diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2017-02-04 21:44:15 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-02-04 21:44:15 +0300 |
commit | 412e6d3fec247b2bc83106514b0fb3b17e2eb7fe (patch) | |
tree | cbd241740a61d7ff60742d6f94d1564e796fb405 /include | |
parent | 252bf9f4c43fd58f96587a97866cb7cc980e7544 (diff) | |
parent | 433e19cf33d34bb6751c874a9c00980552fe508c (diff) | |
download | linux-412e6d3fec247b2bc83106514b0fb3b17e2eb7fe.tar.xz |
Merge tag 'char-misc-4.10-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver fixes from Greg KH:
"Here are two bugfixes that resolve some reported issues. One in the
firmware loader, that should fix the much-reported problem of crashes
with it. The other is a hyperv fix for a reported regression.
Both have been in linux-next for a week or so with no reported issues"
* tag 'char-misc-4.10-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
Drivers: hv: vmbus: finally fix hv_need_to_signal_on_read()
firmware: fix NULL pointer dereference in __fw_load_abort()
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/hyperv.h | 32 |
1 files changed, 30 insertions, 2 deletions
diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h index 42fe43fb0c80..183efde54269 100644 --- a/include/linux/hyperv.h +++ b/include/linux/hyperv.h @@ -128,6 +128,7 @@ struct hv_ring_buffer_info { u32 ring_data_startoffset; u32 priv_write_index; u32 priv_read_index; + u32 cached_read_index; }; /* @@ -180,6 +181,19 @@ static inline u32 hv_get_bytes_to_write(struct hv_ring_buffer_info *rbi) return write; } +static inline u32 hv_get_cached_bytes_to_write( + const struct hv_ring_buffer_info *rbi) +{ + u32 read_loc, write_loc, dsize, write; + + dsize = rbi->ring_datasize; + read_loc = rbi->cached_read_index; + write_loc = rbi->ring_buffer->write_index; + + write = write_loc >= read_loc ? dsize - (write_loc - read_loc) : + read_loc - write_loc; + return write; +} /* * VMBUS version is 32 bit entity broken up into * two 16 bit quantities: major_number. minor_number. @@ -1488,7 +1502,7 @@ hv_get_ring_buffer(struct hv_ring_buffer_info *ring_info) static inline void hv_signal_on_read(struct vmbus_channel *channel) { - u32 cur_write_sz; + u32 cur_write_sz, cached_write_sz; u32 pending_sz; struct hv_ring_buffer_info *rbi = &channel->inbound; @@ -1512,12 +1526,24 @@ static inline void hv_signal_on_read(struct vmbus_channel *channel) cur_write_sz = hv_get_bytes_to_write(rbi); - if (cur_write_sz >= pending_sz) + if (cur_write_sz < pending_sz) + return; + + cached_write_sz = hv_get_cached_bytes_to_write(rbi); + if (cached_write_sz < pending_sz) vmbus_setevent(channel); return; } +static inline void +init_cached_read_index(struct vmbus_channel *channel) +{ + struct hv_ring_buffer_info *rbi = &channel->inbound; + + rbi->cached_read_index = rbi->ring_buffer->read_index; +} + /* * An API to support in-place processing of incoming VMBUS packets. */ @@ -1569,6 +1595,8 @@ static inline void put_pkt_raw(struct vmbus_channel *channel, * This call commits the read index and potentially signals the host. * Here is the pattern for using the "in-place" consumption APIs: * + * init_cached_read_index(); + * * while (get_next_pkt_raw() { * process the packet "in-place"; * put_pkt_raw(); |