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path: root/drivers/misc/mic/scif/scif_dma.c
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Diffstat (limited to 'drivers/misc/mic/scif/scif_dma.c')
-rw-r--r--drivers/misc/mic/scif/scif_dma.c1979
1 files changed, 1979 insertions, 0 deletions
diff --git a/drivers/misc/mic/scif/scif_dma.c b/drivers/misc/mic/scif/scif_dma.c
new file mode 100644
index 000000000000..95a13c629a8e
--- /dev/null
+++ b/drivers/misc/mic/scif/scif_dma.c
@@ -0,0 +1,1979 @@
+/*
+ * 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 "scif_main.h"
+#include "scif_map.h"
+
+/*
+ * struct scif_dma_comp_cb - SCIF DMA completion callback
+ *
+ * @dma_completion_func: DMA completion callback
+ * @cb_cookie: DMA completion callback cookie
+ * @temp_buf: Temporary buffer
+ * @temp_buf_to_free: Temporary buffer to be freed
+ * @is_cache: Is a kmem_cache allocated buffer
+ * @dst_offset: Destination registration offset
+ * @dst_window: Destination registration window
+ * @len: Length of the temp buffer
+ * @temp_phys: DMA address of the temp buffer
+ * @sdev: The SCIF device
+ * @header_padding: padding for cache line alignment
+ */
+struct scif_dma_comp_cb {
+ void (*dma_completion_func)(void *cookie);
+ void *cb_cookie;
+ u8 *temp_buf;
+ u8 *temp_buf_to_free;
+ bool is_cache;
+ s64 dst_offset;
+ struct scif_window *dst_window;
+ size_t len;
+ dma_addr_t temp_phys;
+ struct scif_dev *sdev;
+ int header_padding;
+};
+
+/**
+ * struct scif_copy_work - Work for DMA copy
+ *
+ * @src_offset: Starting source offset
+ * @dst_offset: Starting destination offset
+ * @src_window: Starting src registered window
+ * @dst_window: Starting dst registered window
+ * @loopback: true if this is a loopback DMA transfer
+ * @len: Length of the transfer
+ * @comp_cb: DMA copy completion callback
+ * @remote_dev: The remote SCIF peer device
+ * @fence_type: polling or interrupt based
+ * @ordered: is this a tail byte ordered DMA transfer
+ */
+struct scif_copy_work {
+ s64 src_offset;
+ s64 dst_offset;
+ struct scif_window *src_window;
+ struct scif_window *dst_window;
+ int loopback;
+ size_t len;
+ struct scif_dma_comp_cb *comp_cb;
+ struct scif_dev *remote_dev;
+ int fence_type;
+ bool ordered;
+};
+
+#ifndef list_entry_next
+#define list_entry_next(pos, member) \
+ list_entry(pos->member.next, typeof(*pos), member)
+#endif
+
+/**
+ * scif_reserve_dma_chan:
+ * @ep: Endpoint Descriptor.
+ *
+ * This routine reserves a DMA channel for a particular
+ * endpoint. All DMA transfers for an endpoint are always
+ * programmed on the same DMA channel.
+ */
+int scif_reserve_dma_chan(struct scif_endpt *ep)
+{
+ int err = 0;
+ struct scif_dev *scifdev;
+ struct scif_hw_dev *sdev;
+ struct dma_chan *chan;
+
+ /* Loopback DMAs are not supported on the management node */
+ if (!scif_info.nodeid && scifdev_self(ep->remote_dev))
+ return 0;
+ if (scif_info.nodeid)
+ scifdev = &scif_dev[0];
+ else
+ scifdev = ep->remote_dev;
+ sdev = scifdev->sdev;
+ if (!sdev->num_dma_ch)
+ return -ENODEV;
+ chan = sdev->dma_ch[scifdev->dma_ch_idx];
+ scifdev->dma_ch_idx = (scifdev->dma_ch_idx + 1) % sdev->num_dma_ch;
+ mutex_lock(&ep->rma_info.rma_lock);
+ ep->rma_info.dma_chan = chan;
+ mutex_unlock(&ep->rma_info.rma_lock);
+ return err;
+}
+
+#ifdef CONFIG_MMU_NOTIFIER
+/**
+ * scif_rma_destroy_tcw:
+ *
+ * This routine destroys temporary cached windows
+ */
+static
+void __scif_rma_destroy_tcw(struct scif_mmu_notif *mmn,
+ struct scif_endpt *ep,
+ u64 start, u64 len)
+{
+ struct list_head *item, *tmp;
+ struct scif_window *window;
+ u64 start_va, end_va;
+ u64 end = start + len;
+
+ if (end <= start)
+ return;
+
+ list_for_each_safe(item, tmp, &mmn->tc_reg_list) {
+ window = list_entry(item, struct scif_window, list);
+ ep = (struct scif_endpt *)window->ep;
+ if (!len)
+ break;
+ start_va = window->va_for_temp;
+ end_va = start_va + (window->nr_pages << PAGE_SHIFT);
+ if (start < start_va && end <= start_va)
+ break;
+ if (start >= end_va)
+ continue;
+ __scif_rma_destroy_tcw_helper(window);
+ }
+}
+
+static void scif_rma_destroy_tcw(struct scif_mmu_notif *mmn, u64 start, u64 len)
+{
+ struct scif_endpt *ep = mmn->ep;
+
+ spin_lock(&ep->rma_info.tc_lock);
+ __scif_rma_destroy_tcw(mmn, ep, start, len);
+ spin_unlock(&ep->rma_info.tc_lock);
+}
+
+static void scif_rma_destroy_tcw_ep(struct scif_endpt *ep)
+{
+ struct list_head *item, *tmp;
+ struct scif_mmu_notif *mmn;
+
+ list_for_each_safe(item, tmp, &ep->rma_info.mmn_list) {
+ mmn = list_entry(item, struct scif_mmu_notif, list);
+ scif_rma_destroy_tcw(mmn, 0, ULONG_MAX);
+ }
+}
+
+static void __scif_rma_destroy_tcw_ep(struct scif_endpt *ep)
+{
+ struct list_head *item, *tmp;
+ struct scif_mmu_notif *mmn;
+
+ spin_lock(&ep->rma_info.tc_lock);
+ list_for_each_safe(item, tmp, &ep->rma_info.mmn_list) {
+ mmn = list_entry(item, struct scif_mmu_notif, list);
+ __scif_rma_destroy_tcw(mmn, ep, 0, ULONG_MAX);
+ }
+ spin_unlock(&ep->rma_info.tc_lock);
+}
+
+static bool scif_rma_tc_can_cache(struct scif_endpt *ep, size_t cur_bytes)
+{
+ if ((cur_bytes >> PAGE_SHIFT) > scif_info.rma_tc_limit)
+ return false;
+ if ((atomic_read(&ep->rma_info.tcw_total_pages)
+ + (cur_bytes >> PAGE_SHIFT)) >
+ scif_info.rma_tc_limit) {
+ dev_info(scif_info.mdev.this_device,
+ "%s %d total=%d, current=%zu reached max\n",
+ __func__, __LINE__,
+ atomic_read(&ep->rma_info.tcw_total_pages),
+ (1 + (cur_bytes >> PAGE_SHIFT)));
+ scif_rma_destroy_tcw_invalid();
+ __scif_rma_destroy_tcw_ep(ep);
+ }
+ return true;
+}
+
+static void scif_mmu_notifier_release(struct mmu_notifier *mn,
+ struct mm_struct *mm)
+{
+ struct scif_mmu_notif *mmn;
+
+ mmn = container_of(mn, struct scif_mmu_notif, ep_mmu_notifier);
+ scif_rma_destroy_tcw(mmn, 0, ULONG_MAX);
+ schedule_work(&scif_info.misc_work);
+}
+
+static void scif_mmu_notifier_invalidate_page(struct mmu_notifier *mn,
+ struct mm_struct *mm,
+ unsigned long address)
+{
+ struct scif_mmu_notif *mmn;
+
+ mmn = container_of(mn, struct scif_mmu_notif, ep_mmu_notifier);
+ scif_rma_destroy_tcw(mmn, address, PAGE_SIZE);
+}
+
+static void scif_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
+ struct mm_struct *mm,
+ unsigned long start,
+ unsigned long end)
+{
+ struct scif_mmu_notif *mmn;
+
+ mmn = container_of(mn, struct scif_mmu_notif, ep_mmu_notifier);
+ scif_rma_destroy_tcw(mmn, start, end - start);
+}
+
+static void scif_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
+ struct mm_struct *mm,
+ unsigned long start,
+ unsigned long end)
+{
+ /*
+ * Nothing to do here, everything needed was done in
+ * invalidate_range_start.
