diff options
author | mjacob <mjacob@FreeBSD.org> | 2007-02-23 05:47:36 +0000 |
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committer | mjacob <mjacob@FreeBSD.org> | 2007-02-23 05:47:36 +0000 |
commit | 5688edd0032e2541fedeaa58a3f918aa0af73835 (patch) | |
tree | 50726cb63cfc4a82afc34c955a6de30d742f0611 /sys/cam/cam_xpt.c | |
parent | 17f2e510e6ae66722eeb73d65b12574eca7a9f3c (diff) | |
download | FreeBSD-src-5688edd0032e2541fedeaa58a3f918aa0af73835.zip FreeBSD-src-5688edd0032e2541fedeaa58a3f918aa0af73835.tar.gz |
Add an xpt_rescan function and a thread that will field
rescan requests. The purpose of this is to allow a SIM
(or other entities) to request a bus rescan and have it
then fielded in a different (process) context from the
caller.
There are probably better ways to accomplish this, but
it's a very small change that helps solve a number of
problems.
Reviewed by: Justin, Ken and Scott.
MFC after: 2 weeks
Diffstat (limited to 'sys/cam/cam_xpt.c')
-rw-r--r-- | sys/cam/cam_xpt.c | 53 |
1 files changed, 49 insertions, 4 deletions
diff --git a/sys/cam/cam_xpt.c b/sys/cam/cam_xpt.c index 2b1c8f4..ba6eefb 100644 --- a/sys/cam/cam_xpt.c +++ b/sys/cam/cam_xpt.c @@ -46,6 +46,7 @@ __FBSDID("$FreeBSD$"); #include <sys/lock.h> #include <sys/mutex.h> #include <sys/sysctl.h> +#include <sys/kthread.h> #ifdef PC98 #include <pc98/pc98/pc98_machdep.h> /* geometry translation */ @@ -1412,10 +1413,50 @@ cam_module_event_handler(module_t mod, int what, void *arg) return 0; } +/* thread to handle bus rescans */ +static TAILQ_HEAD(, ccb_hdr) ccb_scanq; +static void +xpt_scanner_thread(void *dummy) +{ + mtx_lock(&Giant); + for (;;) { + union ccb *ccb; + tsleep(&ccb_scanq, PRIBIO, "ccb_scanq", 0); + while ((ccb = (union ccb *)TAILQ_FIRST(&ccb_scanq)) != NULL) { + TAILQ_REMOVE(&ccb_scanq, &ccb->ccb_h, sim_links.tqe); + ccb->ccb_h.func_code = XPT_SCAN_BUS; + ccb->ccb_h.cbfcnp = xptdone; + xpt_setup_ccb(&ccb->ccb_h, ccb->ccb_h.path, 5); + cam_periph_runccb(ccb, NULL, 0, 0, NULL); + xpt_free_path(ccb->ccb_h.path); + xpt_free_ccb(ccb); + } + } +} + +void +xpt_rescan(union ccb *ccb) +{ + struct ccb_hdr *hdr; + GIANT_REQUIRED; + /* + * Don't make duplicate entries for the same paths. + */ + TAILQ_FOREACH(hdr, &ccb_scanq, sim_links.tqe) { + if (xpt_path_comp(hdr->path, ccb->ccb_h.path) == 0) { + xpt_print(ccb->ccb_h.path, "rescan already queued\n"); + xpt_free_path(ccb->ccb_h.path); + xpt_free_ccb(ccb); + return; + } + } + TAILQ_INSERT_TAIL(&ccb_scanq, &ccb->ccb_h, sim_links.tqe); + wakeup(&ccb_scanq); +} + /* Functions accessed by the peripheral drivers */ static void -xpt_init(dummy) - void *dummy; +xpt_init(void *dummy) { struct cam_sim *xpt_sim; struct cam_path *path; @@ -1425,6 +1466,7 @@ xpt_init(dummy) TAILQ_INIT(&xpt_busses); TAILQ_INIT(&cam_bioq); SLIST_INIT(&ccb_freeq); + TAILQ_INIT(&ccb_scanq); STAILQ_INIT(&highpowerq); mtx_init(&cam_bioq_lock, "CAM BIOQ lock", NULL, MTX_DEF); @@ -1490,6 +1532,10 @@ xpt_init(dummy) "- failing attach\n"); } + /* fire up rescan thread */ + if (kthread_create(xpt_scanner_thread, NULL, NULL, 0, 0, "xpt_thrd")) { + printf("xpt_init: failed to create rescan thread\n"); + } /* Install our software interrupt handlers */ swi_add(NULL, "cambio", camisr, &cam_bioq, SWI_CAMBIO, 0, &cambio_ih); } @@ -4453,8 +4499,7 @@ xptnextfreepathid(void) bus = TAILQ_FIRST(&xpt_busses); retry: /* Find an unoccupied pathid */ - while (bus != NULL - && bus->path_id <= pathid) { + while (bus != NULL && bus->path_id <= pathid) { if (bus->path_id == pathid) pathid++; bus = TAILQ_NEXT(bus, links); |