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diff --git a/Documentation/block/request.rst b/Documentation/block/request.rst deleted file mode 100644 index 747021e1ffdb..000000000000 --- a/Documentation/block/request.rst +++ /dev/null @@ -1,99 +0,0 @@ -============================ -struct request documentation -============================ - -Jens Axboe <jens.axboe@oracle.com> 27/05/02 - - -.. FIXME: - No idea about what does mean - seems just some noise, so comment it - - 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> - -=============================== ======= ======================================= -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 -=============================== ======= ======================================= |