+ */
+}
+
+static const struct mmu_notifier_ops scif_mmu_notifier_ops = {
+ .release = scif_mmu_notifier_release,
+ .clear_flush_young = NULL,
+ .invalidate_page = scif_mmu_notifier_invalidate_page,
+ .invalidate_range_start = scif_mmu_notifier_invalidate_range_start,
+ .invalidate_range_end = scif_mmu_notifier_invalidate_range_end};
+
+static void scif_ep_unregister_mmu_notifier(struct scif_endpt *ep)
+{
+ struct scif_endpt_rma_info *rma = &ep->rma_info;
+ struct scif_mmu_notif *mmn = NULL;
+ struct list_head *item, *tmp;
+
+ mutex_lock(&ep->rma_info.mmn_lock);
+ list_for_each_safe(item, tmp, &rma->mmn_list) {
+ mmn = list_entry(item, struct scif_mmu_notif, list);
+ mmu_notifier_unregister(&mmn->ep_mmu_notifier, mmn->mm);
+ list_del(item);
+ kfree(mmn);
+ }
+ mutex_unlock(&ep->rma_info.mmn_lock);
+}
+
+static void scif_init_mmu_notifier(struct scif_mmu_notif *mmn,
+ struct mm_struct *mm, struct scif_endpt *ep)
+{
+ mmn->ep = ep;
+ mmn->mm = mm;
+ mmn->ep_mmu_notifier.ops = &scif_mmu_notifier_ops;
+ INIT_LIST_HEAD(&mmn->list);
+ INIT_LIST_HEAD(&mmn->tc_reg_list);
+}
+
+static struct scif_mmu_notif *
+scif_find_mmu_notifier(struct mm_struct *mm, struct scif_endpt_rma_info *rma)
+{
+ struct scif_mmu_notif *mmn;
+ struct list_head *item;
+
+ list_for_each(item, &rma->mmn_list) {
+ mmn = list_entry(item, struct scif_mmu_notif, list);
+ if (mmn->mm == mm)
+ return mmn;
+ }
+ return NULL;
+}
+
+static struct scif_mmu_notif *
+scif_add_mmu_notifier(struct mm_struct *mm, struct scif_endpt *ep)
+{
+ struct scif_mmu_notif *mmn
+ = kzalloc(sizeof(*mmn), GFP_KERNEL);
+
+ if (!mmn)
+ return ERR_PTR(ENOMEM);
+
+ scif_init_mmu_notifier(mmn, current->mm, ep);
+ if (mmu_notifier_register(&mmn->ep_mmu_notifier,
+ current->mm)) {
+ kfree(mmn);
+ return ERR_PTR(EBUSY);
+ }
+ list_add(&mmn->list, &ep->rma_info.mmn_list);
+ return mmn;
+}
+
+/*
+ * Called from the misc thread to destroy temporary cached windows and
+ * unregister the MMU notifier for the SCIF endpoint.
+ */
+void scif_mmu_notif_handler(struct work_struct *work)
+{
+ struct list_head *pos, *tmpq;
+ struct scif_endpt *ep;
+restart:
+ scif_rma_destroy_tcw_invalid();
+ spin_lock(&scif_info.rmalock);
+ list_for_each_safe(pos, tmpq, &scif_info.mmu_notif_cleanup) {
+ ep = list_entry(pos, struct scif_endpt, mmu_list);
+ list_del(&ep->mmu_list);
+ spin_unlock(&scif_info.rmalock);
+ scif_rma_destroy_tcw_ep(ep);
+ scif_ep_unregister_mmu_notifier(ep);
+ goto restart;
+ }
+ spin_unlock(&scif_info.rmalock);
+}
+
+static bool scif_is_set_reg_cache(int flags)
+{
+ return !!(flags & SCIF_RMA_USECACHE);
+}
+#else
+static struct scif_mmu_notif *
+scif_find_mmu_notifier(struct mm_struct *mm,
+ struct scif_endpt_rma_info *rma)
+{
+ return NULL;
+}
+
+static struct scif_mmu_notif *
+scif_add_mmu_notifier(struct mm_struct *mm, struct scif_endpt *ep)
+{
+ return NULL;
+}
+
+void scif_mmu_notif_handler(struct work_struct *work)
+{
+}
+
+static bool scif_is_set_reg_cache(int flags)
+{
+ return false;
+}
+
+static bool scif_rma_tc_can_cache(struct scif_endpt *ep, size_t cur_bytes)
+{
+ return false;
+}
+#endif
+
+/**
+ * scif_register_temp:
+ * @epd: End Point Descriptor.
+ * @addr: virtual address to/from which to copy
+ * @len: length of range to copy
+ * @out_offset: computed offset returned by reference.
+ * @out_window: allocated registered window returned by reference.
+ *
+ * Create a temporary registered window. The peer will not know about this
+ * window. This API is used for scif_vreadfrom()/scif_vwriteto() API's.
+ */
+static int
+scif_register_temp(scif_epd_t epd, unsigned long addr, size_t len, int prot,
+ off_t *out_offset, struct scif_window **out_window)
+{
+ struct scif_endpt *ep = (struct scif_endpt *)epd;
+ int err;
+ scif_pinned_pages_t pinned_pages;
+ size_t aligned_len;
+
+ aligned_len = ALIGN(len, PAGE_SIZE);
+
+ err = __scif_pin_pages((void *)(addr & PAGE_MASK),
+ aligned_len, &prot, 0, &pinned_pages);
+ if (err)
+ return err;
+
+ pinned_pages->prot = prot;
+
+ /* Compute the offset for this registration */
+ err = scif_get_window_offset(ep, 0, 0,
+ aligned_len >> PAGE_SHIFT,
+ (s64 *)out_offset);
+ if (err)
+ goto error_unpin;
+
+ /* Allocate and prepare self registration window */
+ *out_window = scif_create_window(ep, aligned_len >> PAGE_SHIFT,
+ *out_offset, true);
+ if (!*out_window) {
+ scif_free_window_offset(ep, NULL, *out_offset);
+ err = -ENOMEM;
+ goto error_unpin;
+ }
+
+ (*out_window)->pinned_pages = pinned_pages;
+ (*out_window)->nr_pages = pinned_pages->nr_pages;
+ (*out_window)->prot = pinned_pages->prot;
+
+ (*out_window)->va_for_temp = addr & PAGE_MASK;
+ err = scif_map_window(ep->remote_dev, *out_window);
+ if (err) {
+ /* Something went wrong! Rollback */
+ scif_destroy_window(ep, *out_window);
+ *out_window = NULL;
+ } else {
+ *out_offset |= (addr - (*out_window)->va_for_temp);
+ }
+ return err;
+error_unpin:
+ if (err)
+ dev_err(&ep->remote_dev->sdev->dev,
+ "%s %d err %d\n", __func__, __LINE__, err);
+ scif_unpin_pages(pinned_pages);
+ return err;
+}
+
+#define SCIF_DMA_TO (3 * HZ)
+
+/*
+ * scif_sync_dma - Program a DMA without an interrupt descriptor
+ *
+ * @dev - The address of the pointer to the device instance used
+ * for DMA registration.
+ * @chan - DMA channel to be used.
+ * @sync_wait: Wait for DMA to complete?
+ *
+ * Return 0 on success and -errno on error.
+ */
+static int scif_sync_dma(struct scif_hw_dev *sdev, struct dma_chan *chan,
+ bool sync_wait)
+{
+ int err = 0;
+ struct dma_async_tx_descriptor *tx = NULL;
+ enum dma_ctrl_flags flags = DMA_PREP_FENCE;
+ dma_cookie_t cookie;
+ struct dma_device *ddev;
+
+ if (!chan) {
+ err = -EIO;
+ dev_err(&sdev->dev, "%s %d err %d\n",
+ __func__, __LINE__, err);
+ return err;
+ }
+ ddev = chan->device;
+
+ tx = ddev->device_prep_dma_memcpy(chan, 0, 0, 0, flags);
+ if (!tx) {
+ err = -ENOMEM;
+ dev_err(&sdev->dev, "%s %d err %d\n",
+ __func__, __LINE__, err);
+ goto release;
+ }
+ cookie = tx->tx_submit(tx);
+
+ if (dma_submit_error(cookie)) {
+ err = -ENOMEM;
+ dev_err(&sdev->dev, "%s %d err %d\n",
+ __func__, __LINE__, err);
+ goto release;
+ }
+ if (!sync_wait) {
+ dma_async_issue_pending(chan);
+ } else {
+ if (dma_sync_wait(chan, cookie) == DMA_COMPLETE) {
+ err = 0;
+ } else {
+ err = -EIO;
+ dev_err(&sdev->dev, "%s %d err %d\n",
+ __func__, __LINE__, err);
+ }
+ }
+release:
+ return err;
+}
+
+static void scif_dma_callback(void *arg)
+{
+ struct completion *done = (struct completion *)arg;
+
+ complete(done);
+}
+
+#define SCIF_DMA_SYNC_WAIT true
+#define SCIF_DMA_POLL BIT(0)
+#define SCIF_DMA_INTR BIT(1)
+
+/*
+ * scif_async_dma - Program a DMA with an interrupt descriptor
+ *
+ * @dev - The address of the pointer to the device instance used
+ * for DMA registration.
+ * @chan - DMA channel to be used.
+ * Return 0 on success and -errno on error.
