db3b5848ea
__cfq_get_queue(). __cfq_get_queue() finds an existing queue (struct cfq_queue) of the current process for the device and returns it. If it's not found, __cfq_get_queue() creates and returns a new one if __cfq_get_queue() is called with __GFP_WAIT flag, or __cfq_get_queue() returns NULL (this means that get_request() fails) if no __GFP_WAIT flag. On the other hand, in __make_request(), get_request() is called without __GFP_WAIT flag at the first time. Thus, the get_request() fails when there is no existing queue, typically when it's called for the first I/O request of the process to the device. Though it will be followed by get_request_wait() for general case, __make_request() will just end the I/O with an error (EWOULDBLOCK) when the request was for read-ahead. Signed-off-by: Jens Axboe <axboe@suse.de> Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com> Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com> |
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| .. | ||
| aoe | ||
| paride | ||
| DAC960.c | ||
| DAC960.h | ||
| Kconfig | ||
| Kconfig.iosched | ||
| Makefile | ||
| acsi.c | ||
| acsi_slm.c | ||
| amiflop.c | ||
| as-iosched.c | ||
| ataflop.c | ||
| cciss.c | ||
| cciss.h | ||
| cciss_cmd.h | ||
| cciss_scsi.c | ||
| cciss_scsi.h | ||
| cfq-iosched.c | ||
| cpqarray.c | ||
| cpqarray.h | ||
| cryptoloop.c | ||
| deadline-iosched.c | ||
| elevator.c | ||
| floppy.c | ||
| genhd.c | ||
| ida_cmd.h | ||
| ida_ioctl.h | ||
| ioctl.c | ||
| ll_rw_blk.c | ||
| loop.c | ||
| nbd.c | ||
| noop-iosched.c | ||
| pktcdvd.c | ||
| ps2esdi.c | ||
| rd.c | ||
| scsi_ioctl.c | ||
| smart1,2.h | ||
| swim3.c | ||
| swim_iop.c | ||
| sx8.c | ||
| ub.c | ||
| umem.c | ||
| viodasd.c | ||
| xd.c | ||
| xd.h | ||
| z2ram.c | ||