On Thu, 29 Sep 2005, Jeff Garzik wrote: > Joshua Kwan wrote: > > Hello, > > > > I had some time yesterday and decided to help Jens out by rediffing the > > now-infamous SATA suspend-to-ram patch [1] against current git and > > test-building it. > > > > For posterity, > > > > This patch adds the ata_scsi_device_resume and ata_scsi_device_suspend > > functions (along with helpers) to put to sleep and wake up Serial ATA > > controllers when entering sleep states, and hooks the functions into > > each SATA controller driver so that suspend-to-RAM is possible. > > > > Note that this patch is a holdover patch until it is possible to > > generalize this concept for all SCSI devices, which requires more data > > on which devices need to be put to sleep and which don't. > > > > Signed-off-by: Joshua Kwan <joshk@xxxxxxxxxxxxxxx> > > Ah hah! I found the other SCSI suspend patch: > > http://lwn.net/Articles/97453/ > > Anybody (Joshua?) up for reconciling and testing the two? > > The main change from Jens/Joshua's patch is that we use SCSI's > sd_shutdown() to call sync cache, eliminating the need for > ata_flush_cache(), since the SCSI layer would now perform that. > > For bonus points, > > 1) sd should call START STOP UNIT on suspend, which eliminates the need > for ata_standby_drive(), and completely encompasses the suspend process > in the SCSI layer. > > 2) sd should call START STOP UNIT on resume -- and as a SUPER BONUS, the > combination of these two changes ensures that there are no queue > synchronization issues, the likes of which would require hacks like > Jens' while-loop patch. > > None of these are huge changes requiring a lot of thinking/planning... > > Finally, ideally, we should be issuing a hardware or software reset on > suspend. Here's Nathan Bryant's patch (from the lwn.ne article) updated to 2.6.14-rc2-git7 + changes that Christoph suggested (except that 'scsi_device_resume' name was already used, so I changed it to 'scsi_device_wakeup' instead). I'll get back to Jeff's suggestion(s) and the sysfs flag next, but others can use this as a basis if wanted. (also available from http://www.xenotime.net/linux/scsi/scsi-suspend-resume.patch ) -- ~Randy drivers/scsi/scsi_priv.h | 2 + drivers/scsi/scsi_sysfs.c | 39 +++++++++++++++++++++++++++++++++-- drivers/scsi/sd.c | 18 +++++++++++++++- include/scsi/scsi_driver.h | 2 + 4 files changed, 58 insertions(+), 3 deletions(-) diff -Naurp -X linux-2614-rc2/Documentation/dontdiff linux-2614-rc2-git7-clean/drivers/scsi/scsi_priv.h linux-2614-rc2-git7-scsi/drivers/scsi/scsi_priv.h --- linux-2614-rc2-git7-clean/drivers/scsi/scsi_priv.h 2005-09-29 12:58:21.000000000 -0700 +++ linux-2614-rc2-git7-scsi/drivers/scsi/scsi_priv.h 2005-09-29 12:48:00.000000000 -0700 @@ -55,6 +55,8 @@ static inline void scsi_log_send(struct static inline void scsi_log_completion(struct scsi_cmnd *cmd, int disposition) { }; #endif +extern int scsi_device_suspend(struct device *dev, pm_message_t state); +extern int scsi_device_wakeup(struct device *dev); /* scsi_devinfo.c */ extern int scsi_get_device_flags(struct scsi_device *sdev, diff -Naurp -X linux-2614-rc2/Documentation/dontdiff linux-2614-rc2-git7-clean/drivers/scsi/scsi_sysfs.c linux-2614-rc2-git7-scsi/drivers/scsi/scsi_sysfs.c --- linux-2614-rc2-git7-clean/drivers/scsi/scsi_sysfs.c 2005-09-29 12:58:25.000000000 -0700 +++ linux-2614-rc2-git7-scsi/drivers/scsi/scsi_sysfs.c 2005-09-29 12:56:16.000000000 -0700 @@ -14,6 +14,7 @@ #include <scsi/scsi.h> #include <scsi/scsi_device.h> +#include <scsi/scsi_driver.h> #include <scsi/scsi_host.h> #include <scsi/scsi_tcq.h> #include <scsi/scsi_transport.h> @@ -264,8 +265,10 @@ static int scsi_bus_match(struct device } struct bus_type scsi_bus_type = { - .name = "scsi", - .match = scsi_bus_match, + .name = "scsi", + .match = scsi_bus_match, + .suspend = scsi_device_suspend, + .resume = scsi_device_wakeup, }; int scsi_sysfs_register(void) @@ -770,6 +773,38 @@ void scsi_remove_target(struct device *d } EXPORT_SYMBOL(scsi_remove_target); +int scsi_device_suspend(struct device *dev, pm_message_t state) +{ + int err; + struct scsi_device *sdev = to_scsi_device(dev); + struct scsi_driver *drv = to_scsi_driver(dev->driver); + + err = scsi_device_quiesce(sdev); + if (err) + return err; + + if (drv->suspend) + return drv->suspend(dev, state); + + return 0; +} + +int scsi_device_wakeup(struct device *dev) +{ + int err; + struct scsi_device *sdev = to_scsi_device(dev); + struct scsi_driver *drv = to_scsi_driver(dev->driver); + + if (drv->resume) { + err = drv->resume(dev); + if (err) + return err; + } + + scsi_device_resume(sdev); + return 0; +} + int scsi_register_driver(struct device_driver *drv) { drv->bus = &scsi_bus_type; diff -Naurp -X linux-2614-rc2/Documentation/dontdiff linux-2614-rc2-git7-clean/drivers/scsi/sd.c linux-2614-rc2-git7-scsi/drivers/scsi/sd.c --- linux-2614-rc2-git7-clean/drivers/scsi/sd.c 2005-09-29 12:58:25.000000000 -0700 +++ linux-2614-rc2-git7-scsi/drivers/scsi/sd.c 2005-09-29 13:02:10.000000000 -0700 @@ -117,6 +117,8 @@ static void sd_rw_intr(struct scsi_cmnd static int sd_probe(struct device *); static int sd_remove(struct device *); +static int sd_suspend(struct device *, pm_message_t); +static int sd_resume(struct device *); static void sd_shutdown(struct device *dev); static void sd_rescan(struct device *); static int sd_init_command(struct scsi_cmnd *); @@ -136,6 +138,8 @@ static struct scsi_driver sd_template = }, .rescan = sd_rescan, .init_command = sd_init_command, + .suspend = sd_suspend, + .resume = sd_resume, .issue_flush = sd_issue_flush, .prepare_flush = sd_prepare_flush, .end_flush = sd_end_flush, @@ -1691,7 +1695,19 @@ static void sd_shutdown(struct device *d printk(KERN_NOTICE "Synchronizing SCSI cache for disk %s: \n", sdkp->disk->disk_name); sd_sync_cache(sdp); -} +} + +static int sd_suspend(struct device *dev, pm_message_t state) +{ + sd_shutdown(dev); + return 0; +} + +static int sd_resume(struct device *dev) +{ + sd_rescan(dev); + return 0; +} /** * init_sd - entry point for this driver (both when built in or when diff -Naurp -X linux-2614-rc2/Documentation/dontdiff linux-2614-rc2-git7-clean/include/scsi/scsi_driver.h linux-2614-rc2-git7-scsi/include/scsi/scsi_driver.h --- linux-2614-rc2-git7-clean/include/scsi/scsi_driver.h 2005-08-28 16:41:01.000000000 -0700 +++ linux-2614-rc2-git7-scsi/include/scsi/scsi_driver.h 2005-09-29 12:47:43.000000000 -0700 @@ -13,6 +13,8 @@ struct scsi_driver { int (*init_command)(struct scsi_cmnd *); void (*rescan)(struct device *); + int (*suspend)(struct device *dev, pm_message_t state); + int (*resume)(struct device *dev); int (*issue_flush)(struct device *, sector_t *); int (*prepare_flush)(struct request_queue *, struct request *); void (*end_flush)(struct request_queue *, struct request *); - : send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