+ */
+static int scif_async_dma(struct scif_hw_dev *sdev, struct dma_chan *chan)
+{
+ int err = 0;
+ struct dma_device *ddev;
+ struct dma_async_tx_descriptor *tx = NULL;
+ enum dma_ctrl_flags flags = DMA_PREP_INTERRUPT | DMA_PREP_FENCE;
+ DECLARE_COMPLETION_ONSTACK(done_wait);
+ dma_cookie_t cookie;
+ enum dma_status status;
+
+ if (!chan) {
+ err = -EIO;
+ dev_err(&sdev->dev, "%s %d err %d\n",
+ __func__, __LINE__, err);
+ return err;
+ }
+ ddev = chan->device;
+
+ tx = ddev->device_prep_dma_memcpy(chan, 0, 0, 0, flags);
+ if (!tx) {
+ err = -ENOMEM;
+ dev_err(&sdev->dev, "%s %d err %d\n",
+ __func__, __LINE__, err);
+ goto release;
+ }
+ reinit_completion(&done_wait);
+ tx->callback = scif_dma_callback;
+ tx->callback_param = &done_wait;
+ cookie = tx->tx_submit(tx);
+
+ if (dma_submit_error(cookie)) {
+ err = -ENOMEM;
+ dev_err(&sdev->dev, "%s %d err %d\n",
+ __func__, __LINE__, err);
+ goto release;
+ }
+ dma_async_issue_pending(chan);
+
+ err = wait_for_completion_timeout(&done_wait, SCIF_DMA_TO);
+ if (!err) {
+ err = -EIO;
+ dev_err(&sdev->dev, "%s %d err %d\n",
+ __func__, __LINE__, err);
+ goto release;
+ }
+ err = 0;
+ status = dma_async_is_tx_complete(chan, cookie, NULL, NULL);
+ if (status != DMA_COMPLETE) {
+ err = -EIO;
+ dev_err(&sdev->dev, "%s %d err %d\n",
+ __func__, __LINE__, err);
+ goto release;
+ }
+release:
+ return err;
+}
+
+/*
+ * scif_drain_dma_poll - Drain all outstanding DMA operations for a particular
+ * DMA channel via polling.
+ *
+ * @sdev - The SCIF device
+ * @chan - DMA channel
+ * Return 0 on success and -errno on error.
+ */
+static int scif_drain_dma_poll(struct scif_hw_dev *sdev, struct dma_chan *chan)
+{
+ if (!chan)
+ return -EINVAL;
+ return scif_sync_dma(sdev, chan, SCIF_DMA_SYNC_WAIT);
+}
+
+/*
+ * scif_drain_dma_intr - Drain all outstanding DMA operations for a particular
+ * DMA channel via interrupt based blocking wait.
+ *
+ * @sdev - The SCIF device
+ * @chan - DMA channel
+ * Return 0 on success and -errno on error.
+ */
+int scif_drain_dma_intr(struct scif_hw_dev *sdev, struct dma_chan *chan)
+{
+ if (!chan)
+ return -EINVAL;
+ return scif_async_dma(sdev, chan);
+}
+
+/**
+ * scif_rma_destroy_windows:
+ *
+ * This routine destroys all windows queued for cleanup
+ */
+void scif_rma_destroy_windows(void)
+{
+ struct list_head *item, *tmp;
+ struct scif_window *window;
+ struct scif_endpt *ep;
+ struct dma_chan *chan;
+
+ might_sleep();
+restart:
+ spin_lock(&scif_info.rmalock);
+ list_for_each_safe(item, tmp, &scif_info.rma) {
+ window = list_entry(item, struct scif_window,
+ list);
+ ep = (struct scif_endpt *)window->ep;
+ chan = ep->rma_info.dma_chan;
+
+ list_del_init(&window->list);
+ spin_unlock(&scif_info.rmalock);
+ if (!chan || !scifdev_alive(ep) ||
+ !scif_drain_dma_intr(ep->remote_dev->sdev,
+ ep->rma_info.dma_chan))
+ /* Remove window from global list */
+ window->unreg_state = OP_COMPLETED;
+ else
+ dev_warn(&ep->remote_dev->sdev->dev,
+ "DMA engine hung?\n");
+ if (window->unreg_state == OP_COMPLETED) {
+ if (window->type == SCIF_WINDOW_SELF)
+ scif_destroy_window(ep, window);
+ else
+ scif_destroy_remote_window(window);
+ atomic_dec(&ep->rma_info.tw_refcount);
+ }
+ goto restart;
+ }
+ spin_unlock(&scif_info.rmalock);
+}
+
+/**
+ * scif_rma_destroy_tcw:
+ *
+ * This routine destroys temporary cached registered windows
+ * which have been queued for cleanup.
+ */
+void scif_rma_destroy_tcw_invalid(void)
+{
+ struct list_head *item, *tmp;
+ struct scif_window *window;
+ struct scif_endpt *ep;
+ struct dma_chan *chan;
+
+ might_sleep();
+restart:
+ spin_lock(&scif_info.rmalock);
+ list_for_each_safe(item, tmp, &scif_info.rma_tc) {
+ window = list_entry(item, struct scif_window, list);
+ ep = (struct scif_endpt *)window->ep;
+ chan = ep->rma_info.dma_chan;
+ list_del_init(&window->list);
+ spin_unlock(&scif_info.rmalock);
+ mutex_lock(&ep->rma_info.rma_lock);
+ if (!chan || !scifdev_alive(ep) ||
+ !scif_drain_dma_intr(ep->remote_dev->sdev,
+ ep->rma_info.dma_chan)) {
+ atomic_sub(window->nr_pages,
+ &ep->rma_info.tcw_total_pages);
+ scif_destroy_window(ep, window);
+ atomic_dec(&ep->rma_info.tcw_refcount);
+ } else {
+ dev_warn(&ep->remote_dev->sdev->dev,
+ "DMA engine hung?\n");
+ }
+ mutex_unlock(&ep->rma_info.rma_lock);
+ goto restart;
+ }
+ spin_unlock(&scif_info.rmalock);
+}
+
+static inline
+void *_get_local_va(off_t off, struct scif_window *window, size_t len)
+{
+ int page_nr = (off - window->offset) >> PAGE_SHIFT;
+ off_t page_off = off & ~PAGE_MASK;
+ void *va = NULL;
+
+ if (window->type == SCIF_WINDOW_SELF) {
+ struct page **pages = window->pinned_pages->pages;
+
+ va = page_address(pages[page_nr]) + page_off;
+ }
+ return va;
+}
+
+static inline
+void *ioremap_remote(off_t off, struct scif_window *window,
+ size_t len, struct scif_dev *dev,
+ struct scif_window_iter *iter)
+{
+ dma_addr_t phys = scif_off_to_dma_addr(window, off, NULL, iter);
+
+ /*
+ * If the DMA address is not card relative then we need the DMA
+ * addresses to be an offset into the bar. The aperture base was already
+ * added so subtract it here since scif_ioremap is going to add it again
+ */
+ if (!scifdev_self(dev) && window->type == SCIF_WINDOW_PEER &&
+ dev->sdev->aper && !dev->sdev->card_rel_da)
+ phys = phys - dev->sdev->aper->pa;
+ return scif_ioremap(phys, len, dev);
+}
+
+static inline void
+iounmap_remote(void *virt, size_t size, struct scif_copy_work *work)
+{
+ scif_iounmap(virt, size, work->remote_dev);
+}
+
+/*
+ * Takes care of ordering issue caused by
+ * 1. Hardware: Only in the case of cpu copy from mgmt node to card
+ * because of WC memory.
+ * 2. Software: If memcpy reorders copy instructions for optimization.
+ * This could happen at both mgmt node and card.
+ */
+static inline void
+scif_ordered_memcpy_toio(char *dst, const char *src, size_t count)
+{
+ if (!count)
+ return;
+
+ memcpy_toio((void __iomem __force *)dst, src, --count);
+ /* Order the last byte with the previous stores */
+ wmb();
+ *(dst + count) = *(src + count);
+}
+
+static inline void scif_unaligned_cpy_toio(char *dst, const char *src,
+ size_t count, bool ordered)
+{
+ if (ordered)
+ scif_ordered_memcpy_toio(dst, src, count);
+ else
+ memcpy_toio((void __iomem __force *)dst, src, count);
+}
+
+static inline
+void scif_ordered_memcpy_fromio(char *dst, const char *src, size_t count)
+{
+ if (!count)
+ return;
+
+ memcpy_fromio(dst, (void __iomem __force *)src, --count);
+ /* Order the last byte with the previous loads */
+ rmb();
+ *(dst + count) = *(src + count);
+}
+
+static inline void scif_unaligned_cpy_fromio(char *dst, const char *src,
+ size_t count, bool ordered)
+{
+ if (ordered)
+ scif_ordered_memcpy_fromio(dst, src, count);
+ else
+ memcpy_fromio(dst, (void __iomem __force *)src, count);
+}
+
+#define SCIF_RMA_ERROR_CODE (~(dma_addr_t)0x0)
+
+/*
+ * scif_off_to_dma_addr:
+ * Obtain the dma_addr given the window and the offset.
+ * @window: Registered window.
+ * @off: Window offset.
+ * @nr_bytes: Return the number of contiguous bytes till next DMA addr index.
+ * @index: Return the index of the dma_addr array found.
+ * @start_off: start offset of index of the dma addr array found.
+ * The nr_bytes provides the callee an estimate of the maximum possible
+ * DMA xfer possible while the index/start_off provide faster lookups
+ * for the next iteration.
