Merge branch 'pci/p2pdma'

- Move P2PCMA PCI bus offset from generic dev_pagemap to
    pci_p2pdma_pagemap (Logan Gunthorpe)

  - Add provider's pci_dev to pci_p2pdma_pagemap (Logan Gunthorpe)

  - Apply host bridge whitelist for ACS (Logan Gunthorpe)

  - Whitelist some Intel host bridges for P2PDMA (Logan Gunthorpe)

  - Add attrs to pci_p2pdma_map_sg() to match dma_map_sg() (Logan
    Gunthorpe)

  - Add pci_p2pdma_unmap_sg() (Logan Gunthorpe)

  - Store P2PDMA mapping method in xarray (Logan Gunthorpe)

  - Map requests that traverse a host bridge (Logan Gunthorpe)

  - Allow IOMMU for host bridge whitelist (Logan Gunthorpe)

* pci/p2pdma:
  PCI/P2PDMA: Update pci_p2pdma_distance_many() documentation
  PCI/P2PDMA: Allow IOMMU for host bridge whitelist
  PCI/P2PDMA: dma_map() requests that traverse the host bridge
  PCI/P2PDMA: Store mapping method in an xarray
  PCI/P2PDMA: Factor out __pci_p2pdma_map_sg()
  PCI/P2PDMA: Introduce pci_p2pdma_unmap_sg()
  PCI/P2PDMA: Add attrs argument to pci_p2pdma_map_sg()
  PCI/P2PDMA: Whitelist some Intel host bridges
  PCI/P2PDMA: Factor out host_bridge_whitelist()
  PCI/P2PDMA: Apply host bridge whitelist for ACS
  PCI/P2PDMA: Factor out __upstream_bridge_distance()
  PCI/P2PDMA: Add constants for map type results to upstream_bridge_distance()
  PCI/P2PDMA: Add provider's pci_dev to pci_p2pdma_pagemap struct
  PCI/P2PDMA: Introduce private pagemap structure
This commit is contained in:
Bjorn Helgaas 2019-09-23 16:10:12 -05:00
commit 63fa8437cb
5 changed files with 302 additions and 121 deletions

View File

@ -583,8 +583,10 @@ void rdma_rw_ctx_destroy(struct rdma_rw_ctx *ctx, struct ib_qp *qp, u8 port_num,
break;
}
/* P2PDMA contexts do not need to be unmapped */
if (!is_pci_p2pdma_page(sg_page(sg)))
if (is_pci_p2pdma_page(sg_page(sg)))
pci_p2pdma_unmap_sg(qp->pd->device->dma_device, sg,
sg_cnt, dir);
else
ib_dma_unmap_sg(qp->pd->device, sg, sg_cnt, dir);
}
EXPORT_SYMBOL(rdma_rw_ctx_destroy);

View File

@ -547,8 +547,10 @@ static void nvme_unmap_data(struct nvme_dev *dev, struct request *req)
WARN_ON_ONCE(!iod->nents);
/* P2PDMA requests do not need to be unmapped */
if (!is_pci_p2pdma_page(sg_page(iod->sg)))
if (is_pci_p2pdma_page(sg_page(iod->sg)))
pci_p2pdma_unmap_sg(dev->dev, iod->sg, iod->nents,
rq_dma_dir(req));
else
dma_unmap_sg(dev->dev, iod->sg, iod->nents, rq_dma_dir(req));
@ -832,8 +834,8 @@ static blk_status_t nvme_map_data(struct nvme_dev *dev, struct request *req,
goto out;
if (is_pci_p2pdma_page(sg_page(iod->sg)))
nr_mapped = pci_p2pdma_map_sg(dev->dev, iod->sg, iod->nents,
rq_dma_dir(req));
nr_mapped = pci_p2pdma_map_sg_attrs(dev->dev, iod->sg,
iod->nents, rq_dma_dir(req), DMA_ATTR_NO_WARN);
else
nr_mapped = dma_map_sg_attrs(dev->dev, iod->sg, iod->nents,
rq_dma_dir(req), DMA_ATTR_NO_WARN);

