staging: unisys: visorchannel some general function cleanups

Just some cleanups for visorchannel.c, and removal of
safe_sig_queue_validate() which is dead code.

Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Benjamin Romer <benjamin.romer@unisys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/unisys/visorbus/visorchannel.c b/drivers/staging/unisys/visorbus/visorchannel.c
index ff14a0d..30bedcc 100644 (file)
--- a/drivers/staging/unisys/visorbus/visorchannel.c
+++ b/drivers/staging/unisys/visorbus/visorchannel.c
@@ -211,13 +211,12 @@ int
 visorchannel_read(struct visorchannel *channel, ulong offset,
                  void *local, ulong nbytes)
 {
-       int rc = visor_memregion_read(channel->memregion, offset,
-                                     local, nbytes);
-       if ((rc >= 0) && (offset == 0) &&
-           (nbytes >= sizeof(struct channel_header))) {
-               memcpy(&channel->chan_hdr, local,
-                      sizeof(struct channel_header));
-       }
+       int rc;
+       size_t size = sizeof(struct channel_header);
+
+       rc = visor_memregion_read(channel->memregion, offset, local, nbytes);
+       if (rc && !offset && (nbytes >= size))
+               memcpy(&channel->chan_hdr, local, size);
        return rc;
 }
 EXPORT_SYMBOL_GPL(visorchannel_read);
@@ -226,9 +225,10 @@ int
 visorchannel_write(struct visorchannel *channel, ulong offset,
                   void *local, ulong nbytes)
 {
-       if (offset == 0 && nbytes >= sizeof(struct channel_header))
-               memcpy(&channel->chan_hdr, local,
-                      sizeof(struct channel_header));
+       size_t size = sizeof(struct channel_header);
+
+       if (!offset && nbytes >= size)
+               memcpy(&channel->chan_hdr, local, size);
        return visor_memregion_write(channel->memregion, offset, local, nbytes);
 }
 EXPORT_SYMBOL_GPL(visorchannel_write);
@@ -237,38 +237,34 @@ int
 visorchannel_clear(struct visorchannel *channel, ulong offset, u8 ch,
                   ulong nbytes)
 {
-       int rc = -1;
+       int err;
        int bufsize = 65536;
        int written = 0;
-       u8 *buf = vmalloc(bufsize);
+       u8 *buf;
 
+       buf = vmalloc(bufsize);
        if (!buf)
-               goto cleanup;
+               return -ENOMEM;
 
        memset(buf, ch, bufsize);
        while (nbytes > 0) {
                ulong thisbytes = bufsize;
-               int x = -1;
 
                if (nbytes < thisbytes)
                        thisbytes = nbytes;
-               x = visor_memregion_write(channel->memregion, offset + written,
-                                         buf, thisbytes);
-               if (x < 0) {
-                       rc = x;
+               err = visor_memregion_write(channel->memregion,
+                                           offset + written, buf, thisbytes);
+               if (err)
                        goto cleanup;
-               }
+
                written += thisbytes;
                nbytes -= thisbytes;
        }
-       rc = 0;
+       return 0;
 
 cleanup:
-       if (buf) {
-               vfree(buf);
-               buf = NULL;
-       }
-       return rc;
+       vfree(buf);
+       return err;
 }
 EXPORT_SYMBOL_GPL(visorchannel_clear);
 
@@ -307,22 +303,19 @@ static BOOL
 sig_read_header(struct visorchannel *channel, u32 queue,
                struct signal_queue_header *sig_hdr)
 {
-       BOOL rc = FALSE;
+       int err;
 
        if (channel->chan_hdr.ch_space_offset < sizeof(struct channel_header))
-               goto cleanup;
+               return FALSE;
 
        /* Read the appropriate SIGNAL_QUEUE_HEADER into local memory. */
+       err = visor_memregion_read(channel->memregion,
+                                  SIG_QUEUE_OFFSET(&channel->chan_hdr, queue),
+                                  sig_hdr, sizeof(struct signal_queue_header));
+       if (err)
+               return FALSE;
 
-       if (visor_memregion_read(channel->memregion,
-                                SIG_QUEUE_OFFSET(&channel->chan_hdr, queue),
-                                sig_hdr,
-                                sizeof(struct signal_queue_header)) < 0) {
-               goto cleanup;
-       }
-       rc = TRUE;
-cleanup:
-       return rc;
+       return TRUE;
 }
 
 static BOOL
@@ -330,24 +323,23 @@ sig_do_data(struct visorchannel *channel, u32 queue,
            struct signal_queue_header *sig_hdr, u32 slot, void *data,
            BOOL is_write)
 {
-       BOOL rc = FALSE;
+       int err;
        int signal_data_offset = SIG_DATA_OFFSET(&channel->chan_hdr, queue,
                                                 sig_hdr, slot);
        if (is_write) {
-               if (visor_memregion_write(channel->memregion,
-                                         signal_data_offset,
-                                         data, sig_hdr->signal_size) < 0) {
-                       goto cleanup;
-               }
+               err = visor_memregion_write(channel->memregion,
+                                           signal_data_offset,
+                                           data, sig_hdr->signal_size);
+               if (err)
+                       return FALSE;
        } else {
-               if (visor_memregion_read(channel->memregion, signal_data_offset,
-                                        data, sig_hdr->signal_size) < 0) {
-                       goto cleanup;
-               }
+               err = visor_memregion_read(channel->memregion,
+                                          signal_data_offset,
+                                          data, sig_hdr->signal_size);
+               if (err)
+                       return FALSE;
        }
-       rc = TRUE;
-cleanup:
-       return rc;
+       return TRUE;
 }
 
 static inline BOOL
@@ -364,26 +356,6 @@ sig_write_data(struct visorchannel *channel, u32 queue,
        return sig_do_data(channel, queue, sig_hdr, slot, data, TRUE);
 }
 
-static inline unsigned char
-safe_sig_queue_validate(struct signal_queue_header *psafe_sqh,
-                       struct signal_queue_header *punsafe_sqh,
-                       u32 *phead, u32 *ptail)
-{
-       if ((*phead >= psafe_sqh->max_slots) ||
-           (*ptail >= psafe_sqh->max_slots)) {
-               /* Choose 0 or max, maybe based on current tail value */
-               *phead = 0;
-               *ptail = 0;
-
-               /* Sync with client as necessary */
-               punsafe_sqh->head = *phead;
-               punsafe_sqh->tail = *ptail;
-
-               return 0;
-       }
-       return 1;
-}                              /* end safe_sig_queue_validate */
-
 static BOOL
 signalremove_inner(struct visorchannel *channel, u32 queue, void *msg)
 {