+ */
+dma_addr_t scif_off_to_dma_addr(struct scif_window *window, s64 off,
+ size_t *nr_bytes, struct scif_window_iter *iter)
+{
+ int i, page_nr;
+ s64 start, end;
+ off_t page_off;
+
+ if (window->nr_pages == window->nr_contig_chunks) {
+ page_nr = (off - window->offset) >> PAGE_SHIFT;
+ page_off = off & ~PAGE_MASK;
+
+ if (nr_bytes)
+ *nr_bytes = PAGE_SIZE - page_off;
+ return window->dma_addr[page_nr] | page_off;
+ }
+ if (iter) {
+ i = iter->index;
+ start = iter->offset;
+ } else {
+ i = 0;
+ start = window->offset;
+ }
+ for (; i < window->nr_contig_chunks; i++) {
+ end = start + (window->num_pages[i] << PAGE_SHIFT);
+ if (off >= start && off < end) {
+ if (iter) {
+ iter->index = i;
+ iter->offset = start;
+ }
+ if (nr_bytes)
+ *nr_bytes = end - off;
+ return (window->dma_addr[i] + (off - start));
+ }
+ start += (window->num_pages[i] << PAGE_SHIFT);
+ }
+ dev_err(scif_info.mdev.this_device,
+ "%s %d BUG. Addr not found? window %p off 0x%llx\n",
+ __func__, __LINE__, window, off);
+ return SCIF_RMA_ERROR_CODE;
+}
+
+/*
+ * Copy between rma window and temporary buffer
+ */
+static void scif_rma_local_cpu_copy(s64 offset, struct scif_window *window,
+ u8 *temp, size_t rem_len, bool to_temp)
+{
+ void *window_virt;
+ size_t loop_len;
+ int offset_in_page;
+ s64 end_offset;
+
+ offset_in_page = offset & ~PAGE_MASK;
+ loop_len = PAGE_SIZE - offset_in_page;
+
+ if (rem_len < loop_len)
+ loop_len = rem_len;
+
+ window_virt = _get_local_va(offset, window, loop_len);
+ if (!window_virt)
+ return;
+ if (to_temp)
+ memcpy(temp, window_virt, loop_len);
+ else
+ memcpy(window_virt, temp, loop_len);
+
+ offset += loop_len;
+ temp += loop_len;
+ rem_len -= loop_len;
+
+ end_offset = window->offset +
+ (window->nr_pages << PAGE_SHIFT);
+ while (rem_len) {
+ if (offset == end_offset) {
+ window = list_entry_next(window, list);
+ end_offset = window->offset +
+ (window->nr_pages << PAGE_SHIFT);
+ }
+ loop_len = min(PAGE_SIZE, rem_len);
+ window_virt = _get_local_va(offset, window, loop_len);
+ if (!window_virt)
+ return;
+ if (to_temp)
+ memcpy(temp, window_virt, loop_len);
+ else
+ memcpy(window_virt, temp, loop_len);
+ offset += loop_len;
+ temp += loop_len;
+ rem_len -= loop_len;
+ }
+}
+
+/**
+ * scif_rma_completion_cb:
+ * @data: RMA cookie
+ *
+ * RMA interrupt completion callback.
+ */
+static void scif_rma_completion_cb(void *data)
+{
+ struct scif_dma_comp_cb *comp_cb = data;
+
+ /* Free DMA Completion CB. */
+ if (comp_cb->dst_window)
+ scif_rma_local_cpu_copy(comp_cb->dst_offset,
+ comp_cb->dst_window,
+ comp_cb->temp_buf +
+ comp_cb->header_padding,
+ comp_cb->len, false);
+ scif_unmap_single(comp_cb->temp_phys, comp_cb->sdev,
+ SCIF_KMEM_UNALIGNED_BUF_SIZE);
+ if (comp_cb->is_cache)
+ kmem_cache_free(unaligned_cache,
+ comp_cb->temp_buf_to_free);
+ else
+ kfree(comp_cb->temp_buf_to_free);
+}
+
+/* Copies between temporary buffer and offsets provided in work */
+static int
+scif_rma_list_dma_copy_unaligned(struct scif_copy_work *work,
+ u8 *temp, struct dma_chan *chan,
+ bool src_local)
+{
+ struct scif_dma_comp_cb *comp_cb = work->comp_cb;
+ dma_addr_t window_dma_addr, temp_dma_addr;
+ dma_addr_t temp_phys = comp_cb->temp_phys;
+ size_t loop_len, nr_contig_bytes = 0, remaining_len = work->len;
+ int offset_in_ca, ret = 0;
+ s64 end_offset, offset;
+ struct scif_window *window;
+ void *window_virt_addr;
+ size_t tail_len;
+ struct dma_async_tx_descriptor *tx;
+ struct dma_device *dev = chan->device;
+ dma_cookie_t cookie;
+
+ if (src_local) {
+ offset = work->dst_offset;
+ window = work->dst_window;
+ } else {
+ offset = work->src_offset;
+ window = work->src_window;
+ }
+
+ offset_in_ca = offset & (L1_CACHE_BYTES - 1);
+ if (offset_in_ca) {
+ loop_len = L1_CACHE_BYTES - offset_in_ca;
+ loop_len = min(loop_len, remaining_len);
+ window_virt_addr = ioremap_remote(offset, window,
+ loop_len,
+ work->remote_dev,
+ NULL);
+ if (!window_virt_addr)
+ return -ENOMEM;
+ if (src_local)
+ scif_unaligned_cpy_toio(window_virt_addr, temp,
+ loop_len,
+ work->ordered &&
+ !(remaining_len - loop_len));
+ else
+ scif_unaligned_cpy_fromio(temp, window_virt_addr,
+ loop_len, work->ordered &&
+ !(remaining_len - loop_len));
+ iounmap_remote(window_virt_addr, loop_len, work);
+
+ offset += loop_len;
+ temp += loop_len;
+ temp_phys += loop_len;
+ remaining_len -= loop_len;
+ }
+
+ offset_in_ca = offset & ~PAGE_MASK;
+ end_offset = window->offset +
+ (window->nr_pages << PAGE_SHIFT);
+
+ tail_len = remaining_len & (L1_CACHE_BYTES - 1);
+ remaining_len -= tail_len;
+ while (remaining_len) {
+ if (offset == end_offset) {
+ window = list_entry_next(window, list);
+ end_offset = window->offset +
+ (window->nr_pages << PAGE_SHIFT);
+ }
+ if (scif_is_mgmt_node())
+ temp_dma_addr = temp_phys;
+ else
+ /* Fix if we ever enable IOMMU on the card */
+ temp_dma_addr = (dma_addr_t)virt_to_phys(temp);
+ window_dma_addr = scif_off_to_dma_addr(window, offset,
+ &nr_contig_bytes,
+ NULL);
+ loop_len = min(nr_contig_bytes, remaining_len);
+ if (src_local) {
+ if (work->ordered && !tail_len &&
+ !(remaining_len - loop_len) &&
+ loop_len != L1_CACHE_BYTES) {
+ /*
+ * Break up the last chunk of the transfer into
+ * two steps. if there is no tail to guarantee
+ * DMA ordering. SCIF_DMA_POLLING inserts
+ * a status update descriptor in step 1 which
+ * acts as a double sided synchronization fence
+ * for the DMA engine to ensure that the last
+ * cache line in step 2 is updated last.
+ */
+ /* Step 1) DMA: Body Length - L1_CACHE_BYTES. */
+ tx =
+ dev->device_prep_dma_memcpy(chan,
+ window_dma_addr,
+ temp_dma_addr,
+ loop_len -
+ L1_CACHE_BYTES,
+ DMA_PREP_FENCE);
+ if (!tx) {
+ ret = -ENOMEM;
+ goto err;
+ }
+ cookie = tx->tx_submit(tx);
+ if (dma_submit_error(cookie)) {
+ ret = -ENOMEM;
+ goto err;
+ }
+ dma_async_issue_pending(chan);
+ offset += (loop_len - L1_CACHE_BYTES);
+ temp_dma_addr += (loop_len - L1_CACHE_BYTES);
+ window_dma_addr += (loop_len - L1_CACHE_BYTES);
+ remaining_len -= (loop_len - L1_CACHE_BYTES);
+ loop_len = remaining_len;
+
+ /* Step 2) DMA: L1_CACHE_BYTES */
+ tx =
+ dev->device_prep_dma_memcpy(chan,
+ window_dma_addr,
+ temp_dma_addr,
+ loop_len, 0);
+ if (!tx) {
+ ret = -ENOMEM;
+ goto err;
+ }
+ cookie = tx->tx_submit(tx);
+ if (dma_submit_error(cookie)) {
+ ret = -ENOMEM;
+ goto err;
+ }
+ dma_async_issue_pending(chan);
+ } else {
+ tx =
+ dev->device_prep_dma_memcpy(chan,
+ window_dma_addr,
+ temp_dma_addr,
+ loop_len, 0);
+ if (!tx) {
+ ret = -ENOMEM;
+ goto err;
+ }
+ cookie = tx->tx_submit(tx);
+ if (dma_submit_error(cookie)) {
+ ret = -ENOMEM;
+ goto err;
+ }
+ dma_async_issue_pending(chan);
+ }
+ } else {
+ tx = dev->device_prep_dma_memcpy(chan, temp_dma_addr,
+ window_dma_addr, loop_len, 0);
+ if (!tx) {
+ ret = -ENOMEM;
+ goto err;
+ }
+ cookie = tx->tx_submit(tx);
+ if (dma_submit_error(cookie)) {
+ ret = -ENOMEM;
+ goto err;
+ }
+ dma_async_issue_pending(chan);
+ }
+ if (ret < 0)
+ goto err;
+ offset += loop_len;
+ temp += loop_len;
+ temp_phys += loop_len;
+ remaining_len -= loop_len;
+ offset_in_ca = 0;
+ }
+ if (tail_len) {
+ if (offset == end_offset) {
+ window = list_entry_next(window, list);
+ end_offset = window->offset +
+ (window->nr_pages << PAGE_SHIFT);
+ }
+ window_virt_addr = ioremap_remote(offset, window, tail_len,
+ work->remote_dev,
+ NULL);
+ if (!window_virt_addr)
+ return -ENOMEM;
+ /*
+ * The CPU copy for the tail bytes must be initiated only once
+ * previous DMA transfers for this endpoint have completed
+ * to guarantee ordering.