View File

@ -18,13 +18,32 @@
#include <linux/percpu-refcount.h>
#include <linux/random.h>
#include <linux/seq_buf.h>
#include <linux/iommu.h>
#include <linux/xarray.h>
enum pci_p2pdma_map_type {
PCI_P2PDMA_MAP_UNKNOWN = 0,
PCI_P2PDMA_MAP_NOT_SUPPORTED,
PCI_P2PDMA_MAP_BUS_ADDR,
PCI_P2PDMA_MAP_THRU_HOST_BRIDGE,
};
struct pci_p2pdma {
struct gen_pool *pool;
bool p2pmem_published;
struct xarray map_types;
};
struct pci_p2pdma_pagemap {
struct dev_pagemap pgmap;
struct pci_dev *provider;
u64 bus_offset;
};
static struct pci_p2pdma_pagemap *to_p2p_pgmap(struct dev_pagemap *pgmap)
{
return container_of(pgmap, struct pci_p2pdma_pagemap, pgmap);
}
static ssize_t size_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
@ -87,6 +106,7 @@ static void pci_p2pdma_release(void *data)
gen_pool_destroy(p2pdma->pool);
sysfs_remove_group(&pdev->dev.kobj, &p2pmem_group);
xa_destroy(&p2pdma->map_types);
}
static int pci_p2pdma_setup(struct pci_dev *pdev)
@ -98,6 +118,8 @@ static int pci_p2pdma_setup(struct pci_dev *pdev)
if (!p2p)
return -ENOMEM;
xa_init(&p2p->map_types);
p2p->pool = gen_pool_create(PAGE_SHIFT, dev_to_node(&pdev->dev));
if (!p2p->pool)
goto out;
@ -135,6 +157,7 @@ static int pci_p2pdma_setup(struct pci_dev *pdev)
int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar, size_t size,
u64 offset)
{
struct pci_p2pdma_pagemap *p2p_pgmap;
struct dev_pagemap *pgmap;
void *addr;
int error;
@ -157,14 +180,18 @@ int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar, size_t size,
return error;
}
pgmap = devm_kzalloc(&pdev->dev, sizeof(*pgmap), GFP_KERNEL);
if (!pgmap)
p2p_pgmap = devm_kzalloc(&pdev->dev, sizeof(*p2p_pgmap), GFP_KERNEL);
if (!p2p_pgmap)
return -ENOMEM;
pgmap = &p2p_pgmap->pgmap;
pgmap->res.start = pci_resource_start(pdev, bar) + offset;
pgmap->res.end = pgmap->res.start + size - 1;
pgmap->res.flags = pci_resource_flags(pdev, bar);
pgmap->type = MEMORY_DEVICE_PCI_P2PDMA;
pgmap->pci_p2pdma_bus_offset = pci_bus_address(pdev, bar) -
p2p_pgmap->provider = pdev;
p2p_pgmap->bus_offset = pci_bus_address(pdev, bar) -
pci_resource_start(pdev, bar);
addr = devm_memremap_pages(&pdev->dev, pgmap);
@ -246,18 +273,31 @@ static void seq_buf_print_bus_devfn(struct seq_buf *buf, struct pci_dev *pdev)
seq_buf_printf(buf, "%s;", pci_name(pdev));
}
/*
* If we can't find a common upstream bridge take a look at the root
* complex and compare it to a whitelist of known good hardware.
*/
static bool root_complex_whitelist(struct pci_dev *dev)
{
struct pci_host_bridge *host = pci_find_host_bridge(dev->bus);
struct pci_dev *root = pci_get_slot(host->bus, PCI_DEVFN(0, 0));
unsigned short vendor, device;
static const struct pci_p2pdma_whitelist_entry {
unsigned short vendor;
unsigned short device;
enum {
REQ_SAME_HOST_BRIDGE = 1 << 0,
} flags;
} pci_p2pdma_whitelist[] = {
/* AMD ZEN */
{PCI_VENDOR_ID_AMD, 0x1450, 0},
if (iommu_present(dev->dev.bus))
return false;
/* Intel Xeon E5/Core i7 */
{PCI_VENDOR_ID_INTEL, 0x3c00, REQ_SAME_HOST_BRIDGE},
{PCI_VENDOR_ID_INTEL, 0x3c01, REQ_SAME_HOST_BRIDGE},
/* Intel Xeon E7 v3/Xeon E5 v3/Core i7 */
{PCI_VENDOR_ID_INTEL, 0x2f00, REQ_SAME_HOST_BRIDGE},
{PCI_VENDOR_ID_INTEL, 0x2f01, REQ_SAME_HOST_BRIDGE},
{}
};
static bool __host_bridge_whitelist(struct pci_host_bridge *host,
bool same_host_bridge)
{
struct pci_dev *root = pci_get_slot(host->bus, PCI_DEVFN(0, 0));
const struct pci_p2pdma_whitelist_entry *entry;
unsigned short vendor, device;
if (!root)
return false;
@ -266,65 +306,49 @@ static bool root_complex_whitelist(struct pci_dev *dev)
device = root->device;
pci_dev_put(root);
/* AMD ZEN host bridges can do peer to peer */
if (vendor == PCI_VENDOR_ID_AMD && device == 0x1450)
for (entry = pci_p2pdma_whitelist; entry->vendor; entry++) {
if (vendor != entry->vendor || device != entry->device)
continue;
if (entry->flags & REQ_SAME_HOST_BRIDGE && !same_host_bridge)
return false;
return true;
}
return false;
}
/*
* Find the distance through the nearest common upstream bridge between
* two PCI devices.
*
* If the two devices are the same device then 0 will be returned.
*
* If there are two virtual functions of the same device behind the same
