From: Björn Töpel <bjorn.topel@xxxxxxxxx>
In order to simplify AF_XDP zero-copy enablement for NIC driver
developers, a new AF_XDP buffer allocation API is added. The
implementation is based on a single core (single producer/consumer)
buffer pool for the AF_XDP UMEM.
A buffer is allocated using the xsk_buff_alloc() function, and
returned using xsk_buff_free(). If a buffer is disassociated with the
pool, e.g. when a buffer is passed to an AF_XDP socket, a buffer is
said to be released. Currently, the release function is only used by
the AF_XDP internals and not visible to the driver.
Drivers using this API should register the XDP memory model with the
new MEM_TYPE_XSK_BUFF_POOL type.
The API is defined in net/xdp_sock_drv.h.
The buffer type is struct xdp_buff, and follows the lifetime of
regular xdp_buffs, i.e. the lifetime of an xdp_buff is restricted to
a NAPI context. In other words, the API is not replacing xdp_frames.
In addition to introducing the API and implementations, the AF_XDP
core is migrated to use the new APIs.
Signed-off-by: Björn Töpel <bjorn.topel@xxxxxxxxx>
---
include/net/xdp.h | 4 +-
include/net/xdp_sock.h | 2 +
include/net/xdp_sock_drv.h | 132 +++++++++++
include/net/xsk_buff_pool.h | 54 +++++
include/trace/events/xdp.h | 3 +-
net/core/xdp.c | 14 +-
net/xdp/Makefile | 1 +
net/xdp/xdp_umem.c | 19 +-
net/xdp/xsk.c | 147 +++++-------
net/xdp/xsk_buff_pool.c | 451 ++++++++++++++++++++++++++++++++++++
net/xdp/xsk_diag.c | 2 +-
net/xdp/xsk_queue.h | 59 +++--
12 files changed, 769 insertions(+), 119 deletions(-)
create mode 100644 include/net/xsk_buff_pool.h
create mode 100644 net/xdp/xsk_buff_pool.c
diff --git a/include/net/xdp.h b/include/net/xdp.h
index 3cc6d5d84aa4..83173e4d306c 100644
--- a/include/net/xdp.h
+++ b/include/net/xdp.h
@@ -38,6 +38,7 @@ enum xdp_mem_type {
MEM_TYPE_PAGE_ORDER0, /* Orig XDP full page model */
MEM_TYPE_PAGE_POOL,
MEM_TYPE_ZERO_COPY,
+ MEM_TYPE_XSK_BUFF_POOL,
MEM_TYPE_MAX,
};
@@ -101,7 +102,8 @@ struct xdp_frame *convert_to_xdp_frame(struct xdp_buff *xdp)
int metasize;
int headroom;
- if (xdp->rxq->mem.type == MEM_TYPE_ZERO_COPY)
+ if (xdp->rxq->mem.type == MEM_TYPE_ZERO_COPY ||
+ xdp->rxq->mem.type == MEM_TYPE_XSK_BUFF_POOL)
return xdp_convert_zc_to_xdp_frame(xdp);
/* Assure headroom is available for storing info */
diff --git a/include/net/xdp_sock.h b/include/net/xdp_sock.h
index 425a42c54b95..117cc1e2ca38 100644
--- a/include/net/xdp_sock.h
+++ b/include/net/xdp_sock.h
@@ -31,11 +31,13 @@ struct xdp_umem_fq_reuse {
struct xdp_umem {
struct xsk_queue *fq;
struct xsk_queue *cq;
+ struct xsk_buff_pool *pool;
struct xdp_umem_page *pages;
u64 chunk_mask;
u64 size;
u32 headroom;
u32 chunk_size_nohr;
+ u32 chunk_size;
struct user_struct *user;
unsigned long address;
refcount_t users;
diff --git a/include/net/xdp_sock_drv.h b/include/net/xdp_sock_drv.h
index 98dd6962e6d4..232f2e3f01ac 100644
--- a/include/net/xdp_sock_drv.h
+++ b/include/net/xdp_sock_drv.h
@@ -7,6 +7,7 @@
#define _LINUX_XDP_SOCK_DRV_H
#include <net/xdp_sock.h>
+#include <net/xsk_buff_pool.h>
#ifdef CONFIG_XDP_SOCKETS
@@ -96,6 +97,77 @@ static inline u64 xsk_umem_adjust_offset(struct xdp_umem *umem, u64 address,
return address + offset;
}
+static inline u32 xsk_umem_get_rx_frame_size(struct xdp_umem *umem)
+{
+ return umem->chunk_size - umem->headroom - XDP_PACKET_HEADROOM;
+}
+
+static inline void xsk_buff_set_rxq_info(struct xdp_umem *umem,
+ struct xdp_rxq_info *rxq)
+{
+ xp_set_rxq_info(umem->pool, rxq);
+}
+
+static inline void xsk_buff_dma_unmap(struct xdp_umem *umem,
+ unsigned long attrs)
+{
+ xp_dma_unmap(umem->pool, attrs);
+}
+
+static inline int xsk_buff_dma_map(struct xdp_umem *umem, struct device *dev,
+ unsigned long attrs)
+{
+ return xp_dma_map(umem->pool, dev, attrs, umem->pgs, umem->npgs);
+}
+
+static inline dma_addr_t xsk_buff_xdp_get_dma(struct xdp_buff *xdp)
+{
+ struct xdp_buff_xsk *xskb = container_of(xdp, struct xdp_buff_xsk, xdp);
+
+ return xp_get_dma(xskb);
+}
+
+static inline struct xdp_buff *xsk_buff_alloc(struct xdp_umem *umem)
+{
+ return xp_alloc(umem->pool);
+}
+
+static inline bool xsk_buff_can_alloc(struct xdp_umem *umem, u32 count)
+{
+ return xp_can_alloc(umem->pool, count);
+}
+
+static inline void xsk_buff_free(struct xdp_buff *xdp)
+{
+ struct xdp_buff_xsk *xskb = container_of(xdp, struct xdp_buff_xsk, xdp);
+
+ xp_free(xskb);
+}
+
+static inline dma_addr_t xsk_buff_raw_get_dma(struct xdp_umem *umem, u64 addr)
+{
+ return xp_raw_get_dma(umem->pool, addr);
+}
+
+static inline void *xsk_buff_raw_get_data(struct xdp_umem *umem, u64 addr)
+{
+ return xp_raw_get_data(umem->pool, addr);
