Messages in this thread Patch in this message |  | | Date | Wed, 7 Jun 2006 20:22:23 -0700 | From | "Randy.Dunlap" <> | Subject | [PATCH] ide-cd: use blk_get_request() |
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On Wed, 7 Jun 2006 08:22:08 +0200 Jens Axboe wrote:
> On Tue, Jun 06 2006, Andrew Morton wrote: > > > > Note that Laurent is also passing through ide_cdrom_packet(), which has a > > `struct request' on the stack. The kernel does this in a lot of places, > > and at 168 bytes on x86, it'd really be best if we were to dynamically > > allocate these things. > > That's an old peeve of mine, on-stack requests... It's nasty from > several angles, stack usage just being one of them. Perhaps I'll give it > a go for 2.6.18 and add checks for request being thrown at the block > layer which didn't originate from get_request().
This is a start at converting ide-cd.c to use blk_get_request(). How does it look so far? It builds, but I have not tested it yet. And of course, there are other drivers to be modified as well.
--- From: Randy Dunlap <rdunlap@xenotime.net>
Convert struct request req; on function stacks to use allocation via blk_get_request() to (a) reduce stack pressure and (b) use centralized blk_ functions and (c) allow for block IO tracing.
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> --- drivers/ide/ide-cd.c | 258 +++++++++++++++++++++++++++++++++------------------ 1 files changed, 170 insertions(+), 88 deletions(-)
--- linux-2617-rc6.orig/drivers/ide/ide-cd.c +++ linux-2617-rc6/drivers/ide/ide-cd.c @@ -2033,24 +2033,32 @@ int msf_to_lba (byte m, byte s, byte f) static int cdrom_check_status(ide_drive_t *drive, struct request_sense *sense) { - struct request req; + struct request *req; struct cdrom_info *info = drive->driver_data; struct cdrom_device_info *cdi = &info->devinfo; + request_queue_t *q = cdi->disk->queue; + int stat; - cdrom_prepare_request(drive, &req); - - req.sense = sense; - req.cmd[0] = GPCMD_TEST_UNIT_READY; - req.flags |= REQ_QUIET; + req = blk_get_request(q, READ, GFP_KERNEL); + if (!req) + return -ENOMEM; + + cdrom_prepare_request(drive, req); + + req->sense = sense; + req->cmd[0] = GPCMD_TEST_UNIT_READY; + req->flags |= REQ_QUIET; #if ! STANDARD_ATAPI /* the Sanyo 3 CD changer uses byte 7 of TEST_UNIT_READY to switch CDs instead of supporting the LOAD_UNLOAD opcode */ - req.cmd[7] = cdi->sanyo_slot % 3; + req->cmd[7] = cdi->sanyo_slot % 3; #endif /* not STANDARD_ATAPI */ - return cdrom_queue_packet_command(drive, &req); + stat = cdrom_queue_packet_command(drive, req); + blk_put_request(req); + return stat; } @@ -2059,7 +2067,7 @@ static int cdrom_lockdoor(ide_drive_t *drive, int lockflag, struct request_sense *sense) { struct request_sense my_sense; - struct request req; + struct request *req; int stat; if (sense == NULL) @@ -2069,11 +2077,19 @@ cdrom_lockdoor(ide_drive_t *drive, int l if (CDROM_CONFIG_FLAGS(drive)->no_doorlock) { stat = 0; } else { - cdrom_prepare_request(drive, &req); - req.sense = sense; - req.cmd[0] = GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL; - req.cmd[4] = lockflag ? 