* bridge port then 2 will be returned (one step down to the PCIe switch,
* then one step back to the same device).
*
* In the case where two devices are connected to the same PCIe switch, the
* value 4 will be returned. This corresponds to the following PCI tree:
*
* -+ Root Port
* \+ Switch Upstream Port
* +-+ Switch Downstream Port
* + \- Device A
* \-+ Switch Downstream Port
* \- Device B
*
* The distance is 4 because we traverse from Device A through the downstream
* port of the switch, to the common upstream port, back up to the second
* downstream port and then to Device B.
*
* Any two devices that don't have a common upstream bridge will return -1.
* In this way devices on separate PCIe root ports will be rejected, which
* is what we want for peer-to-peer seeing each PCIe root port defines a
* separate hierarchy domain and there's no way to determine whether the root
* complex supports forwarding between them.
*
* In the case where two devices are connected to different PCIe switches,
* this function will still return a positive distance as long as both
* switches eventually have a common upstream bridge. Note this covers
* the case of using multiple PCIe switches to achieve a desired level of
* fan-out from a root port. The exact distance will be a function of the
* number of switches between Device A and Device B.
*
* If a bridge which has any ACS redirection bits set is in the path
* then this functions will return -2. This is so we reject any
* cases where the TLPs are forwarded up into the root complex.
* In this case, a list of all infringing bridge addresses will be
* populated in acs_list (assuming it's non-null) for printk purposes.
* If we can't find a common upstream bridge take a look at the root
* complex and compare it to a whitelist of known good hardware.
*/
static int upstream_bridge_distance(struct pci_dev *provider,
struct pci_dev *client,
struct seq_buf *acs_list)
static bool host_bridge_whitelist(struct pci_dev *a, struct pci_dev *b)
{
struct pci_host_bridge *host_a = pci_find_host_bridge(a->bus);
struct pci_host_bridge *host_b = pci_find_host_bridge(b->bus);
if (host_a == host_b)
return __host_bridge_whitelist(host_a, true);
if (__host_bridge_whitelist(host_a, false) &&
__host_bridge_whitelist(host_b, false))
return true;
return false;
}
static enum pci_p2pdma_map_type
__upstream_bridge_distance(struct pci_dev *provider, struct pci_dev *client,
int *dist, bool *acs_redirects, struct seq_buf *acs_list)
{
struct pci_dev *a = provider, *b = client, *bb;
int dist_a = 0;
int dist_b = 0;
int acs_cnt = 0;
if (acs_redirects)
*acs_redirects = false;
/*
* Note, we don't need to take references to devices returned by
* pci_upstream_bridge() seeing we hold a reference to a child
@ -353,15 +377,10 @@ static int upstream_bridge_distance(struct pci_dev *provider,
dist_a++;
}
/*
* Allow the connection if both devices are on a whitelisted root
* complex, but add an arbitrary large value to the distance.
*/
if (root_complex_whitelist(provider) &&
root_complex_whitelist(client))
return 0x1000 + dist_a + dist_b;
if (dist)
*dist = dist_a + dist_b;
return -1;
return PCI_P2PDMA_MAP_THRU_HOST_BRIDGE;
check_b_path_acs:
bb = b;
@ -378,33 +397,110 @@ static int upstream_bridge_distance(struct pci_dev *provider,
bb = pci_upstream_bridge(bb);
}
if (acs_cnt)
return -2;
if (dist)
*dist = dist_a + dist_b;
return dist_a + dist_b;
if (acs_cnt) {
if (acs_redirects)
*acs_redirects = true;
return PCI_P2PDMA_MAP_THRU_HOST_BRIDGE;
}
return PCI_P2PDMA_MAP_BUS_ADDR;
}
static int upstream_bridge_distance_warn(struct pci_dev *provider,
struct pci_dev *client)
static unsigned long map_types_idx(struct pci_dev *client)
{
return (pci_domain_nr(client->bus) << 16) |
(client->bus->number << 8) | client->devfn;
}
/*
* Find the distance through the nearest common upstream bridge between
* two PCI devices.
*
* If the two devices are the same device then 0 will be returned.
*
* If there are two virtual functions of the same device behind the same
* bridge port then 2 will be returned (one step down to the PCIe switch,
* then one step back to the same device).
*
