Revert "Drivers: hv: vmbus: Copy packets sent by Hyper-V out of the ring buffer"
authorWei Liu <wei.liu@kernel.org>
Mon, 15 Feb 2021 10:44:58 +0000 (10:44 +0000)
committerWei Liu <wei.liu@kernel.org>
Mon, 15 Feb 2021 10:49:11 +0000 (10:49 +0000)
This reverts commit a8c3209998afb5c4941b49e35b513cea9050cb4a.

It is reported that the said commit caused regression in netvsc.

Reported-by: Andrea Parri (Microsoft) <parri.andrea@gmail.com>
Signed-off-by: Wei Liu <wei.liu@kernel.org>
drivers/hv/channel.c
drivers/hv/hv_fcopy.c
drivers/hv/hv_kvp.c
drivers/hv/hyperv_vmbus.h
drivers/hv/ring_buffer.c
drivers/net/hyperv/hyperv_net.h
drivers/net/hyperv/netvsc.c
drivers/net/hyperv/rndis_filter.c
drivers/scsi/storvsc_drv.c
include/linux/hyperv.h
net/vmw_vsock/hyperv_transport.c

index 9aa789e5f22bb908401f5fd4d6de55c9b17aebbe..0bd202de79600393062817ffa160222cd737074d 100644 (file)
@@ -597,15 +597,12 @@ static int __vmbus_open(struct vmbus_channel *newchannel,
        newchannel->onchannel_callback = onchannelcallback;
        newchannel->channel_callback_context = context;
 
-       if (!newchannel->max_pkt_size)
-               newchannel->max_pkt_size = VMBUS_DEFAULT_MAX_PKT_SIZE;
-
-       err = hv_ringbuffer_init(&newchannel->outbound, page, send_pages, 0);
+       err = hv_ringbuffer_init(&newchannel->outbound, page, send_pages);
        if (err)
                goto error_clean_ring;
 
-       err = hv_ringbuffer_init(&newchannel->inbound, &page[send_pages],
-                                recv_pages, newchannel->max_pkt_size);
+       err = hv_ringbuffer_init(&newchannel->inbound,
+                                &page[send_pages], recv_pages);
        if (err)
                goto error_clean_ring;
 
index 660036da744953ef93ccd204df470b04e64daaee..59ce85e00a028fed5f26c26c1f16ad9a87ed3f70 100644 (file)
@@ -349,7 +349,6 @@ int hv_fcopy_init(struct hv_util_service *srv)
 {
        recv_buffer = srv->recv_buffer;
        fcopy_transaction.recv_channel = srv->channel;
-       fcopy_transaction.recv_channel->max_pkt_size = HV_HYP_PAGE_SIZE * 2;
 
        /*
         * When this driver loads, the user level daemon that
index c698592b83e421a6e98c1701ddc76b3333710ef3..b49962d312cefd40206df794963685d2e33b8c9d 100644 (file)
@@ -757,7 +757,6 @@ hv_kvp_init(struct hv_util_service *srv)
 {
        recv_buffer = srv->recv_buffer;
        kvp_transaction.recv_channel = srv->channel;
-       kvp_transaction.recv_channel->max_pkt_size = HV_HYP_PAGE_SIZE * 4;
 
        /*
         * When this driver loads, the user level daemon that
index 42f3d9d123a12dab1e83f5087d2f745a77b70423..9416e09ebd58cf9112fc7a66731629f1a04c76b9 100644 (file)
@@ -174,7 +174,7 @@ extern int hv_synic_cleanup(unsigned int cpu);
 void hv_ringbuffer_pre_init(struct vmbus_channel *channel);
 
 int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info,
-                      struct page *pages, u32 pagecnt, u32 max_pkt_size);
+                      struct page *pages, u32 pagecnt);
 
 void hv_ringbuffer_cleanup(struct hv_ring_buffer_info *ring_info);
 
index 29e90477363a8496bd05fd6f6d0f03baa26495b4..35833d4d1a1dcac54e136291d5f8b755c7a65044 100644 (file)
@@ -190,7 +190,7 @@ void hv_ringbuffer_pre_init(struct vmbus_channel *channel)
 
 /* Initialize the ring buffer. */
 int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info,
-                      struct page *pages, u32 page_cnt, u32 max_pkt_size)
+                      struct page *pages, u32 page_cnt)
 {
        int i;
        struct page **pages_wraparound;
@@ -232,14 +232,6 @@ int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info,
                sizeof(struct hv_ring_buffer);
        ring_info->priv_read_index = 0;
 