+}
+
+static inline void xsk_buff_dma_sync_for_cpu(struct xdp_buff *xdp)
+{
+ struct xdp_buff_xsk *xskb = container_of(xdp, struct xdp_buff_xsk, xdp);
+
+ xp_dma_sync_for_cpu(xskb);
+}
+
+static inline void xsk_buff_raw_dma_sync_for_device(struct xdp_umem *umem,
+ dma_addr_t dma,
+ size_t size)
+{
+ xp_dma_sync_for_device(umem->pool, dma, size);
+}
+
#else
static inline bool xsk_umem_has_addrs(struct xdp_umem *umem, u32 cnt)
@@ -202,6 +274,66 @@ static inline u64 xsk_umem_adjust_offset(struct xdp_umem *umem, u64 handle,
return 0;
}
+static inline u32 xsk_umem_get_rx_frame_size(struct xdp_umem *umem)
+{
+ return 0;
+}
+
+static inline void xsk_buff_set_rxq_info(struct xdp_umem *umem,
+ struct xdp_rxq_info *rxq)
+{
+}
+
+static inline void xsk_buff_dma_unmap(struct xdp_umem *umem,
+ unsigned long attrs)
+{
+}
+
+static inline int xsk_buff_dma_map(struct xdp_umem *umem, struct device *dev,
+ unsigned long attrs)
+{
+ return 0;
+}
+
+static inline dma_addr_t xsk_buff_xdp_get_dma(struct xdp_buff *xdp)
+{
+ return 0;
+}
+
+static inline struct xdp_buff *xsk_buff_alloc(struct xdp_umem *umem)
+{
+ return NULL;
+}
+
+static inline bool xsk_buff_can_alloc(struct xdp_umem *umem, u32 count)
+{
+ return false;
+}
+
+static inline void xsk_buff_free(struct xdp_buff *xdp)
+{
+}
+
+static inline dma_addr_t xsk_buff_raw_get_dma(struct xdp_umem *umem, u64 addr)
+{
+ return 0;
+}
+
+static inline void *xsk_buff_raw_get_data(struct xdp_umem *umem, u64 addr)
+{
+ return NULL;
+}
+
+static inline void xsk_buff_dma_sync_for_cpu(struct xdp_buff *xdp)
+{
+}
+
+static inline void xsk_buff_raw_dma_sync_for_device(struct xdp_umem *umem,
+ dma_addr_t dma,
+ size_t size)
+{
+}
+
#endif /* CONFIG_XDP_SOCKETS */
#endif /* _LINUX_XDP_SOCK_DRV_H */
diff --git a/include/net/xsk_buff_pool.h b/include/net/xsk_buff_pool.h
new file mode 100644
index 000000000000..9abef166441d
--- /dev/null
+++ b/include/net/xsk_buff_pool.h
@@ -0,0 +1,54 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright(c) 2020 Intel Corporation. */
+
+#ifndef XSK_BUFF_POOL_H_
+#define XSK_BUFF_POOL_H_
+
+#include <linux/types.h>
+#include <linux/dma-mapping.h>
+#include <net/xdp.h>
+
+struct xsk_buff_pool;
+struct xdp_rxq_info;
+struct xsk_queue;
+struct xdp_desc;
+struct device;
+struct page;
+
+struct xdp_buff_xsk {
+ struct xdp_buff xdp;
+ dma_addr_t dma;
+ struct xsk_buff_pool *pool;
+ bool unaligned;
+ u64 orig_addr;
+ struct list_head free_list_node;
+};
+
+/* AF_XDP core. */
+struct xsk_buff_pool *xp_create(struct page **pages, u32 nr_pages, u32 chunks,
+ u32 chunk_size, u32 headroom, u64 size,
+ bool unaligned);
+void xp_set_fq(struct xsk_buff_pool *pool, struct xsk_queue *fq);
+void xp_destroy(struct xsk_buff_pool *pool);
+void xp_release(struct xdp_buff_xsk *xskb);
+u64 xp_get_handle(struct xdp_buff_xsk *xskb);
+bool xp_validate_desc(struct xsk_buff_pool *pool, struct xdp_desc *desc);
+
+/* AF_XDP, and XDP core. */
+void xp_free(struct xdp_buff_xsk *xskb);
+
+/* AF_XDP ZC drivers, via xdp_sock_buff.h */
+void xp_set_rxq_info(struct xsk_buff_pool *pool, struct xdp_rxq_info *rxq);
+int xp_dma_map(struct xsk_buff_pool *pool, struct device *dev,
+ unsigned long attrs, struct page **pages, u32 nr_pages);
+void xp_dma_unmap(struct xsk_buff_pool *pool, unsigned long attrs);
+struct xdp_buff *xp_alloc(struct xsk_buff_pool *pool);
+bool xp_can_alloc(struct xsk_buff_pool *pool, u32 count);
+void *xp_raw_get_data(struct xsk_buff_pool *pool, u64 addr);
+dma_addr_t xp_raw_get_dma(struct xsk_buff_pool *pool, u64 addr);
+dma_addr_t xp_get_dma(struct xdp_buff_xsk *xskb);
+void xp_dma_sync_for_cpu(struct xdp_buff_xsk *xskb);
+void xp_dma_sync_for_device(struct xsk_buff_pool *pool, dma_addr_t dma,
+ size_t size);
+
+#endif /* XSK_BUFF_POOL_H_ */
diff --git a/include/trace/events/xdp.h b/include/trace/events/xdp.h
index b95d65e8c628..48547a12fa27 100644
--- a/include/trace/events/xdp.h
+++ b/include/trace/events/xdp.h
@@ -287,7 +287,8 @@ TRACE_EVENT(xdp_devmap_xmit,
FN(PAGE_SHARED) \
FN(PAGE_ORDER0) \
FN(PAGE_POOL) \
- FN(ZERO_COPY)
+ FN(ZERO_COPY) \
+ FN(XSK_BUFF_POOL)
#define __MEM_TYPE_TP_FN(x) \
TRACE_DEFINE_ENUM(MEM_TYPE_##x);
diff --git a/net/core/xdp.c b/net/core/xdp.c
index 4c7ea85486af..89053ef8333b 100644
--- a/net/core/xdp.c
+++ b/net/core/xdp.c
@@ -16,6 +16,7 @@
#include <net/xdp.h>
#include <net/xdp_priv.h> /* struct xdp_mem_allocator */
#include <trace/events/xdp.h>
+#include <net/xdp_sock_drv.h>
#define REG_STATE_NEW 0x0
#define REG_STATE_REGISTERED 0x1
@@ -360,7 +361,7 @@ EXPORT_SYMBOL_GPL(xdp_rxq_info_reg_mem_model);
* of xdp_frames/pages in those cases.
