM;
+ goto error;
+ }
+
+ /* The peer's allocation request is granted */
+ msg->uop = SCIF_ALLOC_GNT;
+ msg->payload[0] = (u64)window;
+ msg->payload[1] = window->mapped_offset;
+ err = scif_nodeqp_send(scifdev, msg);
+ if (err)
+ scif_destroy_remote_window(window);
+ return;
+error:
+ /* The peer's allocation request is rejected */
+ dev_err(&scifdev->sdev->dev,
+ "%s %d error %d alloc_ptr %p nr_pages 0x%x\n",
+ __func__, __LINE__, err, window, nr_pages);
+ msg->uop = SCIF_ALLOC_REJ;
+ scif_nodeqp_send(scifdev, msg);
+}
+
+/**
+ * scif_alloc_gnt_rej: Respond to SCIF_ALLOC_GNT/REJ interrupt message
+ * @msg: Interrupt message
+ *
+ * Remote side responded to a memory allocation.
+ */
+void scif_alloc_gnt_rej(struct scif_dev *scifdev, struct scifmsg *msg)
+{
+ struct scif_allocmsg *handle = (struct scif_allocmsg *)msg->payload[2];
+ struct scif_window *window = container_of(handle, struct scif_window,
+ alloc_handle);
+ struct scif_endpt *ep = (struct scif_endpt *)window->ep;
+
+ mutex_lock(&ep->rma_info.rma_lock);
+ handle->vaddr = msg->payload[0];
+ handle->phys_addr = msg->payload[1];
+ if (msg->uop == SCIF_ALLOC_GNT)
+ handle->state = OP_COMPLETED;
+ else
+ handle->state = OP_FAILED;
+ wake_up(&handle->allocwq);
+ mutex_unlock(&ep->rma_info.rma_lock);
+}
+
+/**
+ * scif_free_virt: Respond to SCIF_FREE_VIRT interrupt message
+ * @msg: Interrupt message
+ *
+ * Free up memory kmalloc'd earlier.
+ */
+void scif_free_virt(struct scif_dev *scifdev, struct scifmsg *msg)
+{
+ struct scif_window *window = (struct scif_window *)msg->payload[1];
+
+ scif_destroy_remote_window(window);
+}
+
+static void
+scif_fixup_aper_base(struct scif_dev *dev, struct scif_window *window)
+{
+ int j;
+ struct scif_hw_dev *sdev = dev->sdev;
+ phys_addr_t apt_base = 0;
+
+ /*
+ * Add the aperture base if the DMA address is not card relative
+ * since the DMA addresses need to be an offset into the bar
+ */
+ if (!scifdev_self(dev) && window->type == SCIF_WINDOW_PEER &&
+ sdev->aper && !sdev->card_rel_da)
+ apt_base = sdev->aper->pa;
+ else
+ return;
+
+ for (j = 0; j < window->nr_contig_chunks; j++) {
+ if (window->num_pages[j])
+ window->dma_addr[j] += apt_base;
+ else
+ break;
+ }
+}
+
+/**
+ * scif_recv_reg: Respond to SCIF_REGISTER interrupt message
+ * @msg: Interrupt message
+ *
+ * Update remote window list with a new registered window.
+ */
+void scif_recv_reg(struct scif_dev *scifdev, struct scifmsg *msg)
+{
+ struct scif_endpt *ep = (struct scif_endpt *)msg->payload[0];
+ struct scif_window *window =
+ (struct scif_window *)msg->payload[1];
+
+ mutex_lock(&ep->rma_info.rma_lock);
+ spin_lock(&ep->lock);
+ if (ep->state == SCIFEP_CONNECTED) {
+ msg->uop = SCIF_REGISTER_ACK;
+ scif_nodeqp_send(ep->remote_dev, msg);
+ scif_fixup_aper_base(ep->remote_dev, window);
+ /* No further failures expected. Insert new window */
+ scif_insert_window(window, &ep->rma_info.remote_reg_list);
+ } else {
+ msg->uop = SCIF_REGISTER_NACK;
+ scif_nodeqp_send(ep->remote_dev, msg);
+ }
+ spin_unlock(&ep->lock);
+ mutex_unlock(&ep->rma_info.rma_lock);
+ /* free up any lookup resources now that page lists are transferred */
+ scif_destroy_remote_lookup(ep->remote_dev, window);
+ /*
+ * We could not insert the window but we need to
+ * destroy the window.