-       /* Initialize buffer that holds copies of incoming packets */
-       if (max_pkt_size) {
-               ring_info->pkt_buffer = kzalloc(max_pkt_size, GFP_KERNEL);
-               if (!ring_info->pkt_buffer)
-                       return -ENOMEM;
-               ring_info->pkt_buffer_size = max_pkt_size;
-       }
-
        spin_lock_init(&ring_info->ring_lock);
 
        return 0;
@@ -252,9 +244,6 @@ void hv_ringbuffer_cleanup(struct hv_ring_buffer_info *ring_info)
        vunmap(ring_info->ring_buffer);
        ring_info->ring_buffer = NULL;
        mutex_unlock(&ring_info->ring_buffer_mutex);
-
-       kfree(ring_info->pkt_buffer);
-       ring_info->pkt_buffer_size = 0;
 }
 
 /* Write to the ring buffer. */
@@ -396,7 +385,7 @@ int hv_ringbuffer_read(struct vmbus_channel *channel,
        memcpy(buffer, (const char *)desc + offset, packetlen);
 
        /* Advance ring index to next packet descriptor */
-       __hv_pkt_iter_next(channel, desc, true);
+       __hv_pkt_iter_next(channel, desc);
 
        /* Notify host of update */
        hv_pkt_iter_close(channel);
@@ -422,22 +411,6 @@ static u32 hv_pkt_iter_avail(const struct hv_ring_buffer_info *rbi)
                return (rbi->ring_datasize - priv_read_loc) + write_loc;
 }
 
-/*
- * Get first vmbus packet without copying it out of the ring buffer
- */
-struct vmpacket_descriptor *hv_pkt_iter_first_raw(struct vmbus_channel *channel)
-{
-       struct hv_ring_buffer_info *rbi = &channel->inbound;
-
-       hv_debug_delay_test(channel, MESSAGE_DELAY);
-
-       if (hv_pkt_iter_avail(rbi) < sizeof(struct vmpacket_descriptor))
-               return NULL;
-
-       return (struct vmpacket_descriptor *)(hv_get_ring_buffer(rbi) + rbi->priv_read_index);
-}
-EXPORT_SYMBOL_GPL(hv_pkt_iter_first_raw);
-
 /*
  * Get first vmbus packet from ring buffer after read_index
  *
@@ -446,49 +419,17 @@ EXPORT_SYMBOL_GPL(hv_pkt_iter_first_raw);
 struct vmpacket_descriptor *hv_pkt_iter_first(struct vmbus_channel *channel)
 {
        struct hv_ring_buffer_info *rbi = &channel->inbound;
-       struct vmpacket_descriptor *desc, *desc_copy;
-       u32 bytes_avail, pkt_len, pkt_offset;
+       struct vmpacket_descriptor *desc;
 
-       desc = hv_pkt_iter_first_raw(channel);
-       if (!desc)
+       hv_debug_delay_test(channel, MESSAGE_DELAY);
+       if (hv_pkt_iter_avail(rbi) < sizeof(struct vmpacket_descriptor))
                return NULL;
 
-       bytes_avail = min(rbi->pkt_buffer_size, hv_pkt_iter_avail(rbi));
-
-       /*
-        * Ensure the compiler does not use references to incoming Hyper-V values (which
-        * could change at any moment) when reading local variables later in the code
-        */
-       pkt_len = READ_ONCE(desc->len8) << 3;
-       pkt_offset = READ_ONCE(desc->offset8) << 3;
-
-       /*
-        * If pkt_len is invalid, set it to the smaller of hv_pkt_iter_avail() and
-        * rbi->pkt_buffer_size
-        */
-       if (pkt_len < sizeof(struct vmpacket_descriptor) || pkt_len > bytes_avail)
-               pkt_len = bytes_avail;
-
-       /*
-        * If pkt_offset is invalid, arbitrarily set it to
-        * the size of vmpacket_descriptor
-        */
-       if (pkt_offset < sizeof(struct vmpacket_descriptor) || pkt_offset > pkt_len)
-               pkt_offset = sizeof(struct vmpacket_descriptor);
-
-       /* Copy the Hyper-V packet out of the ring buffer */
-       desc_copy = (struct vmpacket_descriptor *)rbi->pkt_buffer;
-       memcpy(desc_copy, desc, pkt_len);
-
-       /*
-        * Hyper-V could still change len8 and offset8 after the earlier read.
-        * Ensure that desc_copy has legal values for len8 and offset8 that
-        * are consistent with the copy we just made
-        */
-       desc_copy->len8 = pkt_len >> 3;
-       desc_copy->offset8 = pkt_offset >> 3;
+       desc = hv_get_ring_buffer(rbi) + rbi->priv_read_index;
+       if (desc)
+               prefetch((char *)desc + (desc->len8 << 3));
 
-       return desc_copy;
+       return desc;
 }
 EXPORT_SYMBOL_GPL(hv_pkt_iter_first);
 
