From 06b4feb37e64e543714c971a4162a75e2e4024d4 Mon Sep 17 00:00:00 2001 From: Jonathan Lemon Date: Wed, 6 Jan 2021 14:18:38 -0800 Subject: [PATCH] net: group skb_shinfo zerocopy related bits together. In preparation for expanded zerocopy (TX and RX), move the zerocopy related bits out of tx_flags into their own flag word. Signed-off-by: Jonathan Lemon Signed-off-by: Jakub Kicinski --- drivers/net/tap.c | 3 +-- drivers/net/tun.c | 3 +-- drivers/net/xen-netback/interface.c | 4 ++-- include/linux/skbuff.h | 38 ++++++++++++++++++++----------------- net/core/skbuff.c | 9 ++++----- net/ipv4/tcp.c | 2 +- net/kcm/kcmsock.c | 4 ++-- 7 files changed, 32 insertions(+), 31 deletions(-) diff --git a/drivers/net/tap.c b/drivers/net/tap.c index 3f51f3766d18..f7a19d9b7c27 100644 --- a/drivers/net/tap.c +++ b/drivers/net/tap.c @@ -723,8 +723,7 @@ static ssize_t tap_get_user(struct tap_queue *q, void *msg_control, /* copy skb_ubuf_info for callback when skb has no error */ if (zerocopy) { skb_shinfo(skb)->destructor_arg = msg_control; - skb_shinfo(skb)->tx_flags |= SKBTX_DEV_ZEROCOPY; - skb_shinfo(skb)->tx_flags |= SKBTX_SHARED_FRAG; + skb_shinfo(skb)->flags |= SKBFL_ZEROCOPY_FRAG; } else if (msg_control) { struct ubuf_info *uarg = msg_control; uarg->callback(NULL, uarg, false); diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 862c9063aa09..d8f1c3d34612 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -1815,8 +1815,7 @@ drop: /* copy skb_ubuf_info for callback when skb has no error */ if (zerocopy) { skb_shinfo(skb)->destructor_arg = msg_control; - skb_shinfo(skb)->tx_flags |= SKBTX_DEV_ZEROCOPY; - skb_shinfo(skb)->tx_flags |= SKBTX_SHARED_FRAG; + skb_shinfo(skb)->flags |= SKBFL_ZEROCOPY_FRAG; } else if (msg_control) { struct ubuf_info *uarg = msg_control; uarg->callback(NULL, uarg, false); diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c index acb786d8b1d8..08b0e3d0b7eb 100644 --- a/drivers/net/xen-netback/interface.c +++ b/drivers/net/xen-netback/interface.c @@ -47,7 +47,7 @@ /* Number of bytes allowed on the internal guest Rx queue. */ #define XENVIF_RX_QUEUE_BYTES (XEN_NETIF_RX_RING_SIZE/2 * PAGE_SIZE) -/* This function is used to set SKBTX_DEV_ZEROCOPY as well as +/* This function is used to set SKBFL_ZEROCOPY_ENABLE as well as * increasing the inflight counter. We need to increase the inflight * counter because core driver calls into xenvif_zerocopy_callback * which calls xenvif_skb_zerocopy_complete. @@ -55,7 +55,7 @@ void xenvif_skb_zerocopy_prepare(struct xenvif_queue *queue, struct sk_buff *skb) { - skb_shinfo(skb)->tx_flags |= SKBTX_DEV_ZEROCOPY; + skb_shinfo(skb)->flags |= SKBFL_ZEROCOPY_ENABLE; atomic_inc(&queue->inflight_packets); } diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index f6a3cee5c967..7b5adc511ac6 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -430,28 +430,32 @@ enum { /* device driver is going to provide hardware time stamp */ SKBTX_IN_PROGRESS = 1 << 2, - /* device driver supports TX zero-copy buffers */ - SKBTX_DEV_ZEROCOPY = 1 << 3, - /* generate wifi status information (where possible) */ SKBTX_WIFI_STATUS = 1 << 4, - /* This indicates at least one fragment might be overwritten - * (as in vmsplice(), sendfile() ...) - * If we need to compute a TX checksum, we'll need to copy - * all frags to avoid possible bad checksum - */ - SKBTX_SHARED_FRAG = 1 << 5, - /* generate software time stamp when entering packet scheduling */ SKBTX_SCHED_TSTAMP = 1 << 6, }; -#define SKBTX_ZEROCOPY_FRAG (SKBTX_DEV_ZEROCOPY | SKBTX_SHARED_FRAG) #define SKBTX_ANY_SW_TSTAMP (SKBTX_SW_TSTAMP | \ SKBTX_SCHED_TSTAMP) #define SKBTX_ANY_TSTAMP (SKBTX_HW_TSTAMP | SKBTX_ANY_SW_TSTAMP) +/* Definitions for flags in struct skb_shared_info */ +enum { + /* use zcopy routines */ + SKBFL_ZEROCOPY_ENABLE = BIT(0), + + /* This indicates at least one fragment might be overwritten + * (as in vmsplice(), sendfile() ...) + * If we need to compute a TX checksum, we'll need to copy + * all frags to avoid possible bad checksum + */ + SKBFL_SHARED_FRAG = BIT(1), +}; + +#define SKBFL_ZEROCOPY_FRAG (SKBFL_ZEROCOPY_ENABLE | SKBFL_SHARED_FRAG) + /* * The callback notifies userspace to release buffers