*/
static void __xdp_return(void *data, struct xdp_mem_info *mem, bool napi_direct,
- unsigned long handle)
+ unsigned long handle, struct xdp_buff *xdp)
{
struct xdp_mem_allocator *xa;
struct page *page;
@@ -389,6 +390,11 @@ static void __xdp_return(void *data, struct xdp_mem_info *mem, bool napi_direct,
xa = rhashtable_lookup(mem_id_ht, &mem->id, mem_id_rht_params);
xa->zc_alloc->free(xa->zc_alloc, handle);
rcu_read_unlock();
+ break;
+ case MEM_TYPE_XSK_BUFF_POOL:
+ /* NB! Only valid from an xdp_buff! */
+ xsk_buff_free(xdp);
+ break;
default:
/* Not possible, checked in xdp_rxq_info_reg_mem_model() */
break;
@@ -397,19 +403,19 @@ static void __xdp_return(void *data, struct xdp_mem_info *mem, bool napi_direct,
void xdp_return_frame(struct xdp_frame *xdpf)
{
- __xdp_return(xdpf->data, &xdpf->mem, false, 0);
+ __xdp_return(xdpf->data, &xdpf->mem, false, 0, NULL);
}
EXPORT_SYMBOL_GPL(xdp_return_frame);
void xdp_return_frame_rx_napi(struct xdp_frame *xdpf)
{
- __xdp_return(xdpf->data, &xdpf->mem, true, 0);
+ __xdp_return(xdpf->data, &xdpf->mem, true, 0, NULL);
}
EXPORT_SYMBOL_GPL(xdp_return_frame_rx_napi);
void xdp_return_buff(struct xdp_buff *xdp)
{
- __xdp_return(xdp->data, &xdp->rxq->mem, true, xdp->handle);
+ __xdp_return(xdp->data, &xdp->rxq->mem, true, xdp->handle, xdp);
}
EXPORT_SYMBOL_GPL(xdp_return_buff);
diff --git a/net/xdp/Makefile b/net/xdp/Makefile
index 90b5460d6166..30cdc4315f42 100644
--- a/net/xdp/Makefile
+++ b/net/xdp/Makefile
@@ -1,3 +1,4 @@
# SPDX-License-Identifier: GPL-2.0-only
obj-$(CONFIG_XDP_SOCKETS) += xsk.o xdp_umem.o xsk_queue.o xskmap.o
+obj-$(CONFIG_XDP_SOCKETS) += xsk_buff_pool.o
obj-$(CONFIG_XDP_SOCKETS_DIAG) += xsk_diag.o
diff --git a/net/xdp/xdp_umem.c b/net/xdp/xdp_umem.c
index ed7a6060f73c..0bc8a50d553f 100644
--- a/net/xdp/xdp_umem.c
+++ b/net/xdp/xdp_umem.c
@@ -245,7 +245,7 @@ static void xdp_umem_release(struct xdp_umem *umem)
}
xsk_reuseq_destroy(umem);
-
+ xp_destroy(umem->pool);
xdp_umem_unmap_pages(umem);
xdp_umem_unpin_pages(umem);
@@ -391,6 +391,7 @@ static int xdp_umem_reg(struct xdp_umem *umem, struct xdp_umem_reg *mr)
umem->size = size;
umem->headroom = headroom;
umem->chunk_size_nohr = chunk_size - headroom;
+ umem->chunk_size = chunk_size;
umem->npgs = size / PAGE_SIZE;
umem->pgs = NULL;
umem->user = NULL;
@@ -416,11 +417,21 @@ static int xdp_umem_reg(struct xdp_umem *umem, struct xdp_umem_reg *mr)
}
err = xdp_umem_map_pages(umem);
- if (!err)
- return 0;
+ if (err)
+ goto out_pages;
- kvfree(umem->pages);
+ umem->pool = xp_create(umem->pgs, umem->npgs, chunks, chunk_size,
+ headroom, size, unaligned_chunks);
+ if (!umem->pool) {
+ err = -ENOMEM;
+ goto out_unmap;
+ }
+ return 0;
+out_unmap:
+ xdp_umem_unmap_pages(umem);
+out_pages:
+ kvfree(umem->pages);
out_pin:
xdp_umem_unpin_pages(umem);
out_account:
diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c
index a5cf3280f88e..df36c12236c3 100644
--- a/net/xdp/xsk.c
+++ b/net/xdp/xsk.c
@@ -117,76 +117,67 @@ bool xsk_umem_uses_need_wakeup(struct xdp_umem *umem)
}
EXPORT_SYMBOL(xsk_umem_uses_need_wakeup);
-/* If a buffer crosses a page boundary, we need to do 2 memcpy's, one for
- * each page. This is only required in copy mode.