@@ -500,8 +441,7 @@ EXPORT_SYMBOL_GPL(hv_pkt_iter_first);
  */
 struct vmpacket_descriptor *
 __hv_pkt_iter_next(struct vmbus_channel *channel,
-                  const struct vmpacket_descriptor *desc,
-                  bool copy)
+                  const struct vmpacket_descriptor *desc)
 {
        struct hv_ring_buffer_info *rbi = &channel->inbound;
        u32 packetlen = desc->len8 << 3;
@@ -514,7 +454,7 @@ __hv_pkt_iter_next(struct vmbus_channel *channel,
                rbi->priv_read_index -= dsize;
 
        /* more data? */
-       return copy ? hv_pkt_iter_first(channel) : hv_pkt_iter_first_raw(channel);
+       return hv_pkt_iter_first(channel);
 }
 EXPORT_SYMBOL_GPL(__hv_pkt_iter_next);
 
index 7ea6936f86efa71077a8045191f87f0c022bfaef..2a87cfa27ac02043d5f4a65024250defbeba0d6f 100644 (file)
@@ -860,12 +860,9 @@ static inline u32 netvsc_rqstor_size(unsigned long ringbytes)
                ringbytes / NETVSC_MIN_IN_MSG_SIZE;
 }
 
-#define NETVSC_MAX_XFER_PAGE_RANGES 375
 #define NETVSC_XFER_HEADER_SIZE(rng_cnt) \
                (offsetof(struct vmtransfer_page_packet_header, ranges) + \
                (rng_cnt) * sizeof(struct vmtransfer_page_range))
-#define NETVSC_MAX_PKT_SIZE (NETVSC_XFER_HEADER_SIZE(NETVSC_MAX_XFER_PAGE_RANGES) + \
-               sizeof(struct nvsp_message) + (sizeof(u32) * VRSS_SEND_TAB_SIZE))
 
 struct multi_send_data {
        struct sk_buff *skb; /* skb containing the pkt */
index 51005f2d4a8211bf3648ccdbf4e7f81034575b73..2353623259f3b5e6d3e36a03fe49590c279b4edd 100644 (file)
@@ -1544,8 +1544,6 @@ struct netvsc_device *netvsc_device_add(struct hv_device *device,
 
        /* Open the channel */
        device->channel->rqstor_size = netvsc_rqstor_size(netvsc_ring_bytes);
-       device->channel->max_pkt_size = NETVSC_MAX_PKT_SIZE;
-
        ret = vmbus_open(device->channel, netvsc_ring_bytes,
                         netvsc_ring_bytes,  NULL, 0,
                         netvsc_channel_cb, net_device->chan_table);
index 7e6dee2f02a43906bfbc3c64b2bdab34b982878e..598713c0d5a8753f1692a82d7f68eb0b83e19375 100644 (file)
@@ -1174,8 +1174,6 @@ static void netvsc_sc_open(struct vmbus_channel *new_sc)
        nvchan->channel = new_sc;
 
        new_sc->rqstor_size = netvsc_rqstor_size(netvsc_ring_bytes);
-       new_sc->max_pkt_size = NETVSC_MAX_PKT_SIZE;
-
        ret = vmbus_open(new_sc, netvsc_ring_bytes,
                         netvsc_ring_bytes, NULL, 0,
                         netvsc_channel_cb, nvchan);
index 7e59284dbf5be5c88f3b534e172a64f03285c8fc..2e4fa77445fdc8007ee24915e68208f2213dfb8c 100644 (file)
@@ -414,14 +414,6 @@ static void storvsc_on_channel_callback(void *context);
 #define STORVSC_IDE_MAX_TARGETS                                1
 #define STORVSC_IDE_MAX_CHANNELS                       1
 
-/*
- * Upper bound on the size of a storvsc packet. vmscsi_size_delta is not
- * included in the calculation because it is set after STORVSC_MAX_PKT_SIZE
- * is used in storvsc_connect_to_vsp
- */
-#define STORVSC_MAX_PKT_SIZE (sizeof(struct vmpacket_descriptor) +\
-                             sizeof(struct vstor_packet))
-
 struct storvsc_cmd_request {
        struct scsi_cmnd *cmd;
 
@@ -706,7 +698,6 @@ static void handle_sc_creation(struct vmbus_channel *new_sc)
                return;
 
        memset(&props, 0, sizeof(struct vmstorage_channel_properties));
-       new_sc->max_pkt_size = STORVSC_MAX_PKT_SIZE;
 
        /*
         * The size of vmbus_requestor is an upper bound on the number of requests
@@ -1289,7 +1280,6 @@ static int storvsc_connect_to_vsp(struct hv_device *device, u32 ring_size,
 
        memset(&props, 0, sizeof(struct vmstorage_channel_properties));
 
