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Diffstat (limited to 'Documentation/block/request.txt')
| -rw-r--r-- | Documentation/block/request.txt | 88 |
1 files changed, 0 insertions, 88 deletions
diff --git a/Documentation/block/request.txt b/Documentation/block/request.txt deleted file mode 100644 index 754e104ed369..000000000000 --- a/Documentation/block/request.txt +++ /dev/null @@ -1,88 +0,0 @@ - -struct request documentation - -Jens Axboe <jens.axboe@oracle.com> 27/05/02 - -1.0 -Index - -2.0 Struct request members classification - - 2.1 struct request members explanation - -3.0 - - -2.0 -Short explanation of request members - -Classification flags: - - D driver member - B block layer member - I I/O scheduler member - -Unless an entry contains a D classification, a device driver must not access -this member. Some members may contain D classifications, but should only be -access through certain macros or functions (eg ->flags). - -<linux/blkdev.h> - -2.1 -Member Flag Comment ------- ---- ------- - -struct list_head queuelist BI Organization on various internal - queues - -void *elevator_private I I/O scheduler private data - -unsigned char cmd[16] D Driver can use this for setting up - a cdb before execution, see - blk_queue_prep_rq - -unsigned long flags DBI Contains info about data direction, - request type, etc. - -int rq_status D Request status bits - -kdev_t rq_dev DBI Target device - -int errors DB Error counts - -sector_t sector DBI Target location - -unsigned long hard_nr_sectors B Used to keep sector sane - -unsigned long nr_sectors DBI Total number of sectors in request - -unsigned long hard_nr_sectors B Used to keep nr_sectors sane - -unsigned short nr_phys_segments DB Number of physical scatter gather - segments in a request - -unsigned short nr_hw_segments DB Number of hardware scatter gather - segments in a request - -unsigned int current_nr_sectors DB Number of sectors in first segment - of request - -unsigned int hard_cur_sectors B Used to keep current_nr_sectors sane - -int tag DB TCQ tag, if assigned - -void *special D Free to be used by driver - -char *buffer D Map of first segment, also see - section on bouncing SECTION - -struct completion *waiting D Can be used by driver to get signalled - on request completion - -struct bio *bio DBI First bio in request - -struct bio *biotail DBI Last bio in request - -struct request_queue *q DB Request queue this request belongs to - -struct request_list *rl B Request list this request came from |