+ */
+ if (work->ordered) {
+ struct scif_dev *rdev = work->remote_dev;
+
+ ret = scif_drain_dma_intr(rdev->sdev, chan);
+ if (ret)
+ return ret;
+ }
+ if (src_local)
+ scif_unaligned_cpy_toio(window_virt_addr, temp,
+ tail_len, work->ordered);
+ else
+ scif_unaligned_cpy_fromio(temp, window_virt_addr,
+ tail_len, work->ordered);
+ iounmap_remote(window_virt_addr, tail_len, work);
+ }
+ tx = dev->device_prep_dma_memcpy(chan, 0, 0, 0, DMA_PREP_INTERRUPT);
+ if (!tx) {
+ ret = -ENOMEM;
+ return ret;
+ }
+ tx->callback = &scif_rma_completion_cb;
+ tx->callback_param = comp_cb;
+ cookie = tx->tx_submit(tx);
+
+ if (dma_submit_error(cookie)) {
+ ret = -ENOMEM;
+ return ret;
+ }
+ dma_async_issue_pending(chan);
+ return 0;
+err:
+ dev_err(scif_info.mdev.this_device,
+ "%s %d Desc Prog Failed ret %d\n",
+ __func__, __LINE__, ret);
+ return ret;
+}
+
+/*
+ * _scif_rma_list_dma_copy_aligned:
+ *
+ * Traverse all the windows and perform DMA copy.
+ */
+static int _scif_rma_list_dma_copy_aligned(struct scif_copy_work *work,
+ struct dma_chan *chan)
+{
+ dma_addr_t src_dma_addr, dst_dma_addr;
+ size_t loop_len, remaining_len, src_contig_bytes = 0;
+ size_t dst_contig_bytes = 0;
+ struct scif_window_iter src_win_iter;
+ struct scif_window_iter dst_win_iter;
+ s64 end_src_offset, end_dst_offset;
+ struct scif_window *src_window = work->src_window;
+ struct scif_window *dst_window = work->dst_window;
+ s64 src_offset = work->src_offset, dst_offset = work->dst_offset;
+ int ret = 0;
+ struct dma_async_tx_descriptor *tx;
+ struct dma_device *dev = chan->device;
+ dma_cookie_t cookie;
+
+ remaining_len = work->len;
+
+ scif_init_window_iter(src_window, &src_win_iter);
+ scif_init_window_iter(dst_window, &dst_win_iter);
+ end_src_offset = src_window->offset +
+ (src_window->nr_pages << PAGE_SHIFT);
+ end_dst_offset = dst_window->offset +
+ (dst_window->nr_pages << PAGE_SHIFT);
+ while (remaining_len) {
+ if (src_offset == end_src_offset) {
+ src_window = list_entry_next(src_window, list);
+ end_src_offset = src_window->offset +
+ (src_window->nr_pages << PAGE_SHIFT);
+ scif_init_window_iter(src_window, &src_win_iter);
+ }
+ if (dst_offset == end_dst_offset) {
+ dst_window = list_entry_next(dst_window, list);
+ end_dst_offset = dst_window->offset +
+ (dst_window->nr_pages << PAGE_SHIFT);
+ scif_init_window_iter(dst_window, &dst_win_iter);
+ }
+
+ /* compute dma addresses for transfer */
+ src_dma_addr = scif_off_to_dma_addr(src_window, src_offset,
+ &src_contig_bytes,
+ &src_win_iter);
+ dst_dma_addr = scif_off_to_dma_addr(dst_window, dst_offset,
+ &dst_contig_bytes,
+ &dst_win_iter);
+ loop_len = min(src_contig_bytes, dst_contig_bytes);
+ loop_len = min(loop_len, remaining_len);
+ if (work->ordered && !(remaining_len - loop_len)) {
+ /*
+ * Break up the last chunk of the transfer into two
+ * steps to ensure that the last byte in step 2 is
+ * updated last.
+ */
+ /* Step 1) DMA: Body Length - 1 */
+ tx = dev->device_prep_dma_memcpy(chan, dst_dma_addr,
+ src_dma_addr,
+ loop_len - 1,
+ DMA_PREP_FENCE);
+ if (!tx) {
+ ret = -ENOMEM;
+ goto err;
+ }
+ cookie = tx->tx_submit(tx);
+ if (dma_submit_error(cookie)) {
+ ret = -ENOMEM;
+ goto err;
+ }
+ src_offset += (loop_len - 1);
+ dst_offset += (loop_len - 1);
+ src_dma_addr += (loop_len - 1);
+ dst_dma_addr += (loop_len - 1);
+ remaining_len -= (loop_len - 1);
+ loop_len = remaining_len;
+
+ /* Step 2) DMA: 1 BYTES */
+ tx = dev->device_prep_dma_memcpy(chan, dst_dma_addr,
+ src_dma_addr, loop_len, 0);
+ if (!tx) {
+ ret = -ENOMEM;
+ goto err;
+ }
+ cookie = tx->tx_submit(tx);
+ if (dma_submit_error(cookie)) {
+ ret = -ENOMEM;
+ goto err;
+ }
+ dma_async_issue_pending(chan);
+ } else {
+ tx = dev->device_prep_dma_memcpy(chan, dst_dma_addr,
+ src_dma_addr, loop_len, 0);
+ if (!tx) {
+ ret = -ENOMEM;
+ goto err;
+ }
+ cookie = tx->tx_submit(tx);
+ if (dma_submit_error(cookie)) {
+ ret = -ENOMEM;
+ goto err;
+ }
+ }
+ src_offset += loop_len;
+ dst_offset += loop_len;
+ remaining_len -= loop_len;
+ }
+ return ret;
+err:
+ dev_err(scif_info.mdev.this_device,
+ "%s %d Desc Prog Failed ret %d\n",
+ __func__, __LINE__, ret);
+ return ret;
+}
+
+/*
+ * scif_rma_list_dma_copy_aligned:
+ *
+ * Traverse all the windows and perform DMA copy.
+ */
+static int scif_rma_list_dma_copy_aligned(struct scif_copy_work *work,
+ struct dma_chan *chan)
+{
+ dma_addr_t src_dma_addr, dst_dma_addr;
+ size_t loop_len, remaining_len, tail_len, src_contig_bytes = 0;
+ size_t dst_contig_bytes = 0;
+ int src_cache_off;
+ s64 end_src_offset, end_dst_offset;
+ struct scif_window_iter src_win_iter;
+ struct scif_window_iter dst_win_iter;
+ void *src_virt, *dst_virt;
+ struct scif_window *src_window = work->src_window;
+ struct scif_window *dst_window = work->dst_window;
+ s64 src_offset = work->src_offset, dst_offset = work->dst_offset;
+ int ret = 0;
+ struct dma_async_tx_descriptor *tx;
+ struct dma_device *dev = chan->device;
+ dma_cookie_t cookie;
+
+ remaining_len = work->len;
+ scif_init_window_iter(src_window, &src_win_iter);
+ scif_init_window_iter(dst_window, &dst_win_iter);
+
+ src_cache_off = src_offset & (L1_CACHE_BYTES - 1);
+ if (src_cache_off != 0) {
+ /* Head */
+ loop_len = L1_CACHE_BYTES - src_cache_off;
+ loop_len = min(loop_len, remaining_len);
+ src_dma_addr = __scif_off_to_dma_addr(src_window, src_offset);
+ dst_dma_addr = __scif_off_to_dma_addr(dst_window, dst_offset);
+ if (src_window->type == SCIF_WINDOW_SELF)
+ src_virt = _get_local_va(src_offset, src_window,
+ loop_len);
+ else
+ src_virt = ioremap_remote(src_offset, src_window,
+ loop_len,
+ work->remote_dev, NULL);
+ if (!src_virt)
+ return -ENOMEM;
+ if (dst_window->type == SCIF_WINDOW_SELF)
+ dst_virt = _get_local_va(dst_offset, dst_window,
+ loop_len);
+ else
+ dst_virt = ioremap_remote(dst_offset, dst_window,
+ loop_len,
+ work->remote_dev, NULL);
+ if (!dst_virt) {
+ if (src_window->type != SCIF_WINDOW_SELF)
+ iounmap_remote(src_virt, loop_len, work);
+ return -ENOMEM;
+ }
+ if (src_window->type == SCIF_WINDOW_SELF)
+ scif_unaligned_cpy_toio(dst_virt, src_virt, loop_len,
+ remaining_len == loop_len ?
+ work->ordered : false);
+ else
+ scif_unaligned_cpy_fromio(dst_virt, src_virt, loop_len,
+ remaining_len == loop_len ?
