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dmaengine: refactor dmaengine around dma_async_tx_descriptor

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The current dmaengine interface defines mutliple routines per operation,
i.e. dma_async_memcpy_buf_to_buf, dma_async_memcpy_buf_to_page etc.  Adding
more operation types (xor, crc, etc) to this model would result in an
unmanageable number of method permutations.

	Are we really going to add a set of hooks for each DMA engine
	whizbang feature?
		- Jeff Garzik

The descriptor creation process is refactored using the new common
dma_async_tx_descriptor structure.  Instead of per driver
do_<operation>_<dest>_to_<src> methods, drivers integrate
dma_async_tx_descriptor into their private software descriptor and then
define a 'prep' routine per operation.  The prep routine allocates a
descriptor and ensures that the tx_set_src, tx_set_dest, tx_submit routines
are valid.  Descriptor creation and submission becomes:

struct dma_device *dev;
struct dma_chan *chan;
struct dma_async_tx_descriptor *tx;

tx = dev->device_prep_dma_<operation>(chan, len, int_flag)
tx->tx_set_src(dma_addr_t, tx, index /* for multi-source ops */)
tx->tx_set_dest(dma_addr_t, tx, index)
tx->tx_submit(tx)

In addition to the refactoring, dma_async_tx_descriptor also lays the
groundwork for definining cross-channel-operation dependencies, and a
callback facility for asynchronous notification of operation completion.

Changelog:
* drop dma mapping methods, suggested by Chris Leech
* fix ioat_dma_dependency_added, also caught by Andrew Morton
* fix dma_sync_wait, change from Andrew Morton
* uninline large functions, change from Andrew Morton
* add tx->callback = NULL to dmaengine calls to interoperate with async_tx
  calls
* hookup ioat_tx_submit
* convert channel capabilities to a 'cpumask_t like' bitmap
* removed DMA_TX_ARRAY_INIT, no longer needed
* checkpatch.pl fixes
* make set_src, set_dest, and tx_submit descriptor specific methods
* fixup git-ioat merge
* move group_list and phys to dma_async_tx_descriptor

Cc: Jeff Garzik <jeff@garzik.org>
Cc: Chris Leech <christopher.leech@intel.com>
Signed-off-by: Shannon Nelson <shannon.nelson@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Dan Williams 2007-01-02 11:10:43 -07:00
parent 428ed6024f
commit 7405f74bad
4 changed files with 482 additions and 261 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

