diff options
Diffstat (limited to 'include/scsi')
| -rw-r--r-- | include/scsi/scsi.h | 19 | ||||
| -rw-r--r-- | include/scsi/scsi_host.h | 13 |
2 files changed, 19 insertions, 13 deletions
diff --git a/include/scsi/scsi.h b/include/scsi/scsi.h index 702fcfeb37f..0f55f5b2489 100644 --- a/include/scsi/scsi.h +++ b/include/scsi/scsi.h @@ -11,6 +11,25 @@ #include <linux/types.h> /* + * The maximum number of SG segments that we will put inside a + * scatterlist (unless chaining is used). Should ideally fit inside a + * single page, to avoid a higher order allocation. We could define this + * to SG_MAX_SINGLE_ALLOC to pack correctly at the highest order. The + * minimum value is 32 + */ +#define SCSI_MAX_SG_SEGMENTS 128 + +/* + * Like SCSI_MAX_SG_SEGMENTS, but for archs that have sg chaining. This limit + * is totally arbitrary, a setting of 2048 will get you at least 8mb ios. + */ +#ifdef ARCH_HAS_SG_CHAIN +#define SCSI_MAX_SG_CHAIN_SEGMENTS 2048 +#else +#define SCSI_MAX_SG_CHAIN_SEGMENTS SCSI_MAX_SG_SEGMENTS +#endif + +/* * SCSI command lengths */ diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h index cb2bcab41df..5c58d594126 100644 --- a/include/scsi/scsi_host.h +++ b/include/scsi/scsi_host.h @@ -39,9 +39,6 @@ struct blk_queue_tags; #define DISABLE_CLUSTERING 0 #define ENABLE_CLUSTERING 1 -#define DISABLE_SG_CHAINING 0 -#define ENABLE_SG_CHAINING 1 - enum scsi_eh_timer_return { EH_NOT_HANDLED, EH_HANDLED, @@ -446,15 +443,6 @@ struct scsi_host_template { unsigned ordered_tag:1; /* - * true if the low-level driver can support sg chaining. this - * will be removed eventually when all the drivers are - * converted to support sg chaining. - * - * Status: OBSOLETE - */ - unsigned use_sg_chaining:1; - - /* * Countdown for host blocking with no commands outstanding */ unsigned int max_host_blocked; @@ -598,7 +586,6 @@ struct Scsi_Host { unsigned unchecked_isa_dma:1; unsigned use_clustering:1; unsigned use_blk_tcq:1; - unsigned use_sg_chaining:1; /* * Host has requested that no further requests come through for the |