-       device->channel->max_pkt_size = STORVSC_MAX_PKT_SIZE;
        /*
         * The size of vmbus_requestor is an upper bound on the number of requests
         * that can be in-progress at any one time across all channels.
index 9dd22af1b7f612d016291b9433eddd0e3230c1e1..f1d74dcf0353f6e32f1bc8c6b7ed26fcc527120c 100644 (file)
@@ -181,10 +181,6 @@ struct hv_ring_buffer_info {
         * being freed while the ring buffer is being accessed.
         */
        struct mutex ring_buffer_mutex;
-
-       /* Buffer that holds a copy of an incoming host packet */
-       void *pkt_buffer;
-       u32 pkt_buffer_size;
 };
 
 
@@ -792,8 +788,6 @@ struct vmbus_device {
        bool allowed_in_isolated;
 };
 
-#define VMBUS_DEFAULT_MAX_PKT_SIZE 4096
-
 struct vmbus_channel {
        struct list_head listentry;
 
@@ -1016,9 +1010,6 @@ struct vmbus_channel {
        /* request/transaction ids for VMBus */
        struct vmbus_requestor requestor;
        u32 rqstor_size;
-
-       /* The max size of a packet on this channel */
-       u32 max_pkt_size;
 };
 
 u64 vmbus_next_request_id(struct vmbus_requestor *rqstor, u64 rqst_addr);
@@ -1660,44 +1651,15 @@ static inline u32 hv_pkt_datalen(const struct vmpacket_descriptor *desc)
 }
 
 
-struct vmpacket_descriptor *
-hv_pkt_iter_first_raw(struct vmbus_channel *channel);
-
 struct vmpacket_descriptor *
 hv_pkt_iter_first(struct vmbus_channel *channel);
 
 struct vmpacket_descriptor *
 __hv_pkt_iter_next(struct vmbus_channel *channel,
-                  const struct vmpacket_descriptor *pkt,
-                  bool copy);
+                  const struct vmpacket_descriptor *pkt);
 
 void hv_pkt_iter_close(struct vmbus_channel *channel);
 
-static inline struct vmpacket_descriptor *
-hv_pkt_iter_next_pkt(struct vmbus_channel *channel,
-                    const struct vmpacket_descriptor *pkt,
-                    bool copy)
-{
-       struct vmpacket_descriptor *nxt;
-
-       nxt = __hv_pkt_iter_next(channel, pkt, copy);
-       if (!nxt)
-               hv_pkt_iter_close(channel);
-
-       return nxt;
-}
-
-/*
- * Get next packet descriptor without copying it out of the ring buffer
- * If at end of list, return NULL and update host.
- */
-static inline struct vmpacket_descriptor *
-hv_pkt_iter_next_raw(struct vmbus_channel *channel,
-                    const struct vmpacket_descriptor *pkt)
-{
-       return hv_pkt_iter_next_pkt(channel, pkt, false);
-}
-
 /*
  * Get next packet descriptor from iterator
  * If at end of list, return NULL and update host.
@@ -1706,7 +1668,13 @@ static inline struct vmpacket_descriptor *
 hv_pkt_iter_next(struct vmbus_channel *channel,
                 const struct vmpacket_descriptor *pkt)
 {
-       return hv_pkt_iter_next_pkt(channel, pkt, true);
+       struct vmpacket_descriptor *nxt;
+
+       nxt = __hv_pkt_iter_next(channel, pkt);
+       if (!nxt)
+               hv_pkt_iter_close(channel);
+
+       return nxt;
 }
 
 #define foreach_vmbus_pkt(pkt, channel) \
index cd8b7c1ca9f152b7501d925f07b29b23a7124949..630b851f8150fd2e67eac5187d75a1771b82f068 100644 (file)
@@ -600,7 +600,7 @@ static ssize_t hvs_stream_dequeue(struct vsock_sock *vsk, struct msghdr *msg,
                return -EOPNOTSUPP;
 
        if (need_refill) {
-               hvs->recv_desc = hv_pkt_iter_first_raw(hvs->chan);
+               hvs->recv_desc = hv_pkt_iter_first(hvs->chan);
                ret = hvs_update_recv_data(hvs);
                if (ret)
                        return ret;
@@ -614,7 +614,7 @@ static ssize_t hvs_stream_dequeue(struct vsock_sock *vsk, struct msghdr *msg,
 
        hvs->recv_data_len -= to_read;
        if (hvs->recv_data_len == 0) {
-               hvs->recv_desc = hv_pkt_iter_next_raw(hvs->chan, hvs->recv_desc);
+               hvs->recv_desc = hv_pkt_iter_next(hvs->chan, hvs->recv_desc);
                if (hvs->recv_desc) {
                        ret = hvs_update_recv_data(hvs);
                        if (ret)