diff mbox series

[net-next,03/12] xdp: make __xdp_return() MP-agnostic

Message ID 20241211172649.761483-4-aleksander.lobakin@intel.com (mailing list archive)
State New
Delegated to: Netdev Maintainers
Headers show
Series xdp: a fistful of generic changes pt. II | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next, async
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 2 this patch: 2
netdev/build_tools success Errors and warnings before: 0 (+23) this patch: 0 (+23)
netdev/cc_maintainers warning 10 maintainers not CCed: haoluo@google.com jolsa@kernel.org yonghong.song@linux.dev kpsingh@kernel.org sdf@fomichev.me hawk@kernel.org song@kernel.org martin.lau@linux.dev eddyz87@gmail.com horms@kernel.org
netdev/build_clang success Errors and warnings before: 6 this patch: 6
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 234 this patch: 234
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 135 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 6 this patch: 6
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-12-12--00-00 (tests: 764)

Commit Message

Alexander Lobakin Dec. 11, 2024, 5:26 p.m. UTC
Currently, __xdp_return() takes pointer to the virtual memory to free
a buffer. Apart from that this sometimes provokes redundant
data <--> page conversions, taking data pointer effectively prevents
lots of XDP code to support non-page-backed buffers, as there's no
mapping for the non-host memory (data is always NULL).
Just convert it to always take netmem reference. For
xdp_return_{buff,frame*}(), this chops off one page_address() per each
frag and adds one virt_to_netmem() (same as virt_to_page()) per header
buffer. For __xdp_return() itself, it removes one virt_to_page() for
MEM_TYPE_PAGE_POOL and another one for MEM_TYPE_PAGE_ORDER0, adding
one page_address() for [not really common nowadays]
MEM_TYPE_PAGE_SHARED, but the main effect is that the abovementioned
functions won't die or memleak anymore if the frame has non-host memory
attached and will correctly free those.

Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
---
 include/net/xdp.h |  4 ++--
 net/core/filter.c |  9 +++------
 net/core/xdp.c    | 47 +++++++++++++++++++----------------------------
 3 files changed, 24 insertions(+), 36 deletions(-)
diff mbox series

Patch

diff --git a/include/net/xdp.h b/include/net/xdp.h
index 1c260869a353..d2089cfecefd 100644
--- a/include/net/xdp.h
+++ b/include/net/xdp.h
@@ -312,8 +312,8 @@  struct xdp_frame *xdp_convert_buff_to_frame(struct xdp_buff *xdp)
 	return xdp_frame;
 }
 
-void __xdp_return(void *data, enum xdp_mem_type mem_type, bool napi_direct,
-		  struct xdp_buff *xdp);
+void __xdp_return(netmem_ref netmem, enum xdp_mem_type mem_type,
+		  bool napi_direct, struct xdp_buff *xdp);
 void xdp_return_frame(struct xdp_frame *xdpf);
 void xdp_return_frame_rx_napi(struct xdp_frame *xdpf);
 void xdp_return_buff(struct xdp_buff *xdp);
diff --git a/net/core/filter.c b/net/core/filter.c
index 6c036708634b..5fea874025d3 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -4125,7 +4125,7 @@  static void bpf_xdp_shrink_data_zc(struct xdp_buff *xdp, int shrink,
 
 	if (release) {
 		xsk_buff_del_tail(zc_frag);
-		__xdp_return(NULL, mem_type, false, zc_frag);
+		__xdp_return(0, mem_type, false, zc_frag);
 	} else {
 		zc_frag->data_end -= shrink;
 	}
@@ -4142,11 +4142,8 @@  static bool bpf_xdp_shrink_data(struct xdp_buff *xdp, skb_frag_t *frag,
 		goto out;
 	}
 
-	if (release) {
-		struct page *page = skb_frag_page(frag);
-
-		__xdp_return(page_address(page), mem_type, false, NULL);
-	}
+	if (release)
+		__xdp_return(skb_frag_netmem(frag), mem_type, false, NULL);
 