- */
-static void __xsk_rcv_memcpy(struct xdp_umem *umem, u64 addr, void *from_buf,
- u32 len, u32 metalen)
+static int __xsk_rcv_zc(struct xdp_sock *xs, struct xdp_buff *xdp, u32 len)
{
- void *to_buf = xdp_umem_get_data(umem, addr);
-
- addr = xsk_umem_add_offset_to_addr(addr);
- if (xskq_cons_crosses_non_contig_pg(umem, addr, len + metalen)) {
- void *next_pg_addr = umem->pages[(addr >> PAGE_SHIFT) + 1].addr;
- u64 page_start = addr & ~(PAGE_SIZE - 1);
- u64 first_len = PAGE_SIZE - (addr - page_start);
-
- memcpy(to_buf, from_buf, first_len);
- memcpy(next_pg_addr, from_buf + first_len,
- len + metalen - first_len);
+ struct xdp_buff_xsk *xskb = container_of(xdp, struct xdp_buff_xsk, xdp);
+ u64 addr;
+ int err;
- return;
+ addr = xp_get_handle(xskb);
+ err = xskq_prod_reserve_desc(xs->rx, addr, len);
+ if (err) {
+ xs->rx_dropped++;
+ return err;
}
- memcpy(to_buf, from_buf, len + metalen);
+ xp_release(xskb);
+ return 0;
}
-static int __xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp, u32 len)
+static void xsk_copy_xdp(struct xdp_buff *to, struct xdp_buff *from, u32 len)
{
- u64 offset = xs->umem->headroom;
- u64 addr, memcpy_addr;
- void *from_buf;
+ void *from_buf, *to_buf;
u32 metalen;
- int err;
-
- if (!xskq_cons_peek_addr(xs->umem->fq, &addr, xs->umem) ||
- len > xs->umem->chunk_size_nohr - XDP_PACKET_HEADROOM) {
- xs->rx_dropped++;
- return -ENOSPC;
- }
- if (unlikely(xdp_data_meta_unsupported(xdp))) {
- from_buf = xdp->data;
+ if (unlikely(xdp_data_meta_unsupported(from))) {
+ from_buf = from->data;
+ to_buf = to->data;
metalen = 0;
} else {
- from_buf = xdp->data_meta;
- metalen = xdp->data - xdp->data_meta;
+ from_buf = from->data_meta;
+ metalen = from->data - from->data_meta;
+ to_buf = to->data - metalen;
}
- memcpy_addr = xsk_umem_adjust_offset(xs->umem, addr, offset);
- __xsk_rcv_memcpy(xs->umem, memcpy_addr, from_buf, len, metalen);
-
- offset += metalen;
- addr = xsk_umem_adjust_offset(xs->umem, addr, offset);
- err = xskq_prod_reserve_desc(xs->rx, addr, len);
- if (!err) {
- xskq_cons_release(xs->umem->fq);
- xdp_return_buff(xdp);
- return 0;
- }
-
- xs->rx_dropped++;
- return err;
+ memcpy(to_buf, from_buf, len + metalen);
}
-static int __xsk_rcv_zc(struct xdp_sock *xs, struct xdp_buff *xdp, u32 len)
+static int __xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp, u32 len,
+ bool explicit_free)
{
- int err = xskq_prod_reserve_desc(xs->rx, xdp->handle, len);
+ struct xdp_buff *xsk_xdp;
+ int err;
- if (err)
+ if (len > xsk_umem_get_rx_frame_size(xs->umem)) {
+ xs->rx_dropped++;
+ return -ENOSPC;
+ }
+
+ xsk_xdp = xsk_buff_alloc(xs->umem);
+ if (!xsk_xdp) {
xs->rx_dropped++;
+ return -ENOSPC;
+ }
- return err;
+ xsk_copy_xdp(xsk_xdp, xdp, len);
+ err = __xsk_rcv_zc(xs, xsk_xdp, len);
+ if (err) {
+ xsk_buff_free(xsk_xdp);
+ return err;
+ }
+ if (explicit_free)
+ xdp_return_buff(xdp);
+ return 0;
}
static bool xsk_is_bound(struct xdp_sock *xs)
@@ -199,7 +190,8 @@ static bool xsk_is_bound(struct xdp_sock *xs)
return false;
}
-static int xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp)
+static int xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp,
+ bool explicit_free)
{
u32 len;
@@ -211,8 +203,10 @@ static int xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp)
len = xdp->data_end - xdp->data;
- return (xdp->rxq->mem.type == MEM_TYPE_ZERO_COPY) ?
- __xsk_rcv_zc(xs, xdp, len) : __xsk_rcv(xs, xdp, len);
+ return xdp->rxq->mem.type == MEM_TYPE_ZERO_COPY ||
+ xdp->rxq->mem.type == MEM_TYPE_XSK_BUFF_POOL ?
