https://github.com/torvalds/linux
Tip revision: 7a308bb3016f57e5be11a677d15b821536419d36 authored by Linus Torvalds on 22 January 2017, 20:54:15 UTC
Linux 4.10-rc5
Linux 4.10-rc5
Tip revision: 7a308bb
scif_dma.c
/*
* 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;
};
/**
* 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,
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);
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, 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, 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;
list_for_each_entry(mmn, &rma->mmn_list, 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_next_entry(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_next_entry(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_next_entry(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_next_entry(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_next_entry(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_next_entry(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_next_entry(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_next_entry(src_window, list);
if (dst_offset == end_dst_offset)
dst_window = list_next_entry(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_next_entry(src_window, list);
scif_init_window_iter(src_window,
&src_win_iter);
}
if (dst_offset == end_dst_offset) {
dst_window = list_next_entry(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)
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(©_work);
} else {
chan = ep->rma_info.dma_chan;
err = scif_rma_list_dma_copy_wrapper(epd, ©_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);