182
drivers/dma/dmaengine.c
View file

@ -59,6 +59,7 @@
#include <linux/init.h> #include <linux/init.h>
#include <linux/module.h> #include <linux/module.h>
#include <linux/mm.h>
#include <linux/device.h> #include <linux/device.h>
#include <linux/dmaengine.h> #include <linux/dmaengine.h>
#include <linux/hardirq.h> #include <linux/hardirq.h>
@ -66,6 +67,7 @@
#include <linux/percpu.h> #include <linux/percpu.h>
#include <linux/rcupdate.h> #include <linux/rcupdate.h>
#include <linux/mutex.h> #include <linux/mutex.h>
#include <linux/jiffies.h>
static DEFINE_MUTEX(dma_list_mutex); static DEFINE_MUTEX(dma_list_mutex);
static LIST_HEAD(dma_device_list); static LIST_HEAD(dma_device_list);
@ -165,6 +167,24 @@ static struct dma_chan *dma_client_chan_alloc(struct dma_client *client)
return NULL; return NULL;
} }
enum dma_status dma_sync_wait(struct dma_chan *chan, dma_cookie_t cookie)
{
enum dma_status status;
unsigned long dma_sync_wait_timeout = jiffies + msecs_to_jiffies(5000);
dma_async_issue_pending(chan);
do {
status = dma_async_is_tx_complete(chan, cookie, NULL, NULL);
if (time_after_eq(jiffies, dma_sync_wait_timeout)) {
printk(KERN_ERR "dma_sync_wait_timeout!\n");
return DMA_ERROR;
}
} while (status == DMA_IN_PROGRESS);
return status;
}
EXPORT_SYMBOL(dma_sync_wait);
/** /**
* dma_chan_cleanup - release a DMA channel's resources * dma_chan_cleanup - release a DMA channel's resources
* @kref: kernel reference structure that contains the DMA channel device * @kref: kernel reference structure that contains the DMA channel device
@ -322,6 +342,25 @@ int dma_async_device_register(struct dma_device *device)
if (!device) if (!device)
return -ENODEV; return -ENODEV;
/* validate device routines */
BUG_ON(dma_has_cap(DMA_MEMCPY, device->cap_mask) &&
!device->device_prep_dma_memcpy);
BUG_ON(dma_has_cap(DMA_XOR, device->cap_mask) &&
!device->device_prep_dma_xor);
BUG_ON(dma_has_cap(DMA_ZERO_SUM, device->cap_mask) &&
!device->device_prep_dma_zero_sum);
BUG_ON(dma_has_cap(DMA_MEMSET, device->cap_mask) &&
!device->device_prep_dma_memset);
BUG_ON(dma_has_cap(DMA_ZERO_SUM, device->cap_mask) &&
!device->device_prep_dma_interrupt);
BUG_ON(!device->device_alloc_chan_resources);
BUG_ON(!device->device_free_chan_resources);
BUG_ON(!device->device_dependency_added);
BUG_ON(!device->device_is_tx_complete);
BUG_ON(!device->device_issue_pending);
BUG_ON(!device->dev);
init_completion(&device->done); init_completion(&device->done);
kref_init(&device->refcount); kref_init(&device->refcount);
device->dev_id = id++; device->dev_id = id++;
@ -415,6 +454,149 @@ void dma_async_device_unregister(struct dma_device *device)
} }
EXPORT_SYMBOL(dma_async_device_unregister); EXPORT_SYMBOL(dma_async_device_unregister);
/**
* dma_async_memcpy_buf_to_buf - offloaded copy between virtual addresses
* @chan: DMA channel to offload copy to
* @dest: destination address (virtual)
* @src: source address (virtual)
* @len: length
*
* Both @dest and @src must be mappable to a bus address according to the
* DMA mapping API rules for streaming mappings.
* Both @dest and @src must stay memory resident (kernel memory or locked
* user space pages).
*/
dma_cookie_t
dma_async_memcpy_buf_to_buf(struct dma_chan *chan, void *dest,
void *src, size_t len)
{
struct dma_device *dev = chan->device;
struct dma_async_tx_descriptor *tx;
dma_addr_t addr;
dma_cookie_t cookie;
int cpu;
tx = dev->device_prep_dma_memcpy(chan, len, 0);
if (!tx)
return -ENOMEM;
tx->ack = 1;
tx->callback = NULL;
addr = dma_map_single(dev->dev, src, len, DMA_TO_DEVICE);
tx->tx_set_src(addr, tx, 0);
addr = dma_map_single(dev->dev, dest, len, DMA_FROM_DEVICE);
tx->tx_set_dest(addr, tx, 0);
cookie = tx->tx_submit(tx);
cpu = get_cpu();
per_cpu_ptr(chan->local, cpu)->bytes_transferred += len;
per_cpu_ptr(chan->local, cpu)->memcpy_count++;
put_cpu();
return cookie;
}
EXPORT_SYMBOL(dma_async_memcpy_buf_to_buf);
/**
* dma_async_memcpy_buf_to_pg - offloaded copy from address to page
* @chan: DMA channel to offload copy to
* @page: destination page
* @offset: offset in page to copy to
* @kdata: source address (virtual)
* @len: length
*
* Both @page/@offset and @kdata must be mappable to a bus address according
* to the DMA mapping API rules for streaming mappings.
* Both @page/@offset and @kdata must stay memory resident (kernel memory or
* locked user space pages)
*/
dma_cookie_t
dma_async_memcpy_buf_to_pg(struct dma_chan *chan, struct page *page,
unsigned int offset, void *kdata, size_t len)
{
struct dma_device *dev = chan->device;
struct dma_async_tx_descriptor *tx;
dma_addr_t addr;
dma_cookie_t cookie;
int cpu;
tx = dev->device_prep_dma_memcpy(chan, len, 0);
if (!tx)
return -ENOMEM;
tx->ack = 1;
tx->callback = NULL;
addr = dma_map_single(dev->dev, kdata, len, DMA_TO_DEVICE);
tx->tx_set_src(addr, tx, 0);
addr = dma_map_page(dev->dev, page, offset, len, DMA_FROM_DEVICE);
tx->tx_set_dest(addr, tx, 0);
cookie = tx->tx_submit(tx);
cpu = get_cpu();
per_cpu_ptr(chan->local, cpu)->bytes_transferred += len;
per_cpu_ptr(chan->local, cpu)->memcpy_count++;
put_cpu();
return cookie;
}
EXPORT_SYMBOL(dma_async_memcpy_buf_to_pg);
/**
* dma_async_memcpy_pg_to_pg - offloaded copy from page to page
* @chan: DMA channel to offload copy to
* @dest_pg: destination page
* @dest_off: offset in page to copy to
* @src_pg: source page
* @src_off: offset in page to copy from
* @len: length
*
* Both @dest_page/@dest_off and @src_page/@src_off must be mappable to a bus
* address according to the DMA mapping API rules for streaming mappings.
* Both @dest_page/@dest_off and @src_page/@src_off must stay memory resident
* (kernel memory or locked user space pages).
*/
dma_cookie_t
dma_async_memcpy_pg_to_pg(struct dma_chan *chan, struct page *dest_pg,
unsigned int dest_off, struct page *src_pg, unsigned int src_off,
size_t len)
{
struct dma_device *dev = chan->device;
struct dma_async_tx_descriptor *tx;
dma_addr_t addr;
dma_cookie_t cookie;
int cpu;
tx = dev->device_prep_dma_memcpy(chan, len, 0);
if (!tx)
return -ENOMEM;
tx->ack = 1;
tx->callback = NULL;
addr = dma_map_page(dev->dev, src_pg, src_off, len, DMA_TO_DEVICE);
tx->tx_set_src(addr, tx, 0);
addr = dma_map_page(dev->dev, dest_pg, dest_off, len, DMA_FROM_DEVICE);
tx->tx_set_dest(addr, tx, 0);
cookie = tx->tx_submit(tx);
cpu = get_cpu();
per_cpu_ptr(chan->local, cpu)->bytes_transferred += len;
per_cpu_ptr(chan->local, cpu)->memcpy_count++;
put_cpu();
return cookie;
}
EXPORT_SYMBOL(dma_async_memcpy_pg_to_pg);
void dma_async_tx_descriptor_init(struct dma_async_tx_descriptor *tx,
struct dma_chan *chan)
{
tx->chan = chan;
spin_lock_init(&tx->lock);
INIT_LIST_HEAD(&tx->depend_node);
INIT_LIST_HEAD(&tx->depend_list);
}
EXPORT_SYMBOL(dma_async_tx_descriptor_init);
static int __init dma_bus_init(void) static int __init dma_bus_init(void)
{ {
mutex_init(&dma_list_mutex); mutex_init(&dma_list_mutex);