+ */
+ if (msg->uop == SCIF_REGISTER_NACK)
+ scif_destroy_remote_window(window);
+}
+
+/**
+ * scif_recv_unreg: Respond to SCIF_UNREGISTER interrupt message
+ * @msg: Interrupt message
+ *
+ * Remove window from remote registration list;
+ */
+void scif_recv_unreg(struct scif_dev *scifdev, struct scifmsg *msg)
+{
+ struct scif_rma_req req;
+ struct scif_window *window = NULL;
+ struct scif_window *recv_window =
+ (struct scif_window *)msg->payload[0];
+ struct scif_endpt *ep;
+ int del_window = 0;
+
+ ep = (struct scif_endpt *)recv_window->ep;
+ req.out_window = &window;
+ req.offset = recv_window->offset;
+ req.prot = 0;
+ req.nr_bytes = recv_window->nr_pages << PAGE_SHIFT;
+ req.type = SCIF_WINDOW_FULL;
+ req.head = &ep->rma_info.remote_reg_list;
+ msg->payload[0] = ep->remote_ep;
+
+ mutex_lock(&ep->rma_info.rma_lock);
+ /* Does a valid window exist? */
+ if (scif_query_window(&req)) {
+ dev_err(&scifdev->sdev->dev,
+ "%s %d -ENXIO\n", __func__, __LINE__);
+ msg->uop = SCIF_UNREGISTER_ACK;
+ goto error;
+ }
+ if (window) {
+ if (window->ref_count)
+ scif_put_window(window, window->nr_pages);
+ else
+ dev_err(&scifdev->sdev->dev,
+ "%s %d ref count should be +ve\n",
+ __func__, __LINE__);
+ window->unreg_state = OP_COMPLETED;
+ if (!window->ref_count) {
+ msg->uop = SCIF_UNREGISTER_ACK;
+ atomic_inc(&ep->rma_info.tw_refcount);
+ ep->rma_info.async_list_del = 1;
+ list_del_init(&window->list);
+ del_window = 1;
+ } else {
+ /* NACK! There are valid references to this window */
+ msg->uop = SCIF_UNREGISTER_NACK;
+ }
+ } else {
+ /* The window did not make its way to the list at all. ACK */
+ msg->uop = SCIF_UNREGISTER_ACK;
+ scif_destroy_remote_window(recv_window);
+ }
+error:
+ mutex_unlock(&ep->rma_info.rma_lock);
+ if (del_window)
+ scif_drain_dma_intr(ep->remote_dev->sdev,
+ ep->rma_info.dma_chan);
+ scif_nodeqp_send(ep->remote_dev, msg);
+ if (del_window)
+ scif_queue_for_cleanup(window, &scif_info.rma);
+}
+
+/**
+ * scif_recv_reg_ack: Respond to SCIF_REGISTER_ACK interrupt message
+ * @msg: Interrupt message
+ *
+ * Wake up the window waiting to complete registration.
+ */
+void scif_recv_reg_ack(struct scif_dev *scifdev, struct scifmsg *msg)
+{
+ struct scif_window *window =
+ (struct scif_window *)msg->payload[2];
+ struct scif_endpt *ep = (struct scif_endpt *)window->ep;
+
+ mutex_lock(&ep->rma_info.rma_lock);
+ window->reg_state = OP_COMPLETED;
+ wake_up(&window->regwq);
+ mutex_unlock(&ep->rma_info.rma_lock);
+}
+
+/**
+ * scif_recv_reg_nack: Respond to SCIF_REGISTER_NACK interrupt message
+ * @msg: Interrupt message
+ *
+ * Wake up the window waiting to inform it that registration
+ * cannot be completed.
+ */
+void scif_recv_reg_nack(struct scif_dev *scifdev, struct scifmsg *msg)
+{
+ struct scif_window *window =
+ (struct scif_window *)msg->payload[2];
+ struct scif_endpt *ep = (struct scif_endpt *)window->ep;
+
+ mutex_lock(&ep->rma_info.rma_lock);
+ window->reg_state = OP_FAILED;
+ wake_up(&window->regwq);
+ mutex_unlock(&ep->rma_info.rma_lock);
+}
+
+/**
+ * scif_recv_unreg_ack: Respond to SCIF_UNREGISTER_ACK interrupt message
+ * @msg: Interrupt message
+ *
+ * Wake up the window waiting to complete unregistration.
