diff options
| -rw-r--r-- | drivers/staging/unisys/visorbus/visorchannel.c | 83 |
1 files changed, 71 insertions, 12 deletions
diff --git a/drivers/staging/unisys/visorbus/visorchannel.c b/drivers/staging/unisys/visorbus/visorchannel.c index 1bfbc06..0ddfe05 100644 --- a/drivers/staging/unisys/visorbus/visorchannel.c +++ b/drivers/staging/unisys/visorbus/visorchannel.c @@ -15,7 +15,7 @@ */ /* - * This provides Supervisor channel communication primitives, which are + * This provides s-Par channel communication primitives, which are * independent of the mechanism used to access the channel data. */ @@ -55,8 +55,28 @@ struct visorchannel { uuid_le inst; }; -/* Creates the struct visorchannel abstraction for a data area in memory, - * but does NOT modify this data area. +/** + * visorchannel_create_guts() - creates the struct visorchannel abstraction + * for a data area in memory, but does NOT modify + * this data area + * @physaddr: physical address of start of channel + * @channel_bytes: size of the channel in bytes; this may 0 if the channel has + * already been initialized in memory (which is true for all + * channels provided to guest environments by the s-Par + * back-end), in which case the actual channel size will be + * read from the channel header in memory + * @gfp: gfp_t to use when allocating memory for the data struct + * @guid: uuid that identifies channel type; this may 0 if the channel + * has already been initialized in memory (which is true for all + * channels provided to guest environments by the s-Par + * back-end), in which case the actual channel guid will be + * read from the channel header in memory + * @needs_lock: must specify true if you have multiple threads of execution + * that will be calling visorchannel methods of this + * visorchannel at the same time + * + * Return: pointer to visorchannel that was created if successful, + * otherwise NULL */ static struct visorchannel * visorchannel_create_guts(u64 physaddr, unsigned long channel_bytes, @@ -77,7 +97,8 @@ visorchannel_create_guts(u64 physaddr, unsigned long channel_bytes, spin_lock_init(&channel->insert_lock); spin_lock_init(&channel->remove_lock); - /* Video driver constains the efi framebuffer so it will get a + /* + * Video driver constains the efi framebuffer so it will get a * conflict resource when requesting its full mem region. Since * we are only using the efi framebuffer for video we can ignore * this. Remember that we haven't requested it so we don't try to @@ -214,6 +235,12 @@ visorchannel_set_clientpartition(struct visorchannel *channel, return 0; } +/** + * visorchannel_get_uuid() - queries the UUID of the designated channel + * @channel: the channel to query + * + * Return: the UUID of the provided channel + */ uuid_le visorchannel_get_uuid(struct visorchannel *channel) { @@ -260,22 +287,25 @@ visorchannel_get_header(struct visorchannel *channel) return (void __iomem *)&channel->chan_hdr; } -/** Return offset of a specific SIGNAL_QUEUE_HEADER from the beginning of a - * channel header +/* + * Return offset of a specific SIGNAL_QUEUE_HEADER from the beginning of a + * channel header */ #define SIG_QUEUE_OFFSET(chan_hdr, q) \ ((chan_hdr)->ch_space_offset + \ ((q) * sizeof(struct signal_queue_header))) -/** Return offset of a specific queue entry (data) from the beginning of a - * channel header +/* + * Return offset of a specific queue entry (data) from the beginning of a + * channel header */ #define SIG_DATA_OFFSET(chan_hdr, q, sig_hdr, slot) \ (SIG_QUEUE_OFFSET(chan_hdr, q) + (sig_hdr)->sig_base_offset + \ ((slot) * (sig_hdr)->signal_size)) -/** Write the contents of a specific field within a SIGNAL_QUEUE_HEADER back - * into host memory +/* + * Write the contents of a specific field within a SIGNAL_QUEUE_HEADER back + * into host memory */ #define SIG_WRITE_FIELD(channel, queue, sig_hdr, FIELD) \ (visorchannel_write(channel, \ @@ -350,7 +380,8 @@ signalremove_inner(struct visorchannel *channel, u32 queue, void *msg) return false; sig_hdr.num_received++; - /* For each data field in SIGNAL_QUEUE_HEADER that was modified, + /* + * For each data field in SIGNAL_QUEUE_HEADER that was modified, * update host memory. */ mb(); /* required for channel synch */ @@ -361,6 +392,15 @@ signalremove_inner(struct visorchannel *channel, u32 queue, void *msg) return true; } +/** + * visorchannel_signalremove() - removes a message from the designated + * channel/queue + * @channel: the channel the message will be removed from + * @queue: the queue the message will be removed from + * @msg: the message to remove + * + * Return: boolean indicating whether the removal succeeded or failed + */ bool visorchannel_signalremove(struct visorchannel *channel, u32 queue, void *msg) { @@ -379,6 +419,15 @@ visorchannel_signalremove(struct visorchannel *channel, u32 queue, void *msg) } EXPORT_SYMBOL_GPL(visorchannel_signalremove); +/** + * visorchannel_signalempty() - checks if the designated channel/queue + * contains any messages + * @channel: the channel to query + * @queue: the queue in the channel to query + * + * Return: boolean indicating whether any messages in the designated + * channel/queue are present + */ bool visorchannel_signalempty(struct visorchannel *channel, u32 queue) { @@ -425,7 +474,8 @@ signalinsert_inner(struct visorchannel *channel, u32 queue, void *msg) sig_hdr.num_sent++; - /* For each data field in SIGNAL_QUEUE_HEADER that was modified, + /* + * For each data field in SIGNAL_QUEUE_HEADER that was modified, * update host memory. */ mb(); /* required for channel synch */ @@ -437,6 +487,15 @@ signalinsert_inner(struct visorchannel *channel, u32 queue, void *msg) return true; } +/** + * visorchannel_signalinsert() - inserts a message into the designated + * channel/queue + * @channel: the channel the message will be added to + * @queue: the queue the message will be added to + * @msg: the message to insert + * + * Return: boolean indicating whether the insertion succeeded or failed + */ bool visorchannel_signalinsert(struct visorchannel *channel, u32 queue, void *msg) { |