295
drivers/dma/ioatdma.c
View file

@ -38,6 +38,7 @@
#define to_ioat_chan(chan) container_of(chan, struct ioat_dma_chan, common) #define to_ioat_chan(chan) container_of(chan, struct ioat_dma_chan, common)
#define to_ioat_device(dev) container_of(dev, struct ioat_device, common) #define to_ioat_device(dev) container_of(dev, struct ioat_device, common)
#define to_ioat_desc(lh) container_of(lh, struct ioat_desc_sw, node) #define to_ioat_desc(lh) container_of(lh, struct ioat_desc_sw, node)
#define tx_to_ioat_desc(tx) container_of(tx, struct ioat_desc_sw, async_tx)
/* internal functions */ /* internal functions */
static int __devinit ioat_probe(struct pci_dev *pdev, const struct pci_device_id *ent); static int __devinit ioat_probe(struct pci_dev *pdev, const struct pci_device_id *ent);
@ -78,6 +79,73 @@ static int enumerate_dma_channels(struct ioat_device *device)
return device->common.chancnt; return device->common.chancnt;
} }
static void
ioat_set_src(dma_addr_t addr, struct dma_async_tx_descriptor *tx, int index)
{
struct ioat_desc_sw *iter, *desc = tx_to_ioat_desc(tx);
struct ioat_dma_chan *ioat_chan = to_ioat_chan(tx->chan);
pci_unmap_addr_set(desc, src, addr);
list_for_each_entry(iter, &desc->async_tx.tx_list, node) {
iter->hw->src_addr = addr;
addr += ioat_chan->xfercap;
}
}
static void
ioat_set_dest(dma_addr_t addr, struct dma_async_tx_descriptor *tx, int index)
{
struct ioat_desc_sw *iter, *desc = tx_to_ioat_desc(tx);
struct ioat_dma_chan *ioat_chan = to_ioat_chan(tx->chan);
pci_unmap_addr_set(desc, dst, addr);
list_for_each_entry(iter, &desc->async_tx.tx_list, node) {
iter->hw->dst_addr = addr;
addr += ioat_chan->xfercap;
}
}
static dma_cookie_t
ioat_tx_submit(struct dma_async_tx_descriptor *tx)
{
struct ioat_dma_chan *ioat_chan = to_ioat_chan(tx->chan);
struct ioat_desc_sw *desc = tx_to_ioat_desc(tx);
int append = 0;
dma_cookie_t cookie;
struct ioat_desc_sw *group_start;
group_start = list_entry(desc->async_tx.tx_list.next,
struct ioat_desc_sw, node);
spin_lock_bh(&ioat_chan->desc_lock);
/* cookie incr and addition to used_list must be atomic */
cookie = ioat_chan->common.cookie;
cookie++;
if (cookie < 0)
cookie = 1;
ioat_chan->common.cookie = desc->async_tx.cookie = cookie;
/* write address into NextDescriptor field of last desc in chain */
to_ioat_desc(ioat_chan->used_desc.prev)->hw->next =
group_start->async_tx.phys;
list_splice_init(&desc->async_tx.tx_list, ioat_chan->used_desc.prev);
ioat_chan->pending += desc->tx_cnt;
if (ioat_chan->pending >= 4) {
append = 1;
ioat_chan->pending = 0;
}
spin_unlock_bh(&ioat_chan->desc_lock);
if (append)
writeb(IOAT_CHANCMD_APPEND,
ioat_chan->reg_base + IOAT_CHANCMD_OFFSET);
return cookie;
}
static struct ioat_desc_sw *ioat_dma_alloc_descriptor( static struct ioat_desc_sw *ioat_dma_alloc_descriptor(
struct ioat_dma_chan *ioat_chan, struct ioat_dma_chan *ioat_chan,
gfp_t flags) gfp_t flags)
@ -99,8 +167,13 @@ static struct ioat_desc_sw *ioat_dma_alloc_descriptor(
} }
memset(desc, 0, sizeof(*desc)); memset(desc, 0, sizeof(*desc));
dma_async_tx_descriptor_init(&desc_sw->async_tx, &ioat_chan->common);
desc_sw->async_tx.tx_set_src = ioat_set_src;
desc_sw->async_tx.tx_set_dest = ioat_set_dest;
desc_sw->async_tx.tx_submit = ioat_tx_submit;
INIT_LIST_HEAD(&desc_sw->async_tx.tx_list);
desc_sw->hw = desc; desc_sw->hw = desc;
desc_sw->phys = phys; desc_sw->async_tx.phys = phys;
return desc_sw; return desc_sw;
} }
@ -188,12 +261,14 @@ static void ioat_dma_free_chan_resources(struct dma_chan *chan)
list_for_each_entry_safe(desc, _desc, &ioat_chan->used_desc, node) { list_for_each_entry_safe(desc, _desc, &ioat_chan->used_desc, node) {
in_use_descs++; in_use_descs++;
list_del(&desc->node); list_del(&desc->node);
pci_pool_free(ioat_device->dma_pool, desc->hw, desc->phys); pci_pool_free(ioat_device->dma_pool, desc->hw,
desc->async_tx.phys);
kfree(desc); kfree(desc);
} }
list_for_each_entry_safe(desc, _desc, &ioat_chan->free_desc, node) { list_for_each_entry_safe(desc, _desc, &ioat_chan->free_desc, node) {
list_del(&desc->node); list_del(&desc->node);
pci_pool_free(ioat_device->dma_pool, desc->hw, desc->phys); pci_pool_free(ioat_device->dma_pool, desc->hw,
desc->async_tx.phys);
kfree(desc); kfree(desc);
} }
spin_unlock_bh(&ioat_chan->desc_lock); spin_unlock_bh(&ioat_chan->desc_lock);
@ -215,45 +290,25 @@ static void ioat_dma_free_chan_resources(struct dma_chan *chan)
writew(chanctrl, ioat_chan->reg_base + IOAT_CHANCTRL_OFFSET); writew(chanctrl, ioat_chan->reg_base + IOAT_CHANCTRL_OFFSET);
} }
/** static struct dma_async_tx_descriptor *
* do_ioat_dma_memcpy - actual function that initiates a IOAT DMA transaction ioat_dma_prep_memcpy(struct dma_chan *chan, size_t len, int int_en)
* @ioat_chan: IOAT DMA channel handle
* @dest: DMA destination address
* @src: DMA source address
* @len: transaction length in bytes
*/
static dma_cookie_t do_ioat_dma_memcpy(struct ioat_dma_chan *ioat_chan,
dma_addr_t dest,
dma_addr_t src,
size_t len)
{ {
struct ioat_desc_sw *first; struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
struct ioat_desc_sw *prev; struct ioat_desc_sw *first, *prev, *new;
struct ioat_desc_sw *new;
dma_cookie_t cookie;
LIST_HEAD(new_chain); LIST_HEAD(new_chain);
u32 copy; u32 copy;