+ work->ordered : false);
+ if (src_window->type != SCIF_WINDOW_SELF)
+ iounmap_remote(src_virt, loop_len, work);
+ if (dst_window->type != SCIF_WINDOW_SELF)
+ iounmap_remote(dst_virt, loop_len, work);
+ src_offset += loop_len;
+ dst_offset += loop_len;
+ remaining_len -= loop_len;
+ }
+
+ end_src_offset = src_window->offset +
+ (src_window->nr_pages << PAGE_SHIFT);
+ end_dst_offset = dst_window->offset +
+ (dst_window->nr_pages << PAGE_SHIFT);
+ tail_len = remaining_len & (L1_CACHE_BYTES - 1);
+ remaining_len -= tail_len;
+ while (remaining_len) {
+ if (src_offset == end_src_offset) {
+ src_window = list_entry_next(src_window, list);
+ end_src_offset = src_window->offset +
+ (src_window->nr_pages << PAGE_SHIFT);
+ scif_init_window_iter(src_window, &src_win_iter);
+ }
+ if (dst_offset == end_dst_offset) {
+ dst_window = list_entry_next(dst_window, list);
+ end_dst_offset = dst_window->offset +
+ (dst_window->nr_pages << PAGE_SHIFT);
+ scif_init_window_iter(dst_window, &dst_win_iter);
+ }
+
+ /* compute dma addresses for transfer */
+ src_dma_addr = scif_off_to_dma_addr(src_window, src_offset,
+ &src_contig_bytes,
+ &src_win_iter);
+ dst_dma_addr = scif_off_to_dma_addr(dst_window, dst_offset,
+ &dst_contig_bytes,
+ &dst_win_iter);
+ loop_len = min(src_contig_bytes, dst_contig_bytes);
+ loop_len = min(loop_len, remaining_len);
+ if (work->ordered && !tail_len &&
+ !(remaining_len - loop_len)) {
+ /*
+ * Break up the last chunk of the transfer into two
+ * steps. if there is no tail to gurantee DMA ordering.
+ * Passing SCIF_DMA_POLLING inserts a status update
+ * descriptor in step 1 which acts as a double sided
+ * synchronization fence for the DMA engine to ensure
+ * that the last cache line in step 2 is updated last.
+ */
+ /* Step 1) DMA: Body Length - L1_CACHE_BYTES. */
+ tx = dev->device_prep_dma_memcpy(chan, dst_dma_addr,
+ src_dma_addr,
+ loop_len -
+ L1_CACHE_BYTES,
+ DMA_PREP_FENCE);
+ if (!tx) {
+ ret = -ENOMEM;
+ goto err;
+ }
+ cookie = tx->tx_submit(tx);
+ if (dma_submit_error(cookie)) {
+ ret = -ENOMEM;
+ goto err;
+ }
+ dma_async_issue_pending(chan);
+ src_offset += (loop_len - L1_CACHE_BYTES);
+ dst_offset += (loop_len - L1_CACHE_BYTES);
+ src_dma_addr += (loop_len - L1_CACHE_BYTES);
+ dst_dma_addr += (loop_len - L1_CACHE_BYTES);
+ remaining_len -= (loop_len - L1_CACHE_BYTES);
+ loop_len = remaining_len;
+
+ /* Step 2) DMA: L1_CACHE_BYTES */
+ tx = dev->device_prep_dma_memcpy(chan, dst_dma_addr,
+ src_dma_addr,
+ loop_len, 0);
+ if (!tx) {
+ ret = -ENOMEM;
+ goto err;
+ }
+ cookie = tx->tx_submit(tx);
+ if (dma_submit_error(cookie)) {
+ ret = -ENOMEM;
+ goto err;
+ }
+ dma_async_issue_pending(chan);
+ } else {
+ tx = dev->device_prep_dma_memcpy(chan, dst_dma_addr,
+ src_dma_addr,
+ loop_len, 0);
+ if (!tx) {
+ ret = -ENOMEM;
+ goto err;
+ }
+ cookie = tx->tx_submit(tx);
+ if (dma_submit_error(cookie)) {
+ ret = -ENOMEM;
+ goto err;
+ }
+ dma_async_issue_pending(chan);
+ }
+ src_offset += loop_len;
+ dst_offset += loop_len;
+ remaining_len -= loop_len;
+ }
+ remaining_len = tail_len;
+ if (remaining_len) {
+ loop_len = remaining_len;
+ if (src_offset == end_src_offset)
+ src_window = list_entry_next(src_window, list);
+ if (dst_offset == end_dst_offset)
+ dst_window = list_entry_next(dst_window, list);
+
+ src_dma_addr = __scif_off_to_dma_addr(src_window, src_offset);
+ dst_dma_addr = __scif_off_to_dma_addr(dst_window, dst_offset);
+ /*
+ * The CPU copy for the tail bytes must be initiated only once
+ * previous DMA transfers for this endpoint have completed to
+ * guarantee ordering.
+ */
+ if (work->ordered) {
+ struct scif_dev *rdev = work->remote_dev;
+
+ ret = scif_drain_dma_poll(rdev->sdev, chan);
+ if (ret)
+ return ret;
+ }
+ if (src_window->type == SCIF_WINDOW_SELF)
+ src_virt = _get_local_va(src_offset, src_window,
+ loop_len);
+ else
+ src_virt = ioremap_remote(src_offset, src_window,
+ loop_len,
+ work->remote_dev, NULL);
+ if (!src_virt)
+ return -ENOMEM;
+
+ if (dst_window->type == SCIF_WINDOW_SELF)
+ dst_virt = _get_local_va(dst_offset, dst_window,
+ loop_len);
+ else
+ dst_virt = ioremap_remote(dst_offset, dst_window,
+ loop_len,
+ work->remote_dev, NULL);
+ if (!dst_virt) {
+ if (src_window->type != SCIF_WINDOW_SELF)
+ iounmap_remote(src_virt, loop_len, work);
+ return -ENOMEM;
+ }
+
+ if (src_window->type == SCIF_WINDOW_SELF)
+ scif_unaligned_cpy_toio(dst_virt, src_virt, loop_len,
+ work->ordered);
+ else
+ scif_unaligned_cpy_fromio(dst_virt, src_virt,
+ loop_len, work->ordered);
+ if (src_window->type != SCIF_WINDOW_SELF)
+ iounmap_remote(src_virt, loop_len, work);
+
+ if (dst_window->type != SCIF_WINDOW_SELF)
+ iounmap_remote(dst_virt, loop_len, work);
+ remaining_len -= loop_len;
+ }
+ return ret;
+err:
+ dev_err(scif_info.mdev.this_device,
+ "%s %d Desc Prog Failed ret %d\n",
+ __func__, __LINE__, ret);
+ return ret;
+}
+
+/*
+ * scif_rma_list_cpu_copy:
+ *
+ * Traverse all the windows and perform CPU copy.