+ __xsk_rcv_zc(xs, xdp, len) :
+ __xsk_rcv(xs, xdp, len, explicit_free);
}
static void xsk_flush(struct xdp_sock *xs)
@@ -224,46 +218,11 @@ static void xsk_flush(struct xdp_sock *xs)
int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp)
{
- u32 metalen = xdp->data - xdp->data_meta;
- u32 len = xdp->data_end - xdp->data;
- u64 offset = xs->umem->headroom;
- void *buffer;
- u64 addr;
int err;
spin_lock_bh(&xs->rx_lock);
-
- if (xs->dev != xdp->rxq->dev || xs->queue_id != xdp->rxq->queue_index) {
- err = -EINVAL;
- goto out_unlock;
- }
-
- if (!xskq_cons_peek_addr(xs->umem->fq, &addr, xs->umem) ||
- len > xs->umem->chunk_size_nohr - XDP_PACKET_HEADROOM) {
- err = -ENOSPC;
- goto out_drop;
- }
-
- addr = xsk_umem_adjust_offset(xs->umem, addr, offset);
- buffer = xdp_umem_get_data(xs->umem, addr);
- memcpy(buffer, xdp->data_meta, len + metalen);
-
- addr = xsk_umem_adjust_offset(xs->umem, addr, metalen);
- err = xskq_prod_reserve_desc(xs->rx, addr, len);
- if (err)
- goto out_drop;
-
- xskq_cons_release(xs->umem->fq);
- xskq_prod_submit(xs->rx);
-
- spin_unlock_bh(&xs->rx_lock);
-
- xs->sk.sk_data_ready(&xs->sk);
- return 0;
-
-out_drop:
- xs->rx_dropped++;
-out_unlock:
+ err = xsk_rcv(xs, xdp, false);
+ xsk_flush(xs);
spin_unlock_bh(&xs->rx_lock);
return err;
}
@@ -273,7 +232,7 @@ int __xsk_map_redirect(struct xdp_sock *xs, struct xdp_buff *xdp)
struct list_head *flush_list = this_cpu_ptr(&xskmap_flush_list);
int err;
- err = xsk_rcv(xs, xdp);
+ err = xsk_rcv(xs, xdp, true);
if (err)
return err;
@@ -404,7 +363,7 @@ static int xsk_generic_xmit(struct sock *sk)
skb_put(skb, len);
addr = desc.addr;
- buffer = xdp_umem_get_data(xs->umem, addr);
+ buffer = xsk_buff_raw_get_data(xs->umem, addr);
err = skb_store_bits(skb, 0, buffer, len);
/* This is the backpressure mechanism for the Tx path.
* Reserve space in the completion queue and only proceed
@@ -860,6 +819,8 @@ static int xsk_setsockopt(struct socket *sock, int level, int optname,
q = (optname == XDP_UMEM_FILL_RING) ? &xs->umem->fq :
&xs->umem->cq;
err = xsk_init_queue(entries, q, true);
+ if (optname == XDP_UMEM_FILL_RING)
+ xp_set_fq(xs->umem->pool, *q);
mutex_unlock(&xs->mutex);
return err;
}
diff --git a/net/xdp/xsk_buff_pool.c b/net/xdp/xsk_buff_pool.c
new file mode 100644
index 000000000000..30cb2de77a03
--- /dev/null
+++ b/net/xdp/xsk_buff_pool.c
@@ -0,0 +1,451 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <net/xsk_buff_pool.h>
+#include <net/xdp_sock.h>
+#include <linux/dma-direct.h>
+#include <linux/dma-noncoherent.h>
+
+#include "xsk_queue.h"
+
+struct xsk_buff_pool {
+ struct xsk_queue *fq;
+ struct list_head free_list;
+ dma_addr_t *dma_pages;
+ struct xdp_buff_xsk *heads;
+ u64 chunk_mask;
+ u64 addrs_cnt;
+ u32 free_list_cnt;
+ u32 dma_pages_cnt;
+ u32 heads_cnt;
+ u32 free_heads_cnt;
+ u32 headroom;
+ u32 chunk_size;
+ u32 frame_len;
+ bool cheap_dma;
+ bool unaligned;
+ void *addrs;
+ struct device *dev;
+ struct xdp_buff_xsk *free_heads[];
+};
+
+static void xp_addr_unmap(struct xsk_buff_pool *pool)
+{
+ vunmap(pool->addrs);
+}
+
+static int xp_addr_map(struct xsk_buff_pool *pool,
+ struct page **pages, u32 nr_pages)
+{
+ pool->addrs = vmap(pages, nr_pages, VM_MAP, PAGE_KERNEL);
+ if (!pool->addrs)
+ return -ENOMEM;
+ return 0;
+}
+
+void xp_destroy(struct xsk_buff_pool *pool)
+{
+ if (!pool)
+ return;
+
+ xp_addr_unmap(pool);
+ kvfree(pool->heads);
+ kvfree(pool);
+}
+
+struct xsk_buff_pool *xp_create(struct page **pages, u32 nr_pages, u32 chunks,
+ u32 chunk_size, u32 headroom, u64 size,
+ bool unaligned)
+{
+ struct xsk_buff_pool *pool;
+ struct xdp_buff_xsk *xskb;
+ int err;
+ u32 i;
+
+ pool = kvzalloc(struct_size(pool, free_heads, chunks), GFP_KERNEL);
+ if (!pool)
+ goto out;
+
+ pool->heads = kvcalloc(chunks, sizeof(*pool->heads), GFP_KERNEL);
+ if (!pool->heads)
+ goto out;
+
+ pool->chunk_mask = ~((u64)chunk_size - 1);
+ pool->addrs_cnt = size;
+ pool->heads_cnt = chunks;