size_t orig_len; size_t orig_len;
dma_addr_t orig_src, orig_dst; int desc_count = 0;
unsigned int desc_count = 0;
unsigned int append = 0;
if (!ioat_chan || !dest || !src)
return -EFAULT;
if (!len) if (!len)
return ioat_chan->common.cookie; return NULL;
orig_len = len; orig_len = len;
orig_src = src;
orig_dst = dest;
first = NULL; first = NULL;
prev = NULL; prev = NULL;
spin_lock_bh(&ioat_chan->desc_lock); spin_lock_bh(&ioat_chan->desc_lock);
while (len) { while (len) {
if (!list_empty(&ioat_chan->free_desc)) { if (!list_empty(&ioat_chan->free_desc)) {
new = to_ioat_desc(ioat_chan->free_desc.next); new = to_ioat_desc(ioat_chan->free_desc.next);
@ -270,140 +325,36 @@ static dma_cookie_t do_ioat_dma_memcpy(struct ioat_dma_chan *ioat_chan,
new->hw->size = copy; new->hw->size = copy;
new->hw->ctl = 0; new->hw->ctl = 0;
new->hw->src_addr = src; new->async_tx.cookie = 0;
new->hw->dst_addr = dest; new->async_tx.ack = 1;
new->cookie = 0;
/* chain together the physical address list for the HW */ /* chain together the physical address list for the HW */
if (!first) if (!first)
first = new; first = new;
else else
prev->hw->next = (u64) new->phys; prev->hw->next = (u64) new->async_tx.phys;
prev = new; prev = new;
len -= copy; len -= copy;
dest += copy;
src += copy;
list_add_tail(&new->node, &new_chain); list_add_tail(&new->node, &new_chain);
desc_count++; desc_count++;
} }
list_splice(&new_chain, &new->async_tx.tx_list);
new->hw->ctl = IOAT_DMA_DESCRIPTOR_CTL_CP_STS; new->hw->ctl = IOAT_DMA_DESCRIPTOR_CTL_CP_STS;
new->hw->next = 0; new->hw->next = 0;
new->tx_cnt = desc_count;
new->async_tx.ack = 0; /* client is in control of this ack */
new->async_tx.cookie = -EBUSY;
/* cookie incr and addition to used_list must be atomic */
cookie = ioat_chan->common.cookie;
cookie++;
if (cookie < 0)
cookie = 1;
ioat_chan->common.cookie = new->cookie = cookie;
pci_unmap_addr_set(new, src, orig_src);
pci_unmap_addr_set(new, dst, orig_dst);
pci_unmap_len_set(new, src_len, orig_len); pci_unmap_len_set(new, src_len, orig_len);
pci_unmap_len_set(new, dst_len, orig_len); pci_unmap_len_set(new, dst_len, orig_len);
/* write address into NextDescriptor field of last desc in chain */
to_ioat_desc(ioat_chan->used_desc.prev)->hw->next = first->phys;
list_splice_init(&new_chain, ioat_chan->used_desc.prev);
ioat_chan->pending += desc_count;
if (ioat_chan->pending >= 4) {
append = 1;
ioat_chan->pending = 0;
}
spin_unlock_bh(&ioat_chan->desc_lock); spin_unlock_bh(&ioat_chan->desc_lock);
if (append) return new ? &new->async_tx : NULL;
writeb(IOAT_CHANCMD_APPEND,
ioat_chan->reg_base + IOAT_CHANCMD_OFFSET);
return cookie;
} }
/**
* ioat_dma_memcpy_buf_to_buf - wrapper that takes src & dest bufs
* @chan: IOAT DMA channel handle
* @dest: DMA destination address
* @src: DMA source address
* @len: transaction length in bytes
*/
static dma_cookie_t ioat_dma_memcpy_buf_to_buf(struct dma_chan *chan,
void *dest,
void *src,
size_t len)
{
dma_addr_t dest_addr;
dma_addr_t src_addr;
struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
dest_addr = pci_map_single(ioat_chan->device->pdev,
dest, len, PCI_DMA_FROMDEVICE);
src_addr = pci_map_single(ioat_chan->device->pdev,
src, len, PCI_DMA_TODEVICE);
return do_ioat_dma_memcpy(ioat_chan, dest_addr, src_addr, len);
}
/**
* ioat_dma_memcpy_buf_to_pg - wrapper, copying from a buf to a page
* @chan: IOAT DMA channel handle
* @page: pointer to the page to copy to
* @offset: offset into that page
* @src: DMA source address
* @len: transaction length in bytes
*/
static dma_cookie_t ioat_dma_memcpy_buf_to_pg(struct dma_chan *chan,
struct page *page,
unsigned int offset,
void *src,
size_t len)
{
dma_addr_t dest_addr;
dma_addr_t src_addr;
struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
dest_addr = pci_map_page(ioat_chan->device->pdev,
page, offset, len, PCI_DMA_FROMDEVICE);
src_addr = pci_map_single(ioat_chan->device->pdev,
src, len, PCI_DMA_TODEVICE);
return do_ioat_dma_memcpy(ioat_chan, dest_addr, src_addr, len);
}
/**
* ioat_dma_memcpy_pg_to_pg - wrapper, copying between two pages
* @chan: IOAT DMA channel handle
* @dest_pg: pointer to the page to copy to
* @dest_off: offset into that page
* @src_pg: pointer to the page to copy from
* @src_off: offset into that page
* @len: transaction length in bytes. This is guaranteed not to make a copy
* across a page boundary.
*/
static dma_cookie_t ioat_dma_memcpy_pg_to_pg(struct dma_chan *chan,
struct page *dest_pg,
unsigned int dest_off,
struct page *src_pg,
unsigned int src_off,
size_t len)
{
dma_addr_t dest_addr;
dma_addr_t src_addr;
struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
dest_addr = pci_map_page(ioat_chan->device->pdev,
dest_pg, dest_off, len, PCI_DMA_FROMDEVICE);
src_addr = pci_map_page(ioat_chan->device->pdev,
src_pg, src_off, len, PCI_DMA_TODEVICE);
return do_ioat_dma_memcpy(ioat_chan, dest_addr, src_addr, len);
}
/** /**
* ioat_dma_memcpy_issue_pending - push potentially unrecognized appended descriptors to hw * ioat_dma_memcpy_issue_pending - push potentially unrecognized appended descriptors to hw
@ -465,8 +416,8 @@ static void ioat_dma_memcpy_cleanup(struct ioat_dma_chan *chan)
* exceeding xfercap, perhaps. If so, only the last one will * exceeding xfercap, perhaps. If so, only the last one will