* In the case where two devices are connected to the same PCIe switch, the
* value 4 will be returned. This corresponds to the following PCI tree:
*
* -+ Root Port
* \+ Switch Upstream Port
* +-+ Switch Downstream Port
* + \- Device A
* \-+ Switch Downstream Port
* \- Device B
*
* The distance is 4 because we traverse from Device A through the downstream
* port of the switch, to the common upstream port, back up to the second
* downstream port and then to Device B.
*
* Any two devices that cannot communicate using p2pdma will return
* PCI_P2PDMA_MAP_NOT_SUPPORTED.
*
* Any two devices that have a data path that goes through the host bridge
* will consult a whitelist. If the host bridges are on the whitelist,
* this function will return PCI_P2PDMA_MAP_THRU_HOST_BRIDGE.
*
* If either bridge is not on the whitelist this function returns
* PCI_P2PDMA_MAP_NOT_SUPPORTED.
*
* If a bridge which has any ACS redirection bits set is in the path,
* acs_redirects will be set to true. In this case, a list of all infringing
* bridge addresses will be populated in acs_list (assuming it's non-null)
* for printk purposes.
*/
static enum pci_p2pdma_map_type
upstream_bridge_distance(struct pci_dev *provider, struct pci_dev *client,
int *dist, bool *acs_redirects, struct seq_buf *acs_list)
{
enum pci_p2pdma_map_type map_type;
map_type = __upstream_bridge_distance(provider, client, dist,
acs_redirects, acs_list);
if (map_type == PCI_P2PDMA_MAP_THRU_HOST_BRIDGE) {
if (!host_bridge_whitelist(provider, client))
map_type = PCI_P2PDMA_MAP_NOT_SUPPORTED;
}
if (provider->p2pdma)
xa_store(&provider->p2pdma->map_types, map_types_idx(client),
xa_mk_value(map_type), GFP_KERNEL);
return map_type;
}
static enum pci_p2pdma_map_type
upstream_bridge_distance_warn(struct pci_dev *provider, struct pci_dev *client,
int *dist)
{
struct seq_buf acs_list;
bool acs_redirects;
int ret;
seq_buf_init(&acs_list, kmalloc(PAGE_SIZE, GFP_KERNEL), PAGE_SIZE);
if (!acs_list.buffer)
return -ENOMEM;
ret = upstream_bridge_distance(provider, client, &acs_list);
if (ret == -2) {
pci_warn(client, "cannot be used for peer-to-peer DMA as ACS redirect is set between the client and provider (%s)\n",
ret = upstream_bridge_distance(provider, client, dist, &acs_redirects,
&acs_list);
if (acs_redirects) {
pci_warn(client, "ACS redirect is set between the client and provider (%s)\n",
pci_name(provider));
/* Drop final semicolon */
acs_list.buffer[acs_list.len-1] = 0;
pci_warn(client, "to disable ACS redirect for this path, add the kernel parameter: pci=disable_acs_redir=%s\n",
acs_list.buffer);
}
} else if (ret < 0) {
pci_warn(client, "cannot be used for peer-to-peer DMA as the client and provider (%s) do not share an upstream bridge\n",
if (ret == PCI_P2PDMA_MAP_NOT_SUPPORTED) {
pci_warn(client, "cannot be used for peer-to-peer DMA as the client and provider (%s) do not share an upstream bridge or whitelisted host bridge\n",
pci_name(provider));
}
@ -421,22 +517,22 @@ static int upstream_bridge_distance_warn(struct pci_dev *provider,
* @num_clients: number of clients in the array
* @verbose: if true, print warnings for devices when we return -1
*
* Returns -1 if any of the clients are not compatible (behind the same
* root port as the provider), otherwise returns a positive number where
* a lower number is the preferable choice. (If there's one client
* that's the same as the provider it will return 0, which is best choice).
* Returns -1 if any of the clients are not compatible, otherwise returns a
* positive number where a lower number is the preferable choice. (If there's
* one client that's the same as the provider it will return 0, which is best
* choice).
*
* For now, "compatible" means the provider and the clients are all behind
* the same PCI root port. This cuts out cases that may work but is safest
* for the user. Future work can expand this to white-list root complexes that
* can safely forward between each ports.
* "compatible" means the provider and the clients are either all behind
* the same PCI root port or the host bridges connected to each of the devices
* are listed in the 'pci_p2pdma_whitelist'.
*/