+ pool->free_heads_cnt = chunks;
+ pool->headroom = headroom;
+ pool->chunk_size = chunk_size;
+ pool->cheap_dma = true;
+ pool->unaligned = unaligned;
+ pool->frame_len = chunk_size - headroom - XDP_PACKET_HEADROOM;
+ INIT_LIST_HEAD(&pool->free_list);
+
+ for (i = 0; i < pool->free_heads_cnt; i++) {
+ xskb = &pool->heads[i];
+ xskb->pool = pool;
+ pool->free_heads[i] = xskb;
+ }
+
+ err = xp_addr_map(pool, pages, nr_pages);
+ if (!err)
+ return pool;
+
+out:
+ xp_destroy(pool);
+ return NULL;
+}
+
+void xp_set_fq(struct xsk_buff_pool *pool, struct xsk_queue *fq)
+{
+ pool->fq = fq;
+}
+
+void xp_set_rxq_info(struct xsk_buff_pool *pool, struct xdp_rxq_info *rxq)
+{
+ u32 i;
+
+ for (i = 0; i < pool->heads_cnt; i++)
+ pool->heads[i].xdp.rxq = rxq;
+}
+EXPORT_SYMBOL(xp_set_rxq_info);
+
+void xp_dma_unmap(struct xsk_buff_pool *pool, unsigned long attrs)
+{
+ dma_addr_t *dma;
+ u32 i;
+
+ if (pool->dma_pages_cnt == 0)
+ return;
+
+ for (i = 0; i < pool->dma_pages_cnt; i++) {
+ dma = &pool->dma_pages[i];
+ if (*dma) {
+ dma_unmap_page_attrs(pool->dev, *dma, PAGE_SIZE,
+ DMA_BIDIRECTIONAL, attrs);
+ *dma = 0;
+ }
+ }
+
+ kvfree(pool->dma_pages);
+ pool->dma_pages_cnt = 0;
+ pool->dev = NULL;
+}
+EXPORT_SYMBOL(xp_dma_unmap);
+
+static void xp_check_dma_contiguity(struct xsk_buff_pool *pool)
+{
+ u32 i;
+
+ for (i = 0; i < pool->dma_pages_cnt - 1; i++) {
+ if (pool->dma_pages[i] + PAGE_SIZE == pool->dma_pages[i + 1])
+ pool->dma_pages[i] |= XSK_NEXT_PG_CONTIG_MASK;
+ else
+ pool->dma_pages[i] &= ~XSK_NEXT_PG_CONTIG_MASK;
+ }
+}
+
+static bool xp_check_cheap_dma(struct xsk_buff_pool *pool)
+{
+ const struct dma_map_ops *ops = get_dma_ops(pool->dev);
+ phys_addr_t paddr;
+ u32 i;
+
+ if (ops) {
+ return !ops->sync_single_for_cpu &&
+ !ops->sync_single_for_device;
+ }
+
+ if (!dma_is_direct(ops))
+ return false;
+
+#if defined(CONFIG_SWIOTLB)
+ for (i = 0; i < pool->dma_pages_cnt; i++) {
+ paddr = dma_to_phys(pool->dev, pool->dma_pages[i]);
+ if (is_swiotlb_buffer(paddr))
+ return false;
+ }
+#endif
+
+ if (!dev_is_dma_coherent(pool->dev)) {
+#if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \
+ defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL) || \
+ defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE)
+ return false;
+#endif
+ }
+ return true;
+}
+
+int xp_dma_map(struct xsk_buff_pool *pool, struct device *dev,
+ unsigned long attrs, struct page **pages, u32 nr_pages)
+{
+ dma_addr_t dma;
+ u32 i;
+
+ pool->dma_pages = kvcalloc(nr_pages, sizeof(*pool->dma_pages),
+ GFP_KERNEL);
+ if (!pool->dma_pages)
+ return -ENOMEM;
+
+ pool->dev = dev;
+ pool->dma_pages_cnt = nr_pages;
+
+ for (i = 0; i < pool->dma_pages_cnt; i++) {
+ dma = dma_map_page_attrs(dev, pages[i], 0, PAGE_SIZE,
+ DMA_BIDIRECTIONAL, attrs);
+ if (dma_mapping_error(dev, dma)) {
+ xp_dma_unmap(pool, attrs);
+ return -ENOMEM;
+ }
+ pool->dma_pages[i] = dma;
+ }
+
+ if (pool->unaligned)
+ xp_check_dma_contiguity(pool);
+
+ pool->dev = dev;
+ pool->cheap_dma = xp_check_cheap_dma(pool);
+ return 0;
+}
+EXPORT_SYMBOL(xp_dma_map);
+
+static bool xp_desc_crosses_non_contig_pg(struct xsk_buff_pool *pool,
+ u64 addr, u32 len)
+{
+ bool cross_pg = (addr & (PAGE_SIZE - 1)) + len > PAGE_SIZE;
+
+ if (pool->dma_pages_cnt && cross_pg) {
+ return !(pool->dma_pages[addr >> PAGE_SHIFT] &
+ XSK_NEXT_PG_CONTIG_MASK);
+ }
+ return false;
+}
+
+static bool xp_addr_crosses_non_contig_pg(struct xsk_buff_pool *pool,
+ u64 addr)
+{
+ return xp_desc_crosses_non_contig_pg(pool, addr, pool->chunk_size);
+}
+
+void xp_release(struct xdp_buff_xsk *xskb)
+{
+ xskb->pool->free_heads[xskb->pool->free_heads_cnt++] = xskb;
+}
+
+static u64 xp_aligned_extract_addr(struct xsk_buff_pool *pool, u64 addr)
+{
+ return addr & pool->chunk_mask;
+}
+
+static u64 xp_unaligned_extract_addr(u64 addr)
+{
+ return addr & XSK_UNALIGNED_BUF_ADDR_MASK;
+}
+
+static u64 xp_unaligned_extract_offset(u64 addr)
+{
+ return addr >> XSK_UNALIGNED_BUF_OFFSET_SHIFT;