* have a cookie, and require unmapping. * have a cookie, and require unmapping.
*/ */
if (desc->cookie) { if (desc->async_tx.cookie) {
cookie = desc->cookie; cookie = desc->async_tx.cookie;
/* yes we are unmapping both _page and _single alloc'd /* yes we are unmapping both _page and _single alloc'd
regions with unmap_page. Is this *really* that bad? regions with unmap_page. Is this *really* that bad?
@ -481,14 +432,19 @@ static void ioat_dma_memcpy_cleanup(struct ioat_dma_chan *chan)
PCI_DMA_TODEVICE); PCI_DMA_TODEVICE);
} }
if (desc->phys != phys_complete) { if (desc->async_tx.phys != phys_complete) {
/* a completed entry, but not the last, so cleanup */ /* a completed entry, but not the last, so cleanup
list_del(&desc->node); * if the client is done with the descriptor
list_add_tail(&desc->node, &chan->free_desc); */
if (desc->async_tx.ack) {
list_del(&desc->node);
list_add_tail(&desc->node, &chan->free_desc);
} else
desc->async_tx.cookie = 0;
} else { } else {
/* last used desc. Do not remove, so we can append from /* last used desc. Do not remove, so we can append from
it, but don't look at it next time, either */ it, but don't look at it next time, either */
desc->cookie = 0; desc->async_tx.cookie = 0;
/* TODO check status bits? */ /* TODO check status bits? */
break; break;
@ -504,6 +460,17 @@ static void ioat_dma_memcpy_cleanup(struct ioat_dma_chan *chan)
spin_unlock(&chan->cleanup_lock); spin_unlock(&chan->cleanup_lock);
} }
static void ioat_dma_dependency_added(struct dma_chan *chan)
{
struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
spin_lock_bh(&ioat_chan->desc_lock);
if (ioat_chan->pending == 0) {
spin_unlock_bh(&ioat_chan->desc_lock);
ioat_dma_memcpy_cleanup(ioat_chan);
} else
spin_unlock_bh(&ioat_chan->desc_lock);
}
/** /**
* ioat_dma_is_complete - poll the status of a IOAT DMA transaction * ioat_dma_is_complete - poll the status of a IOAT DMA transaction
* @chan: IOAT DMA channel handle * @chan: IOAT DMA channel handle
@ -606,13 +573,14 @@ static void ioat_start_null_desc(struct ioat_dma_chan *ioat_chan)
desc->hw->ctl = IOAT_DMA_DESCRIPTOR_NUL; desc->hw->ctl = IOAT_DMA_DESCRIPTOR_NUL;
desc->hw->next = 0; desc->hw->next = 0;
desc->async_tx.ack = 1;
list_add_tail(&desc->node, &ioat_chan->used_desc); list_add_tail(&desc->node, &ioat_chan->used_desc);
spin_unlock_bh(&ioat_chan->desc_lock); spin_unlock_bh(&ioat_chan->desc_lock);
writel(((u64) desc->phys) & 0x00000000FFFFFFFF, writel(((u64) desc->async_tx.phys) & 0x00000000FFFFFFFF,
ioat_chan->reg_base + IOAT_CHAINADDR_OFFSET_LOW); ioat_chan->reg_base + IOAT_CHAINADDR_OFFSET_LOW);
writel(((u64) desc->phys) >> 32, writel(((u64) desc->async_tx.phys) >> 32,
ioat_chan->reg_base + IOAT_CHAINADDR_OFFSET_HIGH); ioat_chan->reg_base + IOAT_CHAINADDR_OFFSET_HIGH);
writeb(IOAT_CHANCMD_START, ioat_chan->reg_base + IOAT_CHANCMD_OFFSET); writeb(IOAT_CHANCMD_START, ioat_chan->reg_base + IOAT_CHANCMD_OFFSET);
@ -629,6 +597,8 @@ static int ioat_self_test(struct ioat_device *device)
u8 *src; u8 *src;
u8 *dest; u8 *dest;
struct dma_chan *dma_chan; struct dma_chan *dma_chan;
struct dma_async_tx_descriptor *tx;
dma_addr_t addr;
dma_cookie_t cookie; dma_cookie_t cookie;
int err = 0; int err = 0;
@ -654,7 +624,15 @@ static int ioat_self_test(struct ioat_device *device)
goto out; goto out;
} }
cookie = ioat_dma_memcpy_buf_to_buf(dma_chan, dest, src, IOAT_TEST_SIZE); tx = ioat_dma_prep_memcpy(dma_chan, IOAT_TEST_SIZE, 0);
async_tx_ack(tx);
addr = dma_map_single(dma_chan->device->dev, src, IOAT_TEST_SIZE,
DMA_TO_DEVICE);
ioat_set_src(addr, tx, 0);
addr = dma_map_single(dma_chan->device->dev, dest, IOAT_TEST_SIZE,
DMA_FROM_DEVICE);
ioat_set_dest(addr, tx, 0);
cookie = ioat_tx_submit(tx);
ioat_dma_memcpy_issue_pending(dma_chan); ioat_dma_memcpy_issue_pending(dma_chan);
msleep(1); msleep(1);
@ -750,13 +728,14 @@ static int __devinit ioat_probe(struct pci_dev *pdev,
INIT_LIST_HEAD(&device->common.channels); INIT_LIST_HEAD(&device->common.channels);
enumerate_dma_channels(device); enumerate_dma_channels(device);
dma_cap_set(DMA_MEMCPY, device->common.cap_mask);
device->common.device_alloc_chan_resources = ioat_dma_alloc_chan_resources; device->common.device_alloc_chan_resources = ioat_dma_alloc_chan_resources;
device->common.device_free_chan_resources = ioat_dma_free_chan_resources; device->common.device_free_chan_resources = ioat_dma_free_chan_resources;
device->common.device_memcpy_buf_to_buf = ioat_dma_memcpy_buf_to_buf; device->common.device_prep_dma_memcpy = ioat_dma_prep_memcpy;
device->common.device_memcpy_buf_to_pg = ioat_dma_memcpy_buf_to_pg; device->common.device_is_tx_complete = ioat_dma_is_complete;
device->common.device_memcpy_pg_to_pg = ioat_dma_memcpy_pg_to_pg; device->common.device_issue_pending = ioat_dma_memcpy_issue_pending;
device->common.device_memcpy_complete = ioat_dma_is_complete; device->common.device_dependency_added = ioat_dma_dependency_added;
device->common.device_memcpy_issue_pending = ioat_dma_memcpy_issue_pending; device->common.dev = &pdev->dev;
printk(KERN_INFO "Intel(R) I/OAT DMA Engine found, %d channels\n", printk(KERN_INFO "Intel(R) I/OAT DMA Engine found, %d channels\n",
device->common.chancnt); device->common.chancnt);