1 : 0; - stat = cdrom_queue_packet_command(drive, &req); + struct cdrom_info *info = drive->driver_data; + struct cdrom_device_info *cdi = &info->devinfo; + request_queue_t *q = cdi->disk->queue; + + req = blk_get_request(q, WRITE, GFP_KERNEL); + if (!req) + return -ENOMEM; + cdrom_prepare_request(drive, req); + req->sense = sense; + req->cmd[0] = GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL; + req->cmd[4] = lockflag ? 1 : 0; + stat = cdrom_queue_packet_command(drive, req); + blk_put_request(req); } /* If we got an illegal field error, the drive @@ -2086,7 +2102,7 @@ cdrom_lockdoor(ide_drive_t *drive, int l CDROM_CONFIG_FLAGS(drive)->no_doorlock = 1; stat = 0; } - + /* no medium, that's alright. */ if (stat != 0 && sense->sense_key == NOT_READY && sense->asc == 0x3a) stat = 0; @@ -2103,26 +2119,36 @@ cdrom_lockdoor(ide_drive_t *drive, int l static int cdrom_eject(ide_drive_t *drive, int ejectflag, struct request_sense *sense) { - struct request req; + struct request *req; char loej = 0x02; + struct cdrom_info *info = drive->driver_data; + struct cdrom_device_info *cdi = &info->devinfo; + request_queue_t *q = cdi->disk->queue; + int stat; if (CDROM_CONFIG_FLAGS(drive)->no_eject && !ejectflag) return -EDRIVE_CANT_DO_THIS; - + /* reload fails on some drives, if the tray is locked */ if (CDROM_STATE_FLAGS(drive)->door_locked && ejectflag) return 0; - cdrom_prepare_request(drive, &req); + req = blk_get_request(q, WRITE, GFP_KERNEL); + if (!req) + return -ENOMEM; + cdrom_prepare_request(drive, req); /* only tell drive to close tray if open, if it can do that */ if (ejectflag && !CDROM_CONFIG_FLAGS(drive)->close_tray) loej = 0; - req.sense = sense; - req.cmd[0] = GPCMD_START_STOP_UNIT; - req.cmd[4] = loej | (ejectflag != 0); - return cdrom_queue_packet_command(drive, &req); + req->sense = sense; + req->cmd[0] = GPCMD_START_STOP_UNIT; + req->cmd[4] = loej | (ejectflag != 0); + stat = cdrom_queue_packet_command(drive, req); + + blk_put_request(req); + return stat; } static int cdrom_read_capacity(ide_drive_t *drive, unsigned long *capacity, @@ -2135,17 +2161,24 @@ static int cdrom_read_capacity(ide_drive } capbuf; int stat; - struct request req; - - cdrom_prepare_request(drive, &req); + struct request *req; + struct cdrom_info *info = drive->driver_data; + struct cdrom_device_info *cdi = &info->devinfo; + request_queue_t *q = cdi->disk->queue; - req.sense = sense; - req.cmd[0] = GPCMD_READ_CDVD_CAPACITY; - req.data = (char *)&capbuf; - req.data_len = sizeof(capbuf); - req.flags |= REQ_QUIET; + req = blk_get_request(q, READ, GFP_KERNEL); + if (!req) + return -ENOMEM; + cdrom_prepare_request(drive, req); + + req->sense = sense; + req->cmd[0] = GPCMD_READ_CDVD_CAPACITY; + req->data = (char *)&capbuf; + req->data_len = sizeof(capbuf); + req->flags |= REQ_QUIET; - stat = cdrom_queue_packet_command(drive, &req); + stat = cdrom_queue_packet_command(drive, req); + blk_put_request(req); if (stat == 0) { *capacity = 1 + be32_to_cpu(capbuf.lba); *sectors_per_frame = @@ -2159,24 +2192,33 @@ static int cdrom_read_tocentry(ide_drive int format, char *buf, int buflen, struct request_sense *sense) { - struct request req; - - cdrom_prepare_request(drive, &req); + struct request *req; + struct cdrom_info *info = drive->driver_data; + struct cdrom_device_info *cdi = &info->devinfo; + request_queue_t *q = cdi->disk->queue; + int stat; - req.sense = sense; - req.data = buf; - req.data_len = buflen; - req.flags |= REQ_QUIET; - req.cmd[0] = GPCMD_READ_TOC_PMA_ATIP; - req.cmd[6] = trackno; - req.cmd[7] = (buflen >> 8); - req.cmd[8] = (buflen & 0xff); - req.cmd[9] = (format << 6); + req = blk_get_request(q, READ, GFP_KERNEL); + if (!req) + return -ENOMEM; + cdrom_prepare_request(drive, req); + + req->sense = sense; + req->data = buf; + req->data_len = buflen; + req->flags |= REQ_QUIET; + req->cmd[0] = GPCMD_READ_TOC_PMA_ATIP; + req->cmd[6] = trackno; + req->cmd[7] = (buflen >> 8); + req->cmd[8] = (buflen & 0xff); + req->cmd[9] = (format << 6); if (msf_flag) - req.cmd[1] = 2; + req->cmd[1] = 2; - return cdrom_queue_packet_command(drive, &req); + stat = cdrom_queue_packet_command(drive, req); + blk_put_request(req); + return stat; } @@ -2352,20 +2394,30 @@ static int cdrom_read_toc(ide_drive_t *d static int cdrom_read_subchannel(ide_drive_t *drive, int format, char *buf, int buflen, struct request_sense *sense) { - struct request req; + struct request *req; + struct cdrom_info *info = drive->driver_data; + struct cdrom_device_info *cdi = &info->devinfo; + request_queue_t *q = cdi->disk->queue; + int stat; - cdrom_prepare_request(drive, &req); + req = blk_get_request(q, READ, GFP_KERNEL); + if (!req) + return -ENOMEM; + cdrom_prepare_request(drive, req); + + req->sense = sense; + req->data = buf; + req->data_len = buflen; + req->cmd[0] = GPCMD_READ_SUBCHANNEL; + req->cmd[1] = 2; /* MSF addressing */ + req->cmd[2] = 0x40; /* request subQ data */ + req->cmd[3] = format; + req->cmd[7] = (buflen >> 8); + req->cmd[8] = (buflen & 0xff); - req.sense = sense; - req.data = buf; - req.data_len = buflen; - req.cmd[0] = GPCMD_READ_SUBCHANNEL; - req.cmd[1] = 2; /* MSF addressing */ - req.cmd[2] = 0x40; /* request subQ data */ - req.cmd[3] = format; - req.cmd[7] = (buflen >> 8); - req.cmd[8] = (buflen & 0xff); - return cdrom_queue_packet_command(drive, &req); + stat = cdrom_queue_packet_command(drive, req); + blk_put_request(req); + return stat; } /* ATAPI cdrom drives are free to select the speed you request or any slower @@ -2373,45 +2425,64 @@ static int cdrom_read_subchannel(ide_dri static int cdrom_select_speed(ide_drive_t *drive, int speed, struct request_sense *sense) { - struct request req; - cdrom_prepare_request(drive, &req); + struct request *req; + struct cdrom_info *info = drive->driver_data; + struct cdrom_device_info *cdi = &info->devinfo; + request_queue_t *q = cdi->disk->queue; + int stat; + + req = blk_get_request(q, WRITE, GFP_KERNEL); + if (!req) + return -ENOMEM; + cdrom_prepare_request(drive, req); - req.sense = sense; + req->sense = sense; if (speed == 0) speed = 0xffff; /* set to max */ else speed *= 177; /* Nx to kbytes/s */ - req.cmd[0] = GPCMD_SET_SPEED; + req->cmd[0] = GPCMD_SET_SPEED; /* Read Drive speed in kbytes/second MSB */ - req.cmd[2] = (speed >> 8) & 0xff; + req->cmd[2] = (speed >> 8) & 0xff; /* Read Drive speed in kbytes/second LSB */ - req.cmd[3] = speed & 0xff; + req->cmd[3] = speed & 0xff; if (CDROM_CONFIG_FLAGS(drive)->cd_r || CDROM_CONFIG_FLAGS(drive)->cd_rw || CDROM_CONFIG_FLAGS(drive)->dvd_r) { /* Write Drive speed in kbytes/second MSB */ - req.cmd[4] = (speed >> 8) & 0xff; + req->cmd[4] = (speed >> 8) & 0xff; /* Write Drive speed in kbytes/second LSB */ - req.cmd[5] = speed & 0xff; + req->cmd[5] = speed & 0xff; } - return cdrom_queue_packet_command(drive, &req); + stat = cdrom_queue_packet_command(drive, req); + blk_put_request(req); + return stat; } static int cdrom_play_audio(ide_drive_t *drive, int lba_start, int lba_end) { struct request_sense sense; - struct request req; - - cdrom_prepare_request(drive, &req); + struct request *req; + struct cdrom_info *info = drive->driver_data; + struct cdrom_device_info *cdi = &info->devinfo; + request_queue_t *q = cdi->disk->queue; + int stat; - req.sense = &sense; - req.cmd[0] = GPCMD_PLAY_AUDIO_MSF; - lba_to_msf(lba_start, &req.cmd[3], &req.cmd[4], &req.cmd[5]); - lba_to_msf(lba_end-1, &req.cmd[6], &req.cmd[7], &req.cmd[8]); + req = blk_get_request(q, READ, GFP_KERNEL); + if (!req) + return -ENOMEM; + cdrom_prepare_request(drive, req); + + req->sense = &sense; + req->cmd[0] = GPCMD_PLAY_AUDIO_MSF; + lba_to_msf(lba_start, &req->cmd[3], &req->cmd[4], &req->cmd[5]); + lba_to_msf(lba_end-1, &req->cmd[6], &req->cmd[7], &req->cmd[8]); - return cdrom_queue_packet_command(drive, &req); + stat = cdrom_queue_packet_command(drive, req); + blk_put_request(req); + return stat; } static int cdrom_get_toc_entry(ide_drive_t *drive, int track, @@ -2445,8 +2516,9 @@ static int cdrom_get_toc_entry(ide_drive static int ide_cdrom_packet(struct cdrom_device_info *cdi, struct packet_command *cgc) { - struct request req; + struct request *req; ide_drive_t *drive = cdi->handle; + request_queue_t *q = cdi->disk->queue; if (cgc->timeout <= 0) cgc->timeout = ATAPI_WAIT_PC; @@ -2454,21 +2526,26 @@ static int ide_cdrom_packet(struct cdrom /* here we queue the commands from the uniform CD-ROM layer. the packet must be complete, as we do not touch it at all. */ - cdrom_prepare_request(drive, &req); - memcpy(req.cmd, cgc->cmd, CDROM_PACKET_SIZE); + req = blk_get_request(q, READ, GFP_KERNEL); + if (!req) + return -ENOMEM; + cdrom_prepare_request(drive, req); + memcpy(req->cmd, cgc->cmd, CDROM_PACKET_SIZE); if (cgc->sense) memset(cgc->sense, 0, sizeof(struct request_sense)); - req.data = cgc->buffer; - req.data_len = cgc->buflen; - req.timeout = cgc->timeout; + req->data = cgc->buffer; + req->data_len = cgc->buflen; + req->timeout = cgc->timeout; if (cgc->quiet) - req.flags |= REQ_QUIET; + req->flags |= REQ_QUIET; + + req->sense = cgc->sense; + cgc->stat = cdrom_queue_packet_command(drive, req); + blk_put_request(req); - req.sense = cgc->sense; - cgc->stat = cdrom_queue_packet_command(drive, &req); if (!cgc->stat) - cgc->buflen -= req.data_len; + cgc->buflen -= req->data_len; return cgc->stat; } @@ -2557,12 +2634,17 @@ int ide_cdrom_reset (struct cdrom_device { ide_drive_t *drive = cdi->handle; struct request_sense sense; - struct request req; + struct request *req; int ret; + request_queue_t *q = cdi->disk->queue; - cdrom_prepare_request(drive, &req); - req.flags = REQ_SPECIAL | REQ_QUIET; - ret = ide_do_drive_cmd(drive, &req, ide_wait); + req = blk_get_request(q, WRITE, GFP_KERNEL); + if (!req) + return -ENOMEM; + cdrom_prepare_request(drive, req); + req->flags = REQ_SPECIAL | REQ_QUIET; + ret = ide_do_drive_cmd(drive, req, ide_wait); + blk_put_request(req); /* * A reset will unlock the door. 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