int pci_p2pdma_distance_many(struct pci_dev *provider, struct device **clients,
int num_clients, bool verbose)
{
bool not_supported = false;
struct pci_dev *pci_client;
int distance = 0;
int total_dist = 0;
int distance;
int i, ret;
if (num_clients == 0)
@ -461,26 +557,26 @@ int pci_p2pdma_distance_many(struct pci_dev *provider, struct device **clients,
if (verbose)
ret = upstream_bridge_distance_warn(provider,
pci_client);
pci_client, &distance);
else
ret = upstream_bridge_distance(provider, pci_client,
NULL);
&distance, NULL, NULL);
pci_dev_put(pci_client);
if (ret < 0)
if (ret == PCI_P2PDMA_MAP_NOT_SUPPORTED)
not_supported = true;
if (not_supported && !verbose)
break;
distance += ret;
total_dist += distance;
}
if (not_supported)
return -1;
return distance;
return total_dist;
}
EXPORT_SYMBOL_GPL(pci_p2pdma_distance_many);
@ -706,21 +802,19 @@ void pci_p2pmem_publish(struct pci_dev *pdev, bool publish)
}
EXPORT_SYMBOL_GPL(pci_p2pmem_publish);
/**
* pci_p2pdma_map_sg - map a PCI peer-to-peer scatterlist for DMA
* @dev: device doing the DMA request
* @sg: scatter list to map
* @nents: elements in the scatterlist
* @dir: DMA direction
*
* Scatterlists mapped with this function should not be unmapped in any way.
*
* Returns the number of SG entries mapped or 0 on error.
*/
int pci_p2pdma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
enum dma_data_direction dir)
static enum pci_p2pdma_map_type pci_p2pdma_map_type(struct pci_dev *provider,
struct pci_dev *client)
{
if (!provider->p2pdma)
return PCI_P2PDMA_MAP_NOT_SUPPORTED;
return xa_to_value(xa_load(&provider->p2pdma->map_types,
map_types_idx(client)));
}
static int __pci_p2pdma_map_sg(struct pci_p2pdma_pagemap *p2p_pgmap,
struct device *dev, struct scatterlist *sg, int nents)
{
struct dev_pagemap *pgmap;
struct scatterlist *s;
phys_addr_t paddr;
int i;
@ -736,16 +830,80 @@ int pci_p2pdma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
return 0;
for_each_sg(sg, s, nents, i) {
pgmap = sg_page(s)->pgmap;
paddr = sg_phys(s);
s->dma_address = paddr - pgmap->pci_p2pdma_bus_offset;
s->dma_address = paddr - p2p_pgmap->bus_offset;
sg_dma_len(s) = s->length;
}
return nents;
}
EXPORT_SYMBOL_GPL(pci_p2pdma_map_sg);
/**
* pci_p2pdma_map_sg - map a PCI peer-to-peer scatterlist for DMA
* @dev: device doing the DMA request
* @sg: scatter list to map
* @nents: elements in the scatterlist
* @dir: DMA direction
* @attrs: DMA attributes passed to dma_map_sg() (if called)
*
* Scatterlists mapped with this function should be unmapped using
* pci_p2pdma_unmap_sg_attrs().
*
* Returns the number of SG entries mapped or 0 on error.
*/
int pci_p2pdma_map_sg_attrs(struct device *dev, struct scatterlist *sg,
int nents, enum dma_data_direction dir, unsigned long attrs)
{
struct pci_p2pdma_pagemap *p2p_pgmap =
to_p2p_pgmap(sg_page(sg)->pgmap);
struct pci_dev *client;
if (WARN_ON_ONCE(!dev_is_pci(dev)))
return 0;
client = to_pci_dev(dev);
switch (pci_p2pdma_map_type(p2p_pgmap->provider, client)) {
case PCI_P2PDMA_MAP_THRU_HOST_BRIDGE:
return dma_map_sg_attrs(dev, sg, nents, dir, attrs);
case PCI_P2PDMA_MAP_BUS_ADDR:
return __pci_p2pdma_map_sg(p2p_pgmap, dev, sg, nents);
default:
WARN_ON_ONCE(1);
return 0;
}
}
EXPORT_SYMBOL_GPL(pci_p2pdma_map_sg_attrs);
/**
* pci_p2pdma_unmap_sg - unmap a PCI peer-to-peer scatterlist that was
* mapped with pci_p2pdma_map_sg()
* @dev: device doing the DMA request
* @sg: scatter list to map
* @nents: number of elements returned by pci_p2pdma_map_sg()
* @dir: DMA direction
* @attrs: DMA attributes passed to dma_unmap_sg() (if called)
*/
void pci_p2pdma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg,
int nents, enum dma_data_direction dir, unsigned long attrs)
{
struct pci_p2pdma_pagemap *p2p_pgmap =
to_p2p_pgmap(sg_page(sg)->pgmap);
enum pci_p2pdma_map_type map_type;
struct pci_dev *client;
if (WARN_ON_ONCE(!dev_is_pci(dev)))
return;
client = to_pci_dev(dev);
map_type = pci_p2pdma_map_type(p2p_pgmap->provider, client);
if (map_type == PCI_P2PDMA_MAP_THRU_HOST_BRIDGE)
dma_unmap_sg_attrs(dev, sg, nents, dir, attrs);
}
EXPORT_SYMBOL_GPL(pci_p2pdma_unmap_sg_attrs);
/**
* pci_p2pdma_enable_store - parse a configfs/sysfs attribute store