13
drivers/dma/ioatdma.h
View file

@ -105,21 +105,20 @@ struct ioat_dma_chan {
/** /**
* struct ioat_desc_sw - wrapper around hardware descriptor * struct ioat_desc_sw - wrapper around hardware descriptor
* @hw: hardware DMA descriptor * @hw: hardware DMA descriptor
* @node: * @node: this descriptor will either be on the free list,
* @cookie: * or attached to a transaction list (async_tx.tx_list)
* @phys: * @tx_cnt: number of descriptors required to complete the transaction
* @async_tx: the generic software descriptor for all engines
*/ */
struct ioat_desc_sw { struct ioat_desc_sw {
struct ioat_dma_descriptor *hw; struct ioat_dma_descriptor *hw;
struct list_head node; struct list_head node;
dma_cookie_t cookie; int tx_cnt;
dma_addr_t phys;
DECLARE_PCI_UNMAP_ADDR(src) DECLARE_PCI_UNMAP_ADDR(src)
DECLARE_PCI_UNMAP_LEN(src_len) DECLARE_PCI_UNMAP_LEN(src_len)
DECLARE_PCI_UNMAP_ADDR(dst) DECLARE_PCI_UNMAP_ADDR(dst)
DECLARE_PCI_UNMAP_LEN(dst_len) DECLARE_PCI_UNMAP_LEN(dst_len)
struct dma_async_tx_descriptor async_tx;
}; };
#endif /* IOATDMA_H */ #endif /* IOATDMA_H */