+ */
+void scif_recv_unreg_ack(struct scif_dev *scifdev, struct scifmsg *msg)
+{
+ struct scif_window *window =
+ (struct scif_window *)msg->payload[1];
+ struct scif_endpt *ep = (struct scif_endpt *)window->ep;
+
+ mutex_lock(&ep->rma_info.rma_lock);
+ window->unreg_state = OP_COMPLETED;
+ wake_up(&window->unregwq);
+ mutex_unlock(&ep->rma_info.rma_lock);
+}
+
+/**
+ * scif_recv_unreg_nack: Respond to SCIF_UNREGISTER_NACK interrupt message
+ * @msg: Interrupt message
+ *
+ * Wake up the window waiting to inform it that unregistration
+ * cannot be completed immediately.
+ */
+void scif_recv_unreg_nack(struct scif_dev *scifdev, struct scifmsg *msg)
+{
+ struct scif_window *window =
+ (struct scif_window *)msg->payload[1];
+ struct scif_endpt *ep = (struct scif_endpt *)window->ep;
+
+ mutex_lock(&ep->rma_info.rma_lock);
+ window->unreg_state = OP_FAILED;
+ wake_up(&window->unregwq);
+ mutex_unlock(&ep->rma_info.rma_lock);
+}
+
+int __scif_pin_pages(void *addr, size_t len, int *out_prot,
+ int map_flags, scif_pinned_pages_t *pages)
+{
+ struct scif_pinned_pages *pinned_pages;
+ int nr_pages, err = 0, i;
+ bool vmalloc_addr = false;
+ bool try_upgrade = false;
+ int prot = *out_prot;
+ int ulimit = 0;
+ struct mm_struct *mm = NULL;
+
+ /* Unsupported flags */
+ if (map_flags & ~(SCIF_MAP_KERNEL | SCIF_MAP_ULIMIT))
+ return -EINVAL;
+ ulimit = !!(map_flags & SCIF_MAP_ULIMIT);
+
+ /* Unsupported protection requested */
+ if (prot & ~(SCIF_PROT_READ | SCIF_PROT_WRITE))
+ return -EINVAL;
+
+ /* addr/len must be page aligned. len should be non zero */
+ if (!len ||
+ (ALIGN((u64)addr, PAGE_SIZE) != (u64)addr) ||
+ (ALIGN((u64)len, PAGE_SIZE) != (u64)len))
+ return -EINVAL;
+
+ might_sleep();
+
+ nr_pages = len >> PAGE_SHIFT;
+
+ /* Allocate a set of pinned pages */
+ pinned_pages = scif_create_pinned_pages(nr_pages, prot);
+ if (!pinned_pages)
+ return -ENOMEM;
+
+ if (map_flags & SCIF_MAP_KERNEL) {
+ if (is_vmalloc_addr(addr))
+ vmalloc_addr = true;
+
+ for (i = 0; i < nr_pages; i++) {
+ if (vmalloc_addr)
+ pinned_pages->pages[i] =
+ vmalloc_to_page(addr + (i * PAGE_SIZE));
+ else
+ pinned_pages->pages[i] =
+ virt_to_page(addr + (i * PAGE_SIZE));
+ }
+ pinned_pages->nr_pages = nr_pages;
+ pinned_pages->map_flags = SCIF_MAP_KERNEL;
+ } else {
+ /*
+ * SCIF supports registration caching. If a registration has
+ * been requested with read only permissions, then we try
+ * to pin the pages with RW permissions so that a subsequent
+ * transfer with RW permission can hit the cache instead of
+ * invalidating it. If the upgrade fails with RW then we
+ * revert back to R permission and retry
+ */
+ if (prot == SCIF_PROT_READ)
+ try_upgrade = true;
+ prot |= SCIF_PROT_WRITE;
+retry:
+ mm = current->mm;
+ down_write(&mm->mmap_sem);
+ if (ulimit) {
+ err = __scif_check_inc_pinned_vm(mm, nr_pages);
+ if (err) {
+ up_write(&mm->mmap_sem);
+ pinned_pages->nr_pages = 0;
+ goto error_unmap;
+ }
+ }
+
+ pinned_pages->nr_pages = get_user_pages(
+ current,
+ mm,
+ (u64)addr,
+ nr_pages,
+ !!(prot & SCIF_PROT_WRITE),
+ 0,
+ pinned_pages->pages,