+}
+
+static u64 xp_unaligned_add_offset_to_addr(u64 addr)
+{
+ return xp_unaligned_extract_addr(addr) +
+ xp_unaligned_extract_offset(addr);
+}
+
+static bool xp_check_unaligned(struct xsk_buff_pool *pool, u64 *addr)
+{
+ *addr = xp_unaligned_extract_addr(*addr);
+ if (*addr >= pool->addrs_cnt ||
+ *addr + pool->chunk_size > pool->addrs_cnt ||
+ xp_addr_crosses_non_contig_pg(pool, *addr))
+ return false;
+ return true;
+}
+
+static bool xp_check_aligned(struct xsk_buff_pool *pool, u64 *addr)
+{
+ *addr = xp_aligned_extract_addr(pool, *addr);
+ return *addr < pool->addrs_cnt;
+}
+
+static struct xdp_buff_xsk *__xp_alloc(struct xsk_buff_pool *pool)
+{
+ struct xdp_buff_xsk *xskb;
+ u64 addr;
+ bool ok;
+
+ if (pool->free_heads_cnt == 0)
+ return NULL;
+
+ xskb = pool->free_heads[--pool->free_heads_cnt];
+
+ for (;;) {
+ if (!xskq_cons_peek_addr_unchecked(pool->fq, &addr)) {
+ xp_release(xskb);
+ return NULL;
+ }
+
+ ok = pool->unaligned ? xp_check_unaligned(pool, &addr) :
+ xp_check_aligned(pool, &addr);
+ if (!ok) {
+ pool->fq->invalid_descs++;
+ xskq_cons_release(pool->fq);
+ continue;
+ }
+ break;
+ }
+ xskq_cons_release(pool->fq);
+
+ xskb->orig_addr = addr;
+ xskb->xdp.data_hard_start = pool->addrs + addr + pool->headroom;
+ if (pool->dma_pages_cnt) {
+ xskb->dma = (pool->dma_pages[addr >> PAGE_SHIFT] &
+ ~XSK_NEXT_PG_CONTIG_MASK) +
+ (addr & ~PAGE_MASK) +
+ pool->headroom + XDP_PACKET_HEADROOM;
+ }
+ return xskb;
+}
+
+struct xdp_buff *xp_alloc(struct xsk_buff_pool *pool)
+{
+ struct xdp_buff_xsk *xskb;
+
+ if (!pool->free_list_cnt) {
+ xskb = __xp_alloc(pool);
+ if (!xskb)
+ return NULL;
+ } else {
+ pool->free_list_cnt--;
+ xskb = list_first_entry(&pool->free_list, struct xdp_buff_xsk,
+ free_list_node);
+ list_del(&xskb->free_list_node);
+ }
+
+ xskb->xdp.data = xskb->xdp.data_hard_start + XDP_PACKET_HEADROOM;
+ xskb->xdp.data_meta = xskb->xdp.data;
+
+ if (!pool->cheap_dma) {
+ dma_sync_single_range_for_device(pool->dev, xskb->dma, 0,
+ pool->frame_len,
+ DMA_BIDIRECTIONAL);
+ }
+ return &xskb->xdp;
+}
+EXPORT_SYMBOL(xp_alloc);
+
+bool xp_can_alloc(struct xsk_buff_pool *pool, u32 count)
+{
+ if (pool->free_list_cnt >= count)
+ return true;
+ return xskq_cons_has_entries(pool->fq, count - pool->free_list_cnt);
+}
+EXPORT_SYMBOL(xp_can_alloc);
+
+void xp_free(struct xdp_buff_xsk *xskb)
+{
+ xskb->pool->free_list_cnt++;
+ list_add(&xskb->free_list_node, &xskb->pool->free_list);
+}
+EXPORT_SYMBOL(xp_free);
+
+static bool xp_aligned_validate_desc(struct xsk_buff_pool *pool,
+ struct xdp_desc *desc)
+{
+ u64 chunk, chunk_end;
+
+ chunk = xp_aligned_extract_addr(pool, desc->addr);
+ chunk_end = xp_aligned_extract_addr(pool, desc->addr + desc->len);
+ if (chunk != chunk_end)
+ return false;
+
+ if (chunk >= pool->addrs_cnt)
+ return false;
+
+ if (desc->options)
+ return false;
+ return true;
+}
+
+static bool xp_unaligned_validate_desc(struct xsk_buff_pool *pool,
+ struct xdp_desc *desc)
+{
+ u64 addr, base_addr;
+
+ base_addr = xp_unaligned_extract_addr(desc->addr);
+ addr = xp_unaligned_add_offset_to_addr(desc->addr);
+
+ if (desc->len > pool->chunk_size)
+ return false;
+
+ if (base_addr >= pool->addrs_cnt || addr >= pool->addrs_cnt ||
+ xp_desc_crosses_non_contig_pg(pool, addr, desc->len))
+ return false;
+
+ if (desc->options)
+ return false;
+ return true;
+}
+
+bool xp_validate_desc(struct xsk_buff_pool *pool, struct xdp_desc *desc)
+{
+ return pool->unaligned ? xp_unaligned_validate_desc(pool, desc) :
+ xp_aligned_validate_desc(pool, desc);
+}
+
+u64 xp_get_handle(struct xdp_buff_xsk *xskb)
+{
+ u64 offset = xskb->xdp.data - xskb->xdp.data_hard_start;
+
+ offset += xskb->pool->headroom;
+ if (!xskb->pool->unaligned)
+ return xskb->orig_addr + offset;
+ return xskb->orig_addr + (offset << XSK_UNALIGNED_BUF_OFFSET_SHIFT);
+}
+
+void *xp_raw_get_data(struct xsk_buff_pool *pool, u64 addr)
+{
+ addr = pool->unaligned ? xp_unaligned_add_offset_to_addr(addr) : addr;