+ */
+static int scif_rma_list_cpu_copy(struct scif_copy_work *work)
+{
+ void *src_virt, *dst_virt;
+ size_t loop_len, remaining_len;
+ int src_page_off, dst_page_off;
+ s64 src_offset = work->src_offset, dst_offset = work->dst_offset;
+ struct scif_window *src_window = work->src_window;
+ struct scif_window *dst_window = work->dst_window;
+ s64 end_src_offset, end_dst_offset;
+ int ret = 0;
+ struct scif_window_iter src_win_iter;
+ struct scif_window_iter dst_win_iter;
+
+ remaining_len = work->len;
+
+ scif_init_window_iter(src_window, &src_win_iter);
+ scif_init_window_iter(dst_window, &dst_win_iter);
+ while (remaining_len) {
+ src_page_off = src_offset & ~PAGE_MASK;
+ dst_page_off = dst_offset & ~PAGE_MASK;
+ loop_len = min(PAGE_SIZE -
+ max(src_page_off, dst_page_off),
+ remaining_len);
+
+ if (src_window->type == SCIF_WINDOW_SELF)
+ src_virt = _get_local_va(src_offset, src_window,
+ loop_len);
+ else
+ src_virt = ioremap_remote(src_offset, src_window,
+ loop_len,
+ work->remote_dev,
+ &src_win_iter);
+ if (!src_virt) {
+ ret = -ENOMEM;
+ goto error;
+ }
+
+ if (dst_window->type == SCIF_WINDOW_SELF)
+ dst_virt = _get_local_va(dst_offset, dst_window,
+ loop_len);
+ else
+ dst_virt = ioremap_remote(dst_offset, dst_window,
+ loop_len,
+ work->remote_dev,
+ &dst_win_iter);
+ if (!dst_virt) {
+ if (src_window->type == SCIF_WINDOW_PEER)
+ iounmap_remote(src_virt, loop_len, work);
+ ret = -ENOMEM;
+ goto error;
+ }
+
+ if (work->loopback) {
+ memcpy(dst_virt, src_virt, loop_len);
+ } else {
+ if (src_window->type == SCIF_WINDOW_SELF)
+ memcpy_toio((void __iomem __force *)dst_virt,
+ src_virt, loop_len);
+ else
+ memcpy_fromio(dst_virt,
+ (void __iomem __force *)src_virt,
+ loop_len);
+ }
+ if (src_window->type == SCIF_WINDOW_PEER)
+ iounmap_remote(src_virt, loop_len, work);
+
+ if (dst_window->type == SCIF_WINDOW_PEER)
+ iounmap_remote(dst_virt, loop_len, work);
+
+ src_offset += loop_len;
+ dst_offset += loop_len;
+ remaining_len -= loop_len;
+ if (remaining_len) {
+ end_src_offset = src_window->offset +
+ (src_window->nr_pages << PAGE_SHIFT);
+ end_dst_offset = dst_window->offset +
+ (dst_window->nr_pages << PAGE_SHIFT);
+ if (src_offset == end_src_offset) {
+ src_window = list_entry_next(src_window, list);
+ scif_init_window_iter(src_window,
+ &src_win_iter);
+ }
+ if (dst_offset == end_dst_offset) {
+ dst_window = list_entry_next(dst_window, list);
+ scif_init_window_iter(dst_window,
+ &dst_win_iter);
+ }
+ }
+ }
+error:
+ return ret;
+}
+
+static int scif_rma_list_dma_copy_wrapper(struct scif_endpt *epd,
+ struct scif_copy_work *work,
+ struct dma_chan *chan, off_t loffset)
+{
+ int src_cache_off, dst_cache_off;
+ s64 src_offset = work->src_offset, dst_offset = work->dst_offset;
+ u8 *temp = NULL;
+ bool src_local = true, dst_local = false;
+ struct scif_dma_comp_cb *comp_cb;
+ dma_addr_t src_dma_addr, dst_dma_addr;
+ int err;
+
+ if (is_dma_copy_aligned(chan->device, 1, 1, 1))
+ return _scif_rma_list_dma_copy_aligned(work, chan);
+
+ src_cache_off = src_offset & (L1_CACHE_BYTES - 1);
+ dst_cache_off = dst_offset & (L1_CACHE_BYTES - 1);
+
+ if (dst_cache_off == src_cache_off)
+ return scif_rma_list_dma_copy_aligned(work, chan);
+
+ if (work->loopback)
+ return scif_rma_list_cpu_copy(work);
+ src_dma_addr = __scif_off_to_dma_addr(work->src_window, src_offset);
+ dst_dma_addr = __scif_off_to_dma_addr(work->dst_window, dst_offset);
+ src_local = work->src_window->type == SCIF_WINDOW_SELF;
+ dst_local = work->dst_window->type == SCIF_WINDOW_SELF;
+
+ dst_local = dst_local;
+ /* Allocate dma_completion cb */
+ comp_cb = kzalloc(sizeof(*comp_cb), GFP_KERNEL);
+ if (!comp_cb)
+ goto error;
+
+ work->comp_cb = comp_cb;
+ comp_cb->cb_cookie = comp_cb;
+ comp_cb->dma_completion_func = &scif_rma_completion_cb;
+
+ if (work->len + (L1_CACHE_BYTES << 1) < SCIF_KMEM_UNALIGNED_BUF_SIZE) {
+ comp_cb->is_cache = false;
+ /* Allocate padding bytes to align to a cache line */
+ temp = kmalloc(work->len + (L1_CACHE_BYTES << 1),
+ GFP_KERNEL);
+ if (!temp)
+ goto free_comp_cb;
+ comp_cb->temp_buf_to_free = temp;
+ /* kmalloc(..) does not guarantee cache line alignment */
+ if (!IS_ALIGNED((u64)temp, L1_CACHE_BYTES))
+ temp = PTR_ALIGN(temp, L1_CACHE_BYTES);
+ } else {
+ comp_cb->is_cache = true;
+ temp = kmem_cache_alloc(unaligned_cache, GFP_KERNEL);
+ if (!temp)
+ goto free_comp_cb;
+ comp_cb->temp_buf_to_free = temp;
+ }
+
+ if (src_local) {
+ temp += dst_cache_off;
+ scif_rma_local_cpu_copy(work->src_offset, work->src_window,
+ temp, work->len, true);
+ } else {
+ comp_cb->dst_window = work->dst_window;
+ comp_cb->dst_offset = work->dst_offset;
+ work->src_offset = work->src_offset - src_cache_off;
+ comp_cb->len = work->len;
+ work->len = ALIGN(work->len + src_cache_off, L1_CACHE_BYTES);
+ comp_cb->header_padding = src_cache_off;
+ }
+ comp_cb->temp_buf = temp;
+
+ err = scif_map_single(&comp_cb->temp_phys, temp,
+ work->remote_dev, SCIF_KMEM_UNALIGNED_BUF_SIZE);
+ if (err)
+ goto free_temp_buf;
+ comp_cb->sdev = work->remote_dev;
+ if (scif_rma_list_dma_copy_unaligned(work, temp, chan, src_local) < 0)
+ goto free_temp_buf;
+ if (!src_local)
+ work->fence_type = SCIF_DMA_INTR;
+ return 0;
+free_temp_buf:
+ if (comp_cb->is_cache)
+ kmem_cache_free(unaligned_cache, comp_cb->temp_buf_to_free);
+ else
+ kfree(comp_cb->temp_buf_to_free);
+free_comp_cb:
+ kfree(comp_cb);
+error:
+ return -ENOMEM;
+}
+
+/**
+ * scif_rma_copy:
+ * @epd: end point descriptor.
+ * @loffset: offset in local registered address space to/from which to copy
+ * @addr: user virtual address to/from which to copy
+ * @len: length of range to copy
+ * @roffset: offset in remote registered address space to/from which to copy
+ * @flags: flags
+ * @dir: LOCAL->REMOTE or vice versa.
+ * @last_chunk: true if this is the last chunk of a larger transfer
+ *
+ * Validate parameters, check if src/dst registered ranges requested for copy
+ * are valid and initiate either CPU or DMA copy.
+ */
+static int scif_rma_copy(scif_epd_t epd, off_t loffset, unsigned long addr,
+ size_t len, off_t roffset, int flags,
+ enum scif_rma_dir dir, bool last_chunk)
+{
+ struct scif_endpt *ep = (struct scif_endpt *)epd;
+ struct scif_rma_req remote_req;
+ struct scif_rma_req req;
+ struct scif_window *local_window = NULL;
+ struct scif_window *remote_window = NULL;
+ struct scif_copy_work copy_work;
+ bool loopback;
+ int err = 0;
+ struct dma_chan *chan;
+ struct scif_mmu_notif *mmn = NULL;
+ bool cache = false;
+ struct device *spdev;
+
+ err = scif_verify_epd(ep);
+ if (err)
+ return err;
+
+ if (flags && !(flags & (SCIF_RMA_USECPU | SCIF_RMA_USECACHE |
+ SCIF_RMA_SYNC | SCIF_RMA_ORDERED)))
+ return -EINVAL;
+
+ loopback = scifdev_self(ep->remote_dev) ? true : false;
+ copy_work.fence_type = ((flags & SCIF_RMA_SYNC) && last_chunk) ?
+ SCIF_DMA_POLL : 0;
+ copy_work.ordered = !!((flags & SCIF_RMA_ORDERED) && last_chunk);
+
+ /* Use CPU for Mgmt node <-> Mgmt node copies */
+ if (loopback && scif_is_mgmt_node()) {
+ flags |= SCIF_RMA_USECPU;
+ copy_work.fence_type = 0x0;
+ }
+
+ cache = scif_is_set_reg_cache(flags);
+
+ remote_req.out_window = &remote_window;
+ remote_req.offset = roffset;
+ remote_req.nr_bytes = len;
+ /*
+ * If transfer is from local to remote then the remote window
+ * must be writeable and vice versa.
+ */
+ remote_req.prot = dir == SCIF_LOCAL_TO_REMOTE ? VM_WRITE : VM_READ;
+ remote_req.type = SCIF_WINDOW_PARTIAL;
+ remote_req.head = &ep->rma_info.remote_reg_list;
+
+ spdev = scif_get_peer_dev(ep->remote_dev);
+ if (IS_ERR(spdev)) {
+ err = PTR_ERR(spdev);
+ return err;
+ }
+
+ if (addr && cache) {
+ mutex_lock(&ep->rma_info.mmn_lock);
+ mmn = scif_find_mmu_notifier(current->mm, &ep->rma_info);
+ if (!mmn)
+ scif_add_mmu_notifier(current->mm, ep);
+ mutex_unlock(&ep->rma_info.mmn_lock);
+ if (IS_ERR(mmn)) {
+ scif_put_peer_dev(spdev);
+ return PTR_ERR(mmn);
+ }
+ cache = cache && !scif_rma_tc_can_cache(ep, len);
+ }
+ mutex_lock(&ep->rma_info.rma_lock);
+ if (addr) {
+ req.out_window = &local_window;
+ req.nr_bytes = ALIGN(len + (addr & ~PAGE_MASK),
+ PAGE_SIZE);
+ req.va_for_temp = addr & PAGE_MASK;
+ req.prot = (dir == SCIF_LOCAL_TO_REMOTE ?