253
include/linux/dmaengine.h
View file

@ -21,13 +21,12 @@
#ifndef DMAENGINE_H #ifndef DMAENGINE_H
#define DMAENGINE_H #define DMAENGINE_H
#ifdef CONFIG_DMA_ENGINE
#include <linux/device.h> #include <linux/device.h>
#include <linux/uio.h> #include <linux/uio.h>
#include <linux/kref.h> #include <linux/kref.h>
#include <linux/completion.h> #include <linux/completion.h>
#include <linux/rcupdate.h> #include <linux/rcupdate.h>
#include <linux/dma-mapping.h>
/** /**
* enum dma_event - resource PNP/power managment events * enum dma_event - resource PNP/power managment events
@ -64,6 +63,31 @@ enum dma_status {
DMA_ERROR, DMA_ERROR,
}; };
/**
* enum dma_transaction_type - DMA transaction types/indexes
*/
enum dma_transaction_type {
DMA_MEMCPY,
DMA_XOR,
DMA_PQ_XOR,
DMA_DUAL_XOR,
DMA_PQ_UPDATE,
DMA_ZERO_SUM,
DMA_PQ_ZERO_SUM,
DMA_MEMSET,
DMA_MEMCPY_CRC32C,
DMA_INTERRUPT,
};
/* last transaction type for creation of the capabilities mask */
#define DMA_TX_TYPE_END (DMA_INTERRUPT + 1)
/**
* dma_cap_mask_t - capabilities bitmap modeled after cpumask_t.
* See linux/cpumask.h
*/
typedef struct { DECLARE_BITMAP(bits, DMA_TX_TYPE_END); } dma_cap_mask_t;
/** /**
* struct dma_chan_percpu - the per-CPU part of struct dma_chan * struct dma_chan_percpu - the per-CPU part of struct dma_chan
* @refcount: local_t used for open-coded "bigref" counting * @refcount: local_t used for open-coded "bigref" counting
@ -157,48 +181,106 @@ struct dma_client {
struct list_head global_node; struct list_head global_node;
}; };
typedef void (*dma_async_tx_callback)(void *dma_async_param);
/**
* struct dma_async_tx_descriptor - async transaction descriptor
* ---dma generic offload fields---
* @cookie: tracking cookie for this transaction, set to -EBUSY if
* this tx is sitting on a dependency list
* @ack: the descriptor can not be reused until the client acknowledges
* receipt, i.e. has has a chance to establish any dependency chains
* @phys: physical address of the descriptor
* @tx_list: driver common field for operations that require multiple
* descriptors
* @chan: target channel for this operation
* @tx_submit: set the prepared descriptor(s) to be executed by the engine
* @tx_set_dest: set a destination address in a hardware descriptor
* @tx_set_src: set a source address in a hardware descriptor
* @callback: routine to call after this operation is complete
* @callback_param: general parameter to pass to the callback routine
* ---async_tx api specific fields---
* @depend_list: at completion this list of transactions are submitted
* @depend_node: allow this transaction to be executed after another
* transaction has completed, possibly on another channel
* @parent: pointer to the next level up in the dependency chain
* @lock: protect the dependency list
*/
struct dma_async_tx_descriptor {
dma_cookie_t cookie;
int ack;
dma_addr_t phys;
struct list_head tx_list;
struct dma_chan *chan;
dma_cookie_t (*tx_submit)(struct dma_async_tx_descriptor *tx);
void (*tx_set_dest)(dma_addr_t addr,
struct dma_async_tx_descriptor *tx, int index);
void (*tx_set_src)(dma_addr_t addr,
struct dma_async_tx_descriptor *tx, int index);
dma_async_tx_callback callback;
void *callback_param;
struct list_head depend_list;
struct list_head depend_node;
struct dma_async_tx_descriptor *parent;
spinlock_t lock;
};
/** /**
* struct dma_device - info on the entity supplying DMA services * struct dma_device - info on the entity supplying DMA services
* @chancnt: how many DMA channels are supported * @chancnt: how many DMA channels are supported
* @channels: the list of struct dma_chan * @channels: the list of struct dma_chan
* @global_node: list_head for global dma_device_list * @global_node: list_head for global dma_device_list
* @cap_mask: one or more dma_capability flags
* @max_xor: maximum number of xor sources, 0 if no capability
* @refcount: reference count * @refcount: reference count
* @done: IO completion struct * @done: IO completion struct
* @dev_id: unique device ID * @dev_id: unique device ID
* @dev: struct device reference for dma mapping api
* @device_alloc_chan_resources: allocate resources and return the * @device_alloc_chan_resources: allocate resources and return the
* number of allocated descriptors * number of allocated descriptors
* @device_free_chan_resources: release DMA channel's resources * @device_free_chan_resources: release DMA channel's resources
* @device_memcpy_buf_to_buf: memcpy buf pointer to buf pointer * @device_prep_dma_memcpy: prepares a memcpy operation
* @device_memcpy_buf_to_pg: memcpy buf pointer to struct page * @device_prep_dma_xor: prepares a xor operation
* @device_memcpy_pg_to_pg: memcpy struct page/offset to struct page/offset * @device_prep_dma_zero_sum: prepares a zero_sum operation
* @device_memcpy_complete: poll the status of an IOAT DMA transaction * @device_prep_dma_memset: prepares a memset operation
* @device_memcpy_issue_pending: push appended descriptors to hardware * @device_prep_dma_interrupt: prepares an end of chain interrupt operation
* @device_dependency_added: async_tx notifies the channel about new deps
* @device_issue_pending: push pending transactions to hardware
*/ */
struct dma_device { struct dma_device {
unsigned int chancnt; unsigned int chancnt;
struct list_head channels; struct list_head channels;
struct list_head global_node; struct list_head global_node;
dma_cap_mask_t cap_mask;
int max_xor;
struct kref refcount; struct kref refcount;
struct completion done; struct completion done;
int dev_id; int dev_id;
struct device *dev;
int (*device_alloc_chan_resources)(struct dma_chan *chan); int (*device_alloc_chan_resources)(struct dma_chan *chan);
void (*device_free_chan_resources)(struct dma_chan *chan); void (*device_free_chan_resources)(struct dma_chan *chan);
dma_cookie_t (*device_memcpy_buf_to_buf)(struct dma_chan *chan,
void *dest, void *src, size_t len); struct dma_async_tx_descriptor *(*device_prep_dma_memcpy)(
dma_cookie_t (*device_memcpy_buf_to_pg)(struct dma_chan *chan, struct dma_chan *chan, size_t len, int int_en);
struct page *page, unsigned int offset, void *kdata, struct dma_async_tx_descriptor *(*device_prep_dma_xor)(
size_t len); struct dma_chan *chan, unsigned int src_cnt, size_t len,
dma_cookie_t (*device_memcpy_pg_to_pg)(struct dma_chan *chan, int int_en);
struct page *dest_pg, unsigned int dest_off, struct dma_async_tx_descriptor *(*device_prep_dma_zero_sum)(
struct page *src_pg, unsigned int src_off, size_t len); struct dma_chan *chan, unsigned int src_cnt, size_t len,
enum dma_status (*device_memcpy_complete)(struct dma_chan *chan, u32 *result, int int_en);
struct dma_async_tx_descriptor *(*device_prep_dma_memset)(
struct dma_chan *chan, int value, size_t len, int int_en);
struct dma_async_tx_descriptor *(*device_prep_dma_interrupt)(
struct dma_chan *chan);
void (*device_dependency_added)(struct dma_chan *chan);
enum dma_status (*device_is_tx_complete)(struct dma_chan *chan,
dma_cookie_t cookie, dma_cookie_t *last, dma_cookie_t cookie, dma_cookie_t *last,
dma_cookie_t *used); dma_cookie_t *used);
void (*device_memcpy_issue_pending)(struct dma_chan *chan); void (*device_issue_pending)(struct dma_chan *chan);
}; };
/* --- public DMA engine API --- */ /* --- public DMA engine API --- */