when skb DMA is done in * lower device, the skb last reference should be 0 when calling this. @@ -506,7 +510,7 @@ int skb_zerocopy_iter_stream(struct sock *sk, struct sk_buff *skb, * the end of the header data, ie. at skb->end. */ struct skb_shared_info { - __u8 __unused; + __u8 flags; __u8 meta_len; __u8 nr_frags; __u8 tx_flags; @@ -1433,7 +1437,7 @@ static inline struct skb_shared_hwtstamps *skb_hwtstamps(struct sk_buff *skb) static inline struct ubuf_info *skb_zcopy(struct sk_buff *skb) { - bool is_zcopy = skb && skb_shinfo(skb)->tx_flags & SKBTX_DEV_ZEROCOPY; + bool is_zcopy = skb && skb_shinfo(skb)->flags & SKBFL_ZEROCOPY_ENABLE; return is_zcopy ? skb_uarg(skb) : NULL; } @@ -1452,14 +1456,14 @@ static inline void skb_zcopy_set(struct sk_buff *skb, struct ubuf_info *uarg, else skb_zcopy_get(uarg); skb_shinfo(skb)->destructor_arg = uarg; - skb_shinfo(skb)->tx_flags |= SKBTX_ZEROCOPY_FRAG; + skb_shinfo(skb)->flags |= SKBFL_ZEROCOPY_FRAG; } } static inline void skb_zcopy_set_nouarg(struct sk_buff *skb, void *val) { skb_shinfo(skb)->destructor_arg = (void *)((uintptr_t) val | 0x1UL); - skb_shinfo(skb)->tx_flags |= SKBTX_ZEROCOPY_FRAG; + skb_shinfo(skb)->flags |= SKBFL_ZEROCOPY_FRAG; } static inline bool skb_zcopy_is_nouarg(struct sk_buff *skb) @@ -1497,7 +1501,7 @@ static inline void skb_zcopy_clear(struct sk_buff *skb, bool zerocopy_success) if (!skb_zcopy_is_nouarg(skb)) uarg->callback(skb, uarg, zerocopy_success); - skb_shinfo(skb)->tx_flags &= ~SKBTX_ZEROCOPY_FRAG; + skb_shinfo(skb)->flags &= ~SKBFL_ZEROCOPY_FRAG; } } @@ -3323,7 +3327,7 @@ static inline int skb_linearize(struct sk_buff *skb) static inline bool skb_has_shared_frag(const struct sk_buff *skb) { return skb_is_nonlinear(skb) && - skb_shinfo(skb)->tx_flags & SKBTX_SHARED_FRAG; + skb_shinfo(skb)->flags & SKBFL_SHARED_FRAG; } /** diff --git a/net/core/skbuff.c b/net/core/skbuff.c index bcd56763952e..5b9e52cbd087 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -1327,7 +1327,7 @@ static int skb_zerocopy_clone(struct sk_buff *nskb, struct sk_buff *orig, * @skb: the skb to modify * @gfp_mask: allocation priority * - * This must be called on SKBTX_DEV_ZEROCOPY skb. + * This must be called on skb with SKBFL_ZEROCOPY_ENABLE. * It will copy all frags into kernel and drop the reference * to userspace pages. * @@ -3264,8 +3264,7 @@ void skb_split(struct sk_buff *skb, struct sk_buff *skb1, const u32 len) { int pos = skb_headlen(skb); - skb_shinfo(skb1)->tx_flags |= skb_shinfo(skb)->tx_flags & - SKBTX_SHARED_FRAG; + skb_shinfo(skb1)->flags |= skb_shinfo(skb)->flags & SKBFL_SHARED_FRAG; skb_zerocopy_clone(skb1, skb, 0); if (len < pos) /* Split line is inside header. */ skb_split_inside_header(skb, skb1, len, pos); @@ -3954,8 +3953,8 @@ normal: skb_copy_from_linear_data_offset(head_skb, offset, skb_put(nskb, hsize), hsize); - skb_shinfo(nskb)->tx_flags |= skb_shinfo(head_skb)->tx_flags & - SKBTX_SHARED_FRAG; + skb_shinfo(nskb)->flags |= skb_shinfo(head_skb)->flags & + SKBFL_SHARED_FRAG; if (skb_orphan_frags(frag_skb, GFP_ATOMIC) || skb_zerocopy_clone(nskb, frag_skb, GFP_ATOMIC)) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 2882d520f5b1..1954190b33c7 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -1010,7 +1010,7 @@ new_segment: } if (!(flags & MSG_NO_SHARED_FRAGS)) - skb_shinfo(skb)->tx_flags |= SKBTX_SHARED_FRAG; + skb_shinfo(skb)->flags |= SKBFL_SHARED_FRAG; skb->len += copy; skb->data_len += copy; diff --git a/net/kcm/kcmsock.c b/net/kcm/kcmsock.c index a9eb616f5521..d0b56ffbb057 100644 --- a/net/kcm/kcmsock.c +++ b/net/kcm/kcmsock.c @@ -786,7 +786,7 @@ static ssize_t kcm_sendpage(struct socket *sock, struct page *page, if (skb_can_coalesce(skb, i, page, offset)) { skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], size); - skb_shinfo(skb)->tx_flags |= SKBTX_SHARED_FRAG; + skb_shinfo(skb)->flags |= SKBFL_SHARED_FRAG; goto coalesced; } @@ -834,7 +834,7 @@ static ssize_t kcm_sendpage(struct socket *sock, struct page *page, get_page(page); skb_fill_page_desc(skb, i, page, offset, size); - skb_shinfo(skb)->tx_flags |= SKBTX_SHARED_FRAG; + skb_shinfo(skb)->flags |= SKBFL_SHARED_FRAG; coalesced: skb->len += size; -- 2.11.0