+ NULL);
+ up_write(&mm->mmap_sem);
+ if (nr_pages != pinned_pages->nr_pages) {
+ if (try_upgrade) {
+ if (ulimit)
+ __scif_dec_pinned_vm_lock(mm,
+ nr_pages, 0);
+ /* Roll back any pinned pages */
+ for (i = 0; i < pinned_pages->nr_pages; i++) {
+ if (pinned_pages->pages[i])
+ put_page(
+ pinned_pages->pages[i]);
+ }
+ prot &= ~SCIF_PROT_WRITE;
+ try_upgrade = false;
+ goto retry;
+ }
+ }
+ pinned_pages->map_flags = 0;
+ }
+
+ if (pinned_pages->nr_pages < nr_pages) {
+ err = -EFAULT;
+ pinned_pages->nr_pages = nr_pages;
+ goto dec_pinned;
+ }
+
+ *out_prot = prot;
+ atomic_set(&pinned_pages->ref_count, 1);
+ *pages = pinned_pages;
+ return err;
+dec_pinned:
+ if (ulimit)
+ __scif_dec_pinned_vm_lock(mm, nr_pages, 0);
+ /* Something went wrong! Rollback */
+error_unmap:
+ pinned_pages->nr_pages = nr_pages;
+ scif_destroy_pinned_pages(pinned_pages);
+ *pages = NULL;
+ dev_dbg(scif_info.mdev.this_device,
+ "%s %d err %d len 0x%lx\n", __func__, __LINE__, err, len);
+ return err;
+}
+
+int scif_pin_pages(void *addr, size_t len, int prot,
+ int map_flags, scif_pinned_pages_t *pages)
+{
+ return __scif_pin_pages(addr, len, &prot, map_flags, pages);
+}
+EXPORT_SYMBOL_GPL(scif_pin_pages);
+
+int scif_unpin_pages(scif_pinned_pages_t pinned_pages)
+{
+ int err = 0, ret;
+
+ if (!pinned_pages || SCIFEP_MAGIC != pinned_pages->magic)
+ return -EINVAL;
+
+ ret = atomic_sub_return(1, &pinned_pages->ref_count);
+ if (ret < 0) {
+ dev_err(scif_info.mdev.this_device,
+ "%s %d scif_unpin_pages called without pinning? rc %d\n",
+ __func__, __LINE__, ret);
+ return -EINVAL;
+ }
+ /*
+ * Destroy the window if the ref count for this set of pinned
+ * pages has dropped to zero. If it is positive then there is
+ * a valid registered window which is backed by these pages and
+ * it will be destroyed once all such windows are unregistered.
+ */
+ if (!ret)
+ err = scif_destroy_pinned_pages(pinned_pages);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(scif_unpin_pages);
+
+static inline void
+scif_insert_local_window(struct scif_window *window, struct scif_endpt *ep)
+{
+ mutex_lock(&ep->rma_info.rma_lock);
+ scif_insert_window(window, &ep->rma_info.reg_list);
+ mutex_unlock(&ep->rma_info.rma_lock);
+}
+
+off_t scif_register_pinned_pages(scif_epd_t epd,
+ scif_pinned_pages_t pinned_pages,
+ off_t offset, int map_flags)
+{
+ struct scif_endpt *ep = (struct scif_endpt *)epd;
+ s64 computed_offset;
+ struct scif_window *window;
+ int err;
+ size_t len;
+ struct device *spdev;
+
+ /* Unsupported flags */
+ if (map_flags & ~SCIF_MAP_FIXED)
+ return -EINVAL;
+
+ len = pinned_pages->nr_pages << PAGE_SHIFT;
+
+ /*
+ * Offset is not page aligned/negative or offset+len
+ * wraps around with SCIF_MAP_FIXED.
+ */
+ if ((map_flags & SCIF_MAP_FIXED) &&
+ ((ALIGN(offset, PAGE_SIZE) != offset) ||
+ (offset < 0) ||
+ (offset + (off_t)len < offset)))
+ return -EINVAL;
+
+ might_sleep();
+
+ err = scif_verify_epd(ep);
+ if (err)
+ return err;
+ /*
+ * It is an error to pass pinned_pages to scif_register_pinned_pages()
+ * after calling scif_unpin_pages().