View File

@ -112,7 +112,6 @@ struct dev_pagemap {
struct device *dev;
enum memory_type type;
unsigned int flags;
u64 pci_p2pdma_bus_offset;
const struct dev_pagemap_ops *ops;
};

View File

@ -30,8 +30,10 @@ struct scatterlist *pci_p2pmem_alloc_sgl(struct pci_dev *pdev,
unsigned int *nents, u32 length);
void pci_p2pmem_free_sgl(struct pci_dev *pdev, struct scatterlist *sgl);
void pci_p2pmem_publish(struct pci_dev *pdev, bool publish);
int pci_p2pdma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
enum dma_data_direction dir);
int pci_p2pdma_map_sg_attrs(struct device *dev, struct scatterlist *sg,
int nents, enum dma_data_direction dir, unsigned long attrs);
void pci_p2pdma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg,
int nents, enum dma_data_direction dir, unsigned long attrs);
int pci_p2pdma_enable_store(const char *page, struct pci_dev **p2p_dev,
bool *use_p2pdma);
ssize_t pci_p2pdma_enable_show(char *page, struct pci_dev *p2p_dev,
@ -81,11 +83,17 @@ static inline void pci_p2pmem_free_sgl(struct pci_dev *pdev,
static inline void pci_p2pmem_publish(struct pci_dev *pdev, bool publish)
{
}
static inline int pci_p2pdma_map_sg(struct device *dev,
struct scatterlist *sg, int nents, enum dma_data_direction dir)
static inline int pci_p2pdma_map_sg_attrs(struct device *dev,
struct scatterlist *sg, int nents, enum dma_data_direction dir,
unsigned long attrs)
{
return 0;
}
static inline void pci_p2pdma_unmap_sg_attrs(struct device *dev,
struct scatterlist *sg, int nents, enum dma_data_direction dir,
unsigned long attrs)
{
}
static inline int pci_p2pdma_enable_store(const char *page,
struct pci_dev **p2p_dev, bool *use_p2pdma)
{
@ -111,4 +119,16 @@ static inline struct pci_dev *pci_p2pmem_find(struct device *client)
return pci_p2pmem_find_many(&client, 1);
}
static inline int pci_p2pdma_map_sg(struct device *dev, struct scatterlist *sg,
int nents, enum dma_data_direction dir)
{
return pci_p2pdma_map_sg_attrs(dev, sg, nents, dir, 0);
}
static inline void pci_p2pdma_unmap_sg(struct device *dev,
struct scatterlist *sg, int nents, enum dma_data_direction dir)
{
pci_p2pdma_unmap_sg_attrs(dev, sg, nents, dir, 0);
}
#endif /* _LINUX_PCI_P2P_H */