+ return pool->addrs + addr;
+}
+EXPORT_SYMBOL(xp_raw_get_data);
+
+dma_addr_t xp_raw_get_dma(struct xsk_buff_pool *pool, u64 addr)
+{
+ addr = pool->unaligned ? xp_unaligned_add_offset_to_addr(addr) : addr;
+ return (pool->dma_pages[addr >> PAGE_SHIFT] &
+ ~XSK_NEXT_PG_CONTIG_MASK) +
+ (addr & ~PAGE_MASK);
+}
+EXPORT_SYMBOL(xp_raw_get_dma);
+
+dma_addr_t xp_get_dma(struct xdp_buff_xsk *xskb)
+{
+ return xskb->dma;
+}
+EXPORT_SYMBOL(xp_get_dma);
+
+void xp_dma_sync_for_cpu(struct xdp_buff_xsk *xskb)
+{
+ size_t size;
+
+ if (xskb->pool->cheap_dma)
+ return;
+
+ size = xskb->xdp.data_end - xskb->xdp.data;
+ dma_sync_single_range_for_cpu(xskb->pool->dev, xskb->dma, 0,
+ size, DMA_BIDIRECTIONAL);
+}
+EXPORT_SYMBOL(xp_dma_sync_for_cpu);
+
+void xp_dma_sync_for_device(struct xsk_buff_pool *pool, dma_addr_t dma,
+ size_t size)
+{
+ if (pool->cheap_dma)
+ return;
+
+ dma_sync_single_range_for_device(pool->dev, dma, 0,
+ size, DMA_BIDIRECTIONAL);
+}
+EXPORT_SYMBOL(xp_dma_sync_for_device);
diff --git a/net/xdp/xsk_diag.c b/net/xdp/xsk_diag.c
index f59791ba43a0..0163b26aaf63 100644
--- a/net/xdp/xsk_diag.c
+++ b/net/xdp/xsk_diag.c
@@ -56,7 +56,7 @@ static int xsk_diag_put_umem(const struct xdp_sock *xs, struct sk_buff *nlskb)
du.id = umem->id;
du.size = umem->size;
du.num_pages = umem->npgs;
- du.chunk_size = umem->chunk_size_nohr + umem->headroom;
+ du.chunk_size = umem->chunk_size;
du.headroom = umem->headroom;
du.ifindex = umem->dev ? umem->dev->ifindex : 0;
du.queue_id = umem->queue_id;
diff --git a/net/xdp/xsk_queue.h b/net/xdp/xsk_queue.h
index aa3dd35cbfb6..db25da8fb2b9 100644
--- a/net/xdp/xsk_queue.h
+++ b/net/xdp/xsk_queue.h
@@ -9,6 +9,7 @@
#include <linux/types.h>
#include <linux/if_xdp.h>
#include <net/xdp_sock.h>
+#include <net/xsk_buff_pool.h>
#include "xsk.h"
@@ -172,31 +173,45 @@ static inline bool xskq_cons_read_addr(struct xsk_queue *q, u64 *addr,
return false;
}
-static inline bool xskq_cons_is_valid_desc(struct xsk_queue *q,
- struct xdp_desc *d,
- struct xdp_umem *umem)
+static inline bool xskq_cons_read_addr_aligned(struct xsk_queue *q, u64 *addr)
{
- if (umem->flags & XDP_UMEM_UNALIGNED_CHUNK_FLAG) {
- if (!xskq_cons_is_valid_unaligned(q, d->addr, d->len, umem))
- return false;
+ struct xdp_umem_ring *ring = (struct xdp_umem_ring *)q->ring;
- if (d->len > umem->chunk_size_nohr || d->options) {
- q->invalid_descs++;
- return false;
- }
+ while (q->cached_cons != q->cached_prod) {
+ u32 idx = q->cached_cons & q->ring_mask;
+
+ *addr = ring->desc[idx];
+ if (xskq_cons_is_valid_addr(q, *addr))
+ return true;
+ q->cached_cons++;
+ }
+
+ return false;
+}
+
+static inline bool xskq_cons_read_addr_unchecked(struct xsk_queue *q, u64 *addr)
+{
+ struct xdp_umem_ring *ring = (struct xdp_umem_ring *)q->ring;
+
+ if (q->cached_cons != q->cached_prod) {
+ u32 idx = q->cached_cons & q->ring_mask;
+
+ *addr = ring->desc[idx];
return true;
}
- if (!xskq_cons_is_valid_addr(q, d->addr))
- return false;
+ return false;
+}
- if (((d->addr + d->len) & q->chunk_mask) != (d->addr & q->chunk_mask) ||
- d->options) {
+static inline bool xskq_cons_is_valid_desc(struct xsk_queue *q,
+ struct xdp_desc *d,
+ struct xdp_umem *umem)
+{
+ if (!xp_validate_desc(umem->pool, d)) {
q->invalid_descs++;
return false;
}
-
return true;
}
@@ -260,6 +275,20 @@ static inline bool xskq_cons_peek_addr(struct xsk_queue *q, u64 *addr,
return xskq_cons_read_addr(q, addr, umem);
}
+static inline bool xskq_cons_peek_addr_aligned(struct xsk_queue *q, u64 *addr)
+{
+ if (q->cached_prod == q->cached_cons)
+ xskq_cons_get_entries(q);
+ return xskq_cons_read_addr_aligned(q, addr);
+}
+
+static inline bool xskq_cons_peek_addr_unchecked(struct xsk_queue *q, u64 *addr)
+{
+ if (q->cached_prod == q->cached_cons)
+ xskq_cons_get_entries(q);
+ return xskq_cons_read_addr_unchecked(q, addr);
+}
+
static inline bool xskq_cons_peek_desc(struct xsk_queue *q,
struct xdp_desc *desc,
struct xdp_umem *umem)
--
2.25.1