+ */
+ if (!atomic_add_unless(&pinned_pages->ref_count, 1, 0))
+ return -EINVAL;
+
+ /* Compute the offset for this registration */
+ err = scif_get_window_offset(ep, map_flags, offset,
+ len, &computed_offset);
+ if (err) {
+ atomic_sub(1, &pinned_pages->ref_count);
+ return err;
+ }
+
+ /* Allocate and prepare self registration window */
+ window = scif_create_window(ep, pinned_pages->nr_pages,
+ computed_offset, false);
+ if (!window) {
+ atomic_sub(1, &pinned_pages->ref_count);
+ scif_free_window_offset(ep, NULL, computed_offset);
+ return -ENOMEM;
+ }
+
+ window->pinned_pages = pinned_pages;
+ window->nr_pages = pinned_pages->nr_pages;
+ window->prot = pinned_pages->prot;
+
+ spdev = scif_get_peer_dev(ep->remote_dev);
+ if (IS_ERR(spdev)) {
+ err = PTR_ERR(spdev);
+ scif_destroy_window(ep, window);
+ return err;
+ }
+ err = scif_send_alloc_request(ep, window);
+ if (err) {
+ dev_err(&ep->remote_dev->sdev->dev,
+ "%s %d err %d\n", __func__, __LINE__, err);
+ goto error_unmap;
+ }
+
+ /* Prepare the remote registration window */
+ err = scif_prep_remote_window(ep, window);
+ if (err) {
+ dev_err(&ep->remote_dev->sdev->dev,
+ "%s %d err %d\n", __func__, __LINE__, err);
+ goto error_unmap;
+ }
+
+ /* Tell the peer about the new window */
+ err = scif_send_scif_register(ep, window);
+ if (err) {
+ dev_err(&ep->remote_dev->sdev->dev,
+ "%s %d err %d\n", __func__, __LINE__, err);
+ goto error_unmap;
+ }
+
+ scif_put_peer_dev(spdev);
+ /* No further failures expected. Insert new window */
+ scif_insert_local_window(window, ep);
+ return computed_offset;
+error_unmap:
+ scif_destroy_window(ep, window);
+ scif_put_peer_dev(spdev);
+ dev_err(&ep->remote_dev->sdev->dev,
+ "%s %d err %d\n", __func__, __LINE__, err);
+ return err;
+}
+EXPORT_SYMBOL_GPL(scif_register_pinned_pages);
+
+off_t scif_register(scif_epd_t epd, void *addr, size_t len, off_t offset,
+ int prot, int map_flags)
+{
+ scif_pinned_pages_t pinned_pages;
+ off_t err;
+ struct scif_endpt *ep = (struct scif_endpt *)epd;
+ s64 computed_offset;
+ struct scif_window *window;
+ struct mm_struct *mm = NULL;
+ struct device *spdev;
+
+ dev_dbg(scif_info.mdev.this_device,
+ "SCIFAPI register: ep %p addr %p len 0x%lx offset 0x%lx prot 0x%x map_flags 0x%x\n",
+ epd, addr, len, offset, prot, map_flags);
+ /* Unsupported flags */
+ if (map_flags & ~(SCIF_MAP_FIXED | SCIF_MAP_KERNEL))
+ return -EINVAL;
+
+ /*
+ * Offset is not page aligned/negative or offset+len
+ * wraps around with SCIF_MAP_FIXED.
+ */
+ if ((map_flags & SCIF_MAP_FIXED) &&
+ ((ALIGN(offset, PAGE_SIZE) != offset) ||
+ (offset < 0) ||
+ (offset + (off_t)len < offset)))
+ return -EINVAL;
+
+ /* Unsupported protection requested */
+ if (prot & ~(SCIF_PROT_READ | SCIF_PROT_WRITE))
+ return -EINVAL;
+
+ /* addr/len must be page aligned. len should be non zero */
+ if (!len || (ALIGN((u64)addr, PAGE_SIZE) != (u64)addr) ||
+ (ALIGN(len, PAGE_SIZE) != len))
+ return -EINVAL;
+
+ might_sleep();
+
+ err = scif_verify_epd(ep);
+ if (err)
+ return err;
+
+ /* Compute the offset for this registration */
+ err = scif_get_window_offset(ep, map_flags, offset,
+ len >> PAGE_SHIFT, &computed_offset);
+ if (err)
+ return err;
+
+ spdev = scif_get_peer_dev(ep->remote_dev);
+ if (IS_ERR(spdev)) {
+ err = PTR_ERR(spdev);
+ scif_free_window_offset(ep, NULL, computed_offset);
+ return err;
+ }
+ /* Allocate and prepare self registration window */