 out:
 	return release;
diff --git a/net/core/xdp.c b/net/core/xdp.c
index d367571c5838..f1165a35411b 100644
--- a/net/core/xdp.c
+++ b/net/core/xdp.c
@@ -430,27 +430,25 @@  EXPORT_SYMBOL_GPL(xdp_rxq_info_attach_page_pool);
  * is used for those calls sites.  Thus, allowing for faster recycling
  * of xdp_frames/pages in those cases.
  */
-void __xdp_return(void *data, enum xdp_mem_type mem_type, bool napi_direct,
-		  struct xdp_buff *xdp)
+void __xdp_return(netmem_ref netmem, enum xdp_mem_type mem_type,
+		  bool napi_direct, struct xdp_buff *xdp)
 {
-	struct page *page;
-
 	switch (mem_type) {
 	case MEM_TYPE_PAGE_POOL:
-		page = virt_to_head_page(data);
+		netmem = netmem_compound_head(netmem);
 		if (napi_direct && xdp_return_frame_no_direct())
 			napi_direct = false;
 		/* No need to check ((page->pp_magic & ~0x3UL) == PP_SIGNATURE)
 		 * as mem->type knows this a page_pool page
 		 */
-		page_pool_put_full_page(page->pp, page, napi_direct);
+		page_pool_put_full_netmem(netmem_get_pp(netmem), netmem,
+					  napi_direct);
 		break;
 	case MEM_TYPE_PAGE_SHARED:
-		page_frag_free(data);
+		page_frag_free(__netmem_address(netmem));
 		break;
 	case MEM_TYPE_PAGE_ORDER0:
-		page = virt_to_page(data); /* Assumes order0 page*/
-		put_page(page);
+		put_page(__netmem_to_page(netmem));
 		break;
 	case MEM_TYPE_XSK_BUFF_POOL:
 		/* NB! Only valid from an xdp_buff! */
@@ -466,38 +464,34 @@  void __xdp_return(void *data, enum xdp_mem_type mem_type, bool napi_direct,
 void xdp_return_frame(struct xdp_frame *xdpf)
 {
 	struct skb_shared_info *sinfo;
-	int i;
 
 	if (likely(!xdp_frame_has_frags(xdpf)))
 		goto out;
 
 	sinfo = xdp_get_shared_info_from_frame(xdpf);
-	for (i = 0; i < sinfo->nr_frags; i++) {
-		struct page *page = skb_frag_page(&sinfo->frags[i]);
+	for (u32 i = 0; i < sinfo->nr_frags; i++)
+		__xdp_return(skb_frag_netmem(&sinfo->frags[i]), xdpf->mem_type,
+			     false, NULL);
 
-		__xdp_return(page_address(page), xdpf->mem_type, false, NULL);
-	}
 out:
-	__xdp_return(xdpf->data, xdpf->mem_type, false, NULL);
+	__xdp_return(virt_to_netmem(xdpf->data), xdpf->mem_type, false, NULL);
 }
 EXPORT_SYMBOL_GPL(xdp_return_frame);
 
 void xdp_return_frame_rx_napi(struct xdp_frame *xdpf)
 {
 	struct skb_shared_info *sinfo;
-	int i;
 
 	if (likely(!xdp_frame_has_frags(xdpf)))
 		goto out;
 
 	sinfo = xdp_get_shared_info_from_frame(xdpf);
-	for (i = 0; i < sinfo->nr_frags; i++) {
-		struct page *page = skb_frag_page(&sinfo->frags[i]);
+	for (u32 i = 0; i < sinfo->nr_frags; i++)
+		__xdp_return(skb_frag_netmem(&sinfo->frags[i]), xdpf->mem_type,
+			     true, NULL);
 
-		__xdp_return(page_address(page), xdpf->mem_type, true, NULL);
-	}
 out:
-	__xdp_return(xdpf->data, xdpf->mem_type, true, NULL);
+	__xdp_return(virt_to_netmem(xdpf->data), xdpf->mem_type, true, NULL);
 }
 EXPORT_SYMBOL_GPL(xdp_return_frame_rx_napi);
 
@@ -544,20 +538,17 @@  EXPORT_SYMBOL_GPL(xdp_return_frame_bulk);
 void xdp_return_buff(struct xdp_buff *xdp)
 {
 	struct skb_shared_info *sinfo;
-	int i;
 
 	if (likely(!xdp_buff_has_frags(xdp)))
 		goto out;
 
 	sinfo = xdp_get_shared_info_from_buff(xdp);
-	for (i = 0; i < sinfo->nr_frags; i++) {
-		struct page *page = skb_frag_page(&sinfo->frags[i]);
+	for (u32 i = 0; i < sinfo->nr_frags; i++)
+		__xdp_return(skb_frag_netmem(&sinfo->frags[i]),
+			     xdp->rxq->mem.type, true, xdp);
 
-		__xdp_return(page_address(page), xdp->rxq->mem.type, true,
-			     xdp);
-	}
 out:
-	__xdp_return(xdp->data, xdp->rxq->mem.type, true, xdp);
+	__xdp_return(virt_to_netmem(xdp->data), xdp->rxq->mem.type, true, xdp);
 }
 EXPORT_SYMBOL_GPL(xdp_return_buff);