From 444b91868b5294e3a2151fffa3b063763a562448 Mon Sep 17 00:00:00 2001 From: Attilio Rao Date: Sun, 2 Aug 2009 14:28:40 +0000 Subject: Make the newbus subsystem Giant free by adding the new newbus sxlock. The newbus lock is responsible for protecting newbus internIal structures, device states and devclass flags. It is necessary to hold it when all such datas are accessed. For the other operations, softc locking should ensure enough protection to avoid races. Newbus lock is automatically held when virtual operations on the device and bus are invoked when loading the driver or when the suspend/resume take place. For other 'spourious' operations trying to access/modify the newbus topology, newbus lock needs to be automatically acquired and dropped. For the moment Giant is also acquired in some key point (modules subsystem) in order to avoid problems before the 8.0 release as module handlers could make assumptions about it. This Giant locking should go just after the release happens. Please keep in mind that the public interface can be expanded in order to provide more support, if there are really necessities at some point and also some bugs could arise as long as the patch needs a bit of further testing. Bump __FreeBSD_version in order to reflect the newbus lock introduction. Reviewed by: ed, hps, jhb, imp, mav, scottl No answer by: ariff, thompsa, yongari Tested by: pho, G. Trematerra , Brandon Gooch Sponsored by: Yahoo! Incorporated Approved by: re (ksmith) --- sys/dev/mfi/mfi.c | 20 +++++++++++++------- 1 file changed, 13 insertions(+), 7 deletions(-) (limited to 'sys/dev/mfi') diff --git a/sys/dev/mfi/mfi.c b/sys/dev/mfi/mfi.c index eb18ffe4ce35..0ae585e892df 100644 --- a/sys/dev/mfi/mfi.c +++ b/sys/dev/mfi/mfi.c @@ -1327,11 +1327,11 @@ mfi_add_ld_complete(struct mfi_command *cm) mfi_release_command(cm); mtx_unlock(&sc->mfi_io_lock); - mtx_lock(&Giant); + newbus_xlock(); if ((child = device_add_child(sc->mfi_dev, "mfid", -1)) == NULL) { device_printf(sc->mfi_dev, "Failed to add logical disk\n"); free(ld_info, M_MFIBUF); - mtx_unlock(&Giant); + newbus_xunlock(); mtx_lock(&sc->mfi_io_lock); return; } @@ -1339,7 +1339,7 @@ mfi_add_ld_complete(struct mfi_command *cm) device_set_ivars(child, ld_info); device_set_desc(child, "MFI Logical Disk"); bus_generic_attach(sc->mfi_dev); - mtx_unlock(&Giant); + newbus_xunlock(); mtx_lock(&sc->mfi_io_lock); } @@ -1805,9 +1805,9 @@ mfi_check_command_post(struct mfi_softc *sc, struct mfi_command *cm) KASSERT(ld != NULL, ("volume dissappeared")); if (cm->cm_frame->header.cmd_status == MFI_STAT_OK) { mtx_unlock(&sc->mfi_io_lock); - mtx_lock(&Giant); + newbus_xlock(); device_delete_child(sc->mfi_dev, ld->ld_dev); - mtx_unlock(&Giant); + newbus_xunlock(); mtx_lock(&sc->mfi_io_lock); } else mfi_disk_enable(ld); @@ -1815,11 +1815,11 @@ mfi_check_command_post(struct mfi_softc *sc, struct mfi_command *cm) case MFI_DCMD_CFG_CLEAR: if (cm->cm_frame->header.cmd_status == MFI_STAT_OK) { mtx_unlock(&sc->mfi_io_lock); - mtx_lock(&Giant); + newbus_xlock(); TAILQ_FOREACH_SAFE(ld, &sc->mfi_ld_tqh, ld_link, ldn) { device_delete_child(sc->mfi_dev, ld->ld_dev); } - mtx_unlock(&Giant); + newbus_xunlock(); mtx_lock(&sc->mfi_io_lock); } else { TAILQ_FOREACH(ld, &sc->mfi_ld_tqh, ld_link) @@ -1985,7 +1985,9 @@ mfi_ioctl(struct cdev *dev, u_long cmd, caddr_t arg, int flag, struct thread *td adapter = ioc->mfi_adapter_no; if (device_get_unit(sc->mfi_dev) == 0 && adapter != 0) { + newbus_slock(); devclass = devclass_find("mfi"); + newbus_sunlock(); sc = devclass_get_softc(devclass, adapter); } mtx_lock(&sc->mfi_io_lock); @@ -2173,7 +2175,9 @@ out: struct mfi_linux_ioc_packet l_ioc; int adapter; + newbus_slock(); devclass = devclass_find("mfi"); + newbus_sunlock(); if (devclass == NULL) return (ENOENT); @@ -2194,7 +2198,9 @@ out: struct mfi_linux_ioc_aen l_aen; int adapter; + newbus_slock(); devclass = devclass_find("mfi"); + newbus_sunlock(); if (devclass == NULL) return (ENOENT); -- cgit v1.3