+ window = scif_create_window(ep, len >> PAGE_SHIFT,
+ computed_offset, false);
+ if (!window) {
+ scif_free_window_offset(ep, NULL, computed_offset);
+ scif_put_peer_dev(spdev);
+ return -ENOMEM;
+ }
+
+ window->nr_pages = len >> PAGE_SHIFT;
+
+ err = scif_send_alloc_request(ep, window);
+ if (err) {
+ scif_destroy_incomplete_window(ep, window);
+ scif_put_peer_dev(spdev);
+ return err;
+ }
+
+ if (!(map_flags & SCIF_MAP_KERNEL)) {
+ mm = __scif_acquire_mm();
+ map_flags |= SCIF_MAP_ULIMIT;
+ }
+ /* Pin down the pages */
+ err = __scif_pin_pages(addr, len, &prot,
+ map_flags & (SCIF_MAP_KERNEL | SCIF_MAP_ULIMIT),
+ &pinned_pages);
+ if (err) {
+ scif_destroy_incomplete_window(ep, window);
+ __scif_release_mm(mm);
+ goto error;
+ }
+
+ window->pinned_pages = pinned_pages;
+ window->prot = pinned_pages->prot;
+ window->mm = mm;
+
+ /* Prepare the remote registration window */
+ err = scif_prep_remote_window(ep, window);
+ if (err) {
+ dev_err(&ep->remote_dev->sdev->dev,
+ "%s %d err %ld\n", __func__, __LINE__, err);
+ goto error_unmap;
+ }
+
+ /* Tell the peer about the new window */
+ err = scif_send_scif_register(ep, window);
+ if (err) {
+ dev_err(&ep->remote_dev->sdev->dev,
+ "%s %d err %ld\n", __func__, __LINE__, err);
+ goto error_unmap;
+ }
+
+ scif_put_peer_dev(spdev);
+ /* No further failures expected. Insert new window */
+ scif_insert_local_window(window, ep);
+ dev_dbg(&ep->remote_dev->sdev->dev,
+ "SCIFAPI register: ep %p addr %p len 0x%lx computed_offset 0x%llx\n",
+ epd, addr, len, computed_offset);
+ return computed_offset;
+error_unmap:
+ scif_destroy_window(ep, window);
+error:
+ scif_put_peer_dev(spdev);
+ dev_err(&ep->remote_dev->sdev->dev,
+ "%s %d err %ld\n", __func__, __LINE__, err);
+ return err;
+}
+EXPORT_SYMBOL_GPL(scif_register);
+
+int
+scif_unregister(scif_epd_t epd, off_t offset, size_t len)
+{
+ struct scif_endpt *ep = (struct scif_endpt *)epd;
+ struct scif_window *window = NULL;
+ struct scif_rma_req req;
+ int nr_pages, err;
+ struct device *spdev;
+
+ dev_dbg(scif_info.mdev.this_device,
+ "SCIFAPI unregister: ep %p offset 0x%lx len 0x%lx\n",
+ ep, offset, len);
+ /* len must be page aligned. len should be non zero */
+ if (!len ||
+ (ALIGN((u64)len, PAGE_SIZE) != (u64)len))
+ return -EINVAL;
+
+ /* Offset is not page aligned or offset+len wraps around */
+ if ((ALIGN(offset, PAGE_SIZE) != offset) ||
+ (offset + (off_t)len < offset))
+ return -EINVAL;
+
+ err = scif_verify_epd(ep);
+ if (err)
+ return err;
+
+ might_sleep();
+ nr_pages = len >> PAGE_SHIFT;
+
+ req.out_window = &window;
+ req.offset = offset;
+ req.prot = 0;
+ req.nr_bytes = len;
+ req.type = SCIF_WINDOW_FULL;
+ req.head = &ep->rma_info.reg_list;
+
+ spdev = scif_get_peer_dev(ep->remote_dev);
+ if (IS_ERR(spdev)) {
+ err = PTR_ERR(spdev);
+ return err;
+ }
+ mutex_lock(&ep->rma_info.rma_lock);
+ /* Does a valid window exist? */
+ err = scif_query_window(&req);
+ if (err) {
+ dev_err(&ep->remote_dev->sdev->dev,
+ "%s %d err %d\n", __func__, __LINE__, err);
+ goto error;
+ }
+ /* Unregister all the windows in this range */
+ err = scif_rma_list_unregister(window, offset, nr_pages);
+ if (err)
+ dev_err(&ep->remote_dev->sdev->dev,
+ "%s %d err %d\n", __func__, __LINE__, err);
+error:
+ mutex_unlock(&ep->rma_info.rma_lock);
+ scif_put_peer_dev(spdev);
+ return err;
+}
+EXPORT_SYMBOL_GPL(scif_unregister);