+ VM_READ : VM_WRITE | VM_READ);
+ /* Does a valid local window exist? */
+ if (mmn) {
+ spin_lock(&ep->rma_info.tc_lock);
+ req.head = &mmn->tc_reg_list;
+ err = scif_query_tcw(ep, &req);
+ spin_unlock(&ep->rma_info.tc_lock);
+ }
+ if (!mmn || err) {
+ err = scif_register_temp(epd, req.va_for_temp,
+ req.nr_bytes, req.prot,
+ &loffset, &local_window);
+ if (err) {
+ mutex_unlock(&ep->rma_info.rma_lock);
+ goto error;
+ }
+ if (!cache)
+ goto skip_cache;
+ atomic_inc(&ep->rma_info.tcw_refcount);
+ atomic_add_return(local_window->nr_pages,
+ &ep->rma_info.tcw_total_pages);
+ if (mmn) {
+ spin_lock(&ep->rma_info.tc_lock);
+ scif_insert_tcw(local_window,
+ &mmn->tc_reg_list);
+ spin_unlock(&ep->rma_info.tc_lock);
+ }
+ }
+skip_cache:
+ loffset = local_window->offset +
+ (addr - local_window->va_for_temp);
+ } else {
+ req.out_window = &local_window;
+ req.offset = loffset;
+ /*
+ * If transfer is from local to remote then the self window
+ * must be readable and vice versa.
+ */
+ req.prot = dir == SCIF_LOCAL_TO_REMOTE ? VM_READ : VM_WRITE;
+ req.nr_bytes = len;
+ req.type = SCIF_WINDOW_PARTIAL;
+ req.head = &ep->rma_info.reg_list;
+ /* Does a valid local window exist? */
+ err = scif_query_window(&req);
+ if (err) {
+ mutex_unlock(&ep->rma_info.rma_lock);
+ goto error;
+ }
+ }
+
+ /* Does a valid remote window exist? */
+ err = scif_query_window(&remote_req);
+ if (err) {
+ mutex_unlock(&ep->rma_info.rma_lock);
+ goto error;
+ }
+
+ /*
+ * Prepare copy_work for submitting work to the DMA kernel thread
+ * or CPU copy routine.
+ */
+ copy_work.len = len;
+ copy_work.loopback = loopback;
+ copy_work.remote_dev = ep->remote_dev;
+ if (dir == SCIF_LOCAL_TO_REMOTE) {
+ copy_work.src_offset = loffset;
+ copy_work.src_window = local_window;
+ copy_work.dst_offset = roffset;
+ copy_work.dst_window = remote_window;
+ } else {
+ copy_work.src_offset = roffset;
+ copy_work.src_window = remote_window;
+ copy_work.dst_offset = loffset;
+ copy_work.dst_window = local_window;
+ }
+
+ if (flags & SCIF_RMA_USECPU) {
+ scif_rma_list_cpu_copy(&copy_work);
+ } else {
+ chan = ep->rma_info.dma_chan;
+ err = scif_rma_list_dma_copy_wrapper(epd, &copy_work,
+ chan, loffset);
+ }
+ if (addr && !cache)
+ atomic_inc(&ep->rma_info.tw_refcount);
+
+ mutex_unlock(&ep->rma_info.rma_lock);
+
+ if (last_chunk) {
+ struct scif_dev *rdev = ep->remote_dev;
+
+ if (copy_work.fence_type == SCIF_DMA_POLL)
+ err = scif_drain_dma_poll(rdev->sdev,
+ ep->rma_info.dma_chan);
+ else if (copy_work.fence_type == SCIF_DMA_INTR)
+ err = scif_drain_dma_intr(rdev->sdev,
+ ep->rma_info.dma_chan);
+ }
+
+ if (addr && !cache)
+ scif_queue_for_cleanup(local_window, &scif_info.rma);
+ scif_put_peer_dev(spdev);
+ return err;
+error:
+ if (err) {
+ if (addr && local_window && !cache)
+ scif_destroy_window(ep, local_window);
+ dev_err(scif_info.mdev.this_device,
+ "%s %d err %d len 0x%lx\n",
+ __func__, __LINE__, err, len);
+ }
+ scif_put_peer_dev(spdev);
+ return err;
+}
+
+int scif_readfrom(scif_epd_t epd, off_t loffset, size_t len,
+ off_t roffset, int flags)
+{
+ int err;
+
+ dev_dbg(scif_info.mdev.this_device,
+ "SCIFAPI readfrom: ep %p loffset 0x%lx len 0x%lx offset 0x%lx flags 0x%x\n",
+ epd, loffset, len, roffset, flags);
+ if (scif_unaligned(loffset, roffset)) {
+ while (len > SCIF_MAX_UNALIGNED_BUF_SIZE) {
+ err = scif_rma_copy(epd, loffset, 0x0,
+ SCIF_MAX_UNALIGNED_BUF_SIZE,
+ roffset, flags,
+ SCIF_REMOTE_TO_LOCAL, false);
+ if (err)
+ goto readfrom_err;
+ loffset += SCIF_MAX_UNALIGNED_BUF_SIZE;
+ roffset += SCIF_MAX_UNALIGNED_BUF_SIZE;
+ len -= SCIF_MAX_UNALIGNED_BUF_SIZE;
+ }
+ }
+ err = scif_rma_copy(epd, loffset, 0x0, len,
+ roffset, flags, SCIF_REMOTE_TO_LOCAL, true);
+readfrom_err:
+ return err;
+}
+EXPORT_SYMBOL_GPL(scif_readfrom);
+
+int scif_writeto(scif_epd_t epd, off_t loffset, size_t len,
+ off_t roffset, int flags)
+{
+ int err;
+
+ dev_dbg(scif_info.mdev.this_device,
+ "SCIFAPI writeto: ep %p loffset 0x%lx len 0x%lx roffset 0x%lx flags 0x%x\n",
+ epd, loffset, len, roffset, flags);
+ if (scif_unaligned(loffset, roffset)) {
+ while (len > SCIF_MAX_UNALIGNED_BUF_SIZE) {
+ err = scif_rma_copy(epd, loffset, 0x0,
+ SCIF_MAX_UNALIGNED_BUF_SIZE,
+ roffset, flags,
+ SCIF_LOCAL_TO_REMOTE, false);
+ if (err)
+ goto writeto_err;
+ loffset += SCIF_MAX_UNALIGNED_BUF_SIZE;
+ roffset += SCIF_MAX_UNALIGNED_BUF_SIZE;
+ len -= SCIF_MAX_UNALIGNED_BUF_SIZE;
+ }
+ }
+ err = scif_rma_copy(epd, loffset, 0x0, len,
+ roffset, flags, SCIF_LOCAL_TO_REMOTE, true);
+writeto_err:
+ return err;
+}
+EXPORT_SYMBOL_GPL(scif_writeto);
+
+int scif_vreadfrom(scif_epd_t epd, void *addr, size_t len,
+ off_t roffset, int flags)
+{
+ int err;
+
+ dev_dbg(scif_info.mdev.this_device,
+ "SCIFAPI vreadfrom: ep %p addr %p len 0x%lx roffset 0x%lx flags 0x%x\n",
+ epd, addr, len, roffset, flags);
+ if (scif_unaligned((off_t __force)addr, roffset)) {
+ if (len > SCIF_MAX_UNALIGNED_BUF_SIZE)
+ flags &= ~SCIF_RMA_USECACHE;
+
+ while (len > SCIF_MAX_UNALIGNED_BUF_SIZE) {
+ err = scif_rma_copy(epd, 0, (u64)addr,
+ SCIF_MAX_UNALIGNED_BUF_SIZE,
+ roffset, flags,
+ SCIF_REMOTE_TO_LOCAL, false);
+ if (err)
+ goto vreadfrom_err;
+ addr += SCIF_MAX_UNALIGNED_BUF_SIZE;
+ roffset += SCIF_MAX_UNALIGNED_BUF_SIZE;
+ len -= SCIF_MAX_UNALIGNED_BUF_SIZE;
+ }
+ }
+ err = scif_rma_copy(epd, 0, (u64)addr, len,
+ roffset, flags, SCIF_REMOTE_TO_LOCAL, true);
+vreadfrom_err:
+ return err;
+}
+EXPORT_SYMBOL_GPL(scif_vreadfrom);
+
+int scif_vwriteto(scif_epd_t epd, void *addr, size_t len,
+ off_t roffset, int flags)
+{
+ int err;
+
+ dev_dbg(scif_info.mdev.this_device,
+ "SCIFAPI vwriteto: ep %p addr %p len 0x%lx roffset 0x%lx flags 0x%x\n",
+ epd, addr, len, roffset, flags);
+ if (scif_unaligned((off_t __force)addr, roffset)) {
+ if (len > SCIF_MAX_UNALIGNED_BUF_SIZE)
+ flags &= ~SCIF_RMA_USECACHE;
+
+ while (len > SCIF_MAX_UNALIGNED_BUF_SIZE) {
+ err = scif_rma_copy(epd, 0, (u64)addr,
+ SCIF_MAX_UNALIGNED_BUF_SIZE,
+ roffset, flags,
+ SCIF_LOCAL_TO_REMOTE, false);
+ if (err)
+ goto vwriteto_err;
+ addr += SCIF_MAX_UNALIGNED_BUF_SIZE;
+ roffset += SCIF_MAX_UNALIGNED_BUF_SIZE;
+ len -= SCIF_MAX_UNALIGNED_BUF_SIZE;
+ }
+ }
+ err = scif_rma_copy(epd, 0, (u64)addr, len,
+ roffset, flags, SCIF_LOCAL_TO_REMOTE, true);
+vwriteto_err:
+ return err;
+}
+EXPORT_SYMBOL_GPL(scif_vwriteto);