@ -207,96 +289,72 @@ struct dma_client *dma_async_client_register(dma_event_callback event_callback);
void dma_async_client_unregister(struct dma_client *client); void dma_async_client_unregister(struct dma_client *client);
void dma_async_client_chan_request(struct dma_client *client, void dma_async_client_chan_request(struct dma_client *client,
unsigned int number); unsigned int number);
dma_cookie_t dma_async_memcpy_buf_to_buf(struct dma_chan *chan,
/** void *dest, void *src, size_t len);
* dma_async_memcpy_buf_to_buf - offloaded copy between virtual addresses dma_cookie_t dma_async_memcpy_buf_to_pg(struct dma_chan *chan,
* @chan: DMA channel to offload copy to struct page *page, unsigned int offset, void *kdata, size_t len);
* @dest: destination address (virtual) dma_cookie_t dma_async_memcpy_pg_to_pg(struct dma_chan *chan,
* @src: source address (virtual)
* @len: length
*
* Both @dest and @src must be mappable to a bus address according to the
* DMA mapping API rules for streaming mappings.
* Both @dest and @src must stay memory resident (kernel memory or locked
* user space pages).
*/
static inline dma_cookie_t dma_async_memcpy_buf_to_buf(struct dma_chan *chan,
void *dest, void *src, size_t len)
{
int cpu = get_cpu();
per_cpu_ptr(chan->local, cpu)->bytes_transferred += len;
per_cpu_ptr(chan->local, cpu)->memcpy_count++;
put_cpu();
return chan->device->device_memcpy_buf_to_buf(chan, dest, src, len);
}
/**
* dma_async_memcpy_buf_to_pg - offloaded copy from address to page
* @chan: DMA channel to offload copy to
* @page: destination page
* @offset: offset in page to copy to
* @kdata: source address (virtual)
* @len: length
*
* Both @page/@offset and @kdata must be mappable to a bus address according
* to the DMA mapping API rules for streaming mappings.
* Both @page/@offset and @kdata must stay memory resident (kernel memory or
* locked user space pages)
*/
static inline dma_cookie_t dma_async_memcpy_buf_to_pg(struct dma_chan *chan,
struct page *page, unsigned int offset, void *kdata, size_t len)
{
int cpu = get_cpu();
per_cpu_ptr(chan->local, cpu)->bytes_transferred += len;
per_cpu_ptr(chan->local, cpu)->memcpy_count++;
put_cpu();
return chan->device->device_memcpy_buf_to_pg(chan, page, offset,
kdata, len);
}
/**
* dma_async_memcpy_pg_to_pg - offloaded copy from page to page
* @chan: DMA channel to offload copy to
* @dest_pg: destination page
* @dest_off: offset in page to copy to
* @src_pg: source page
* @src_off: offset in page to copy from
* @len: length
*
* Both @dest_page/@dest_off and @src_page/@src_off must be mappable to a bus
* address according to the DMA mapping API rules for streaming mappings.
* Both @dest_page/@dest_off and @src_page/@src_off must stay memory resident
* (kernel memory or locked user space pages).
*/
static inline dma_cookie_t dma_async_memcpy_pg_to_pg(struct dma_chan *chan,
struct page *dest_pg, unsigned int dest_off, struct page *src_pg, struct page *dest_pg, unsigned int dest_off, struct page *src_pg,
unsigned int src_off, size_t len) unsigned int src_off, size_t len);
{ void dma_async_tx_descriptor_init(struct dma_async_tx_descriptor *tx,
int cpu = get_cpu(); struct dma_chan *chan);
per_cpu_ptr(chan->local, cpu)->bytes_transferred += len;
per_cpu_ptr(chan->local, cpu)->memcpy_count++;
put_cpu();
return chan->device->device_memcpy_pg_to_pg(chan, dest_pg, dest_off,
src_pg, src_off, len); static inline void
async_tx_ack(struct dma_async_tx_descriptor *tx)
{
tx->ack = 1;
} }
#define first_dma_cap(mask) __first_dma_cap(&(mask))
static inline int __first_dma_cap(const dma_cap_mask_t *srcp)
{
return min_t(int, DMA_TX_TYPE_END,
find_first_bit(srcp->bits, DMA_TX_TYPE_END));
}
#define next_dma_cap(n, mask) __next_dma_cap((n), &(mask))
static inline int __next_dma_cap(int n, const dma_cap_mask_t *srcp)
{
return min_t(int, DMA_TX_TYPE_END,
find_next_bit(srcp->bits, DMA_TX_TYPE_END, n+1));
}
#define dma_cap_set(tx, mask) __dma_cap_set((tx), &(mask))
static inline void
__dma_cap_set(enum dma_transaction_type tx_type, dma_cap_mask_t *dstp)
{
set_bit(tx_type, dstp->bits);
}
#define dma_has_cap(tx, mask) __dma_has_cap((tx), &(mask))
static inline int
__dma_has_cap(enum dma_transaction_type tx_type, dma_cap_mask_t *srcp)
{
return test_bit(tx_type, srcp->bits);
}
#define for_each_dma_cap_mask(cap, mask) \
for ((cap) = first_dma_cap(mask); \
(cap) < DMA_TX_TYPE_END; \
(cap) = next_dma_cap((cap), (mask)))
/** /**
* dma_async_memcpy_issue_pending - flush pending copies to HW * dma_async_issue_pending - flush pending transactions to HW
* @chan: target DMA channel * @chan: target DMA channel
* *
* This allows drivers to push copies to HW in batches, * This allows drivers to push copies to HW in batches,
* reducing MMIO writes where possible. * reducing MMIO writes where possible.
*/ */
static inline void dma_async_memcpy_issue_pending(struct dma_chan *chan) static inline void dma_async_issue_pending(struct dma_chan *chan)
{ {
return chan->device->device_memcpy_issue_pending(chan); return chan->device->device_issue_pending(chan);
} }
#define dma_async_memcpy_issue_pending(chan) dma_async_issue_pending(chan)
/** /**
* dma_async_memcpy_complete - poll for transaction completion * dma_async_is_tx_complete - poll for transaction completion
* @chan: DMA channel * @chan: DMA channel
* @cookie: transaction identifier to check status of * @cookie: transaction identifier to check status of
* @last: returns last completed cookie, can be NULL * @last: returns last completed cookie, can be NULL
@ -306,12 +364,15 @@ static inline void dma_async_memcpy_issue_pending(struct dma_chan *chan)
* internal state and can be used with dma_async_is_complete() to check * internal state and can be used with dma_async_is_complete() to check
* the status of multiple cookies without re-checking hardware state. * the status of multiple cookies without re-checking hardware state.
*/ */
static inline enum dma_status dma_async_memcpy_complete(struct dma_chan *chan, static inline enum dma_status dma_async_is_tx_complete(struct dma_chan *chan,
dma_cookie_t cookie, dma_cookie_t *last, dma_cookie_t *used) dma_cookie_t cookie, dma_cookie_t *last, dma_cookie_t *used)
{ {
return chan->device->device_memcpy_complete(chan, cookie, last, used); return chan->device->device_is_tx_complete(chan, cookie, last, used);
} }
#define dma_async_memcpy_complete(chan, cookie, last, used)\
dma_async_is_tx_complete(chan, cookie, last, used)
/** /**
* dma_async_is_complete - test a cookie against chan state * dma_async_is_complete - test a cookie against chan state
* @cookie: transaction identifier to test status of * @cookie: transaction identifier to test status of
@ -334,6 +395,7 @@ static inline enum dma_status dma_async_is_complete(dma_cookie_t cookie,
return DMA_IN_PROGRESS; return DMA_IN_PROGRESS;
} }
enum dma_status dma_sync_wait(struct dma_chan *chan, dma_cookie_t cookie);
/* --- DMA device --- */ /* --- DMA device --- */
@ -362,5 +424,4 @@ dma_cookie_t dma_memcpy_pg_to_iovec(struct dma_chan *chan, struct iovec *iov,
struct dma_pinned_list *pinned_list, struct page *page, struct dma_pinned_list *pinned_list, struct page *page,
unsigned int offset, size_t len); unsigned int offset, size_t len);
#endif /* CONFIG_DMA_ENGINE */
#endif /* DMAENGINE_H */ #endif /* DMAENGINE_H */