diff options
| author | Mithlesh Thukral <mithlesh@linsyssoft.com> | 2009-01-19 20:23:22 +0530 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2009-04-03 14:53:10 -0700 |
| commit | d9d578bff771229c017582d746259ac282ee01e2 (patch) | |
| tree | d9ee56c1568acc1065d54c5554035521bf0bb6d1 /drivers/staging/sxg/sxghif.h | |
| parent | 371d7a9e6f0486fb814582c46785fdb147d7215e (diff) | |
Staging: sxg: SXG SGL related cleanup in data structures and code
* Cleanup in allocation of SXG_SGLs.
* Locking issues related to SglQLock.
* XmtCmd and XmtZeroLock consistency fixes.
Signed-off-by: LinSysSoft Sahara Team <saharaproj@linsyssoft.com>
Signed-off-by: Christopher Harrer <charrer@alacritech.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/staging/sxg/sxghif.h')
| -rw-r--r-- | drivers/staging/sxg/sxghif.h | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/drivers/staging/sxg/sxghif.h b/drivers/staging/sxg/sxghif.h index 5a9e2712c89..faba61529dd 100644 --- a/drivers/staging/sxg/sxghif.h +++ b/drivers/staging/sxg/sxghif.h @@ -486,6 +486,20 @@ struct sxg_ring_info { SXG_RING_ADVANCE_TAIL(_ringinfo); \ } +/* + * For a given ring find out how much the first pointer is ahead of + * the second pointer. "ahead" recognises the fact that the ring can wrap + */ +static inline int sxg_ring_get_forward_diff (struct sxg_ring_info *ringinfo, + int a, int b) { + if ((a < 0 || a > ringinfo->Size ) || (b < 0 || b > ringinfo->Size)) + return -1; + if (a > b) /* _a is lagging _b and _b has not wrapped around */ + return (a - b); + else + return ((ringinfo->Size - (b - a))); +} + /*************************************************************** * Host Command Buffer - commands to INIC via the Cmd Rings * |