diff options
Diffstat (limited to 'freebsd/sys/kern/subr_bus.c')
| -rw-r--r-- | freebsd/sys/kern/subr_bus.c | 133 |
1 files changed, 101 insertions, 32 deletions
diff --git a/freebsd/sys/kern/subr_bus.c b/freebsd/sys/kern/subr_bus.c index 0626ec0a..391b2ed6 100644 --- a/freebsd/sys/kern/subr_bus.c +++ b/freebsd/sys/kern/subr_bus.c @@ -53,6 +53,7 @@ __FBSDID("$FreeBSD$"); #include <machine/bus.h> #include <sys/random.h> #include <sys/rman.h> +#include <sys/sbuf.h> #include <sys/selinfo.h> #include <sys/signalvar.h> #include <sys/smp.h> @@ -60,7 +61,6 @@ __FBSDID("$FreeBSD$"); #include <sys/systm.h> #include <sys/uio.h> #include <sys/bus.h> -#include <sys/interrupt.h> #include <sys/cpuset.h> #include <net/vnet.h> @@ -84,6 +84,8 @@ struct driverlink { kobj_class_t driver; TAILQ_ENTRY(driverlink) link; /* list of drivers in devclass */ int pass; + int flags; +#define DL_DEFERRED_PROBE 1 /* Probe deferred on this */ TAILQ_ENTRY(driverlink) passlink; }; @@ -155,6 +157,9 @@ EVENTHANDLER_LIST_DEFINE(device_detach); EVENTHANDLER_LIST_DEFINE(dev_lookup); static void devctl2_init(void); +static bool device_frozen; +#else /* __rtems__ */ +#define device_frozen false #endif /* __rtems__ */ #define DRIVERNAME(d) ((d)? d->name : "no driver") @@ -885,27 +890,18 @@ sysctl_devctl_queue(SYSCTL_HANDLER_ARGS) * Strings are always terminated with a NUL, but may be truncated if longer * than @p len bytes after quotes. * - * @param dst Buffer to hold the string. Must be at least @p len bytes long + * @param sb sbuf to place the characters into * @param src Original buffer. - * @param len Length of buffer pointed to by @dst, including trailing NUL */ void -devctl_safe_quote(char *dst, const char *src, size_t len) +devctl_safe_quote_sb(struct sbuf *sb, const char *src) { - char *walker = dst, *ep = dst + len - 1; - if (len == 0) - return; - while (src != NULL && walker < ep) - { - if (*src == '"' || *src == '\\') { - if (ep - walker < 2) - break; - *walker++ = '\\'; - } - *walker++ = *src++; + while (*src != '\0') { + if (*src == '"' || *src == '\\') + sbuf_putc(sb, '\\'); + sbuf_putc(sb, *src++); } - *walker = '\0'; } /* End of /dev/devctl code */ @@ -1204,7 +1200,11 @@ devclass_add_driver(devclass_t dc, driver_t *driver, int pass, devclass_t *dcp) dl->pass = pass; driver_register_pass(dl); - devclass_driver_added(dc, driver); + if (device_frozen) { + dl->flags |= DL_DEFERRED_PROBE; + } else { + devclass_driver_added(dc, driver); + } bus_data_generation_update(); return (0); } @@ -1244,6 +1244,9 @@ devclass_driver_deleted(devclass_t busclass, devclass_t dc, driver_t *driver) * Note that since a driver can be in multiple devclasses, we * should not detach devices which are not children of devices in * the affected devclass. + * + * If we're frozen, we don't generate NOMATCH events. Mark to + * generate later. */ for (i = 0; i < dc->maxunit; i++) { if (dc->devices[i]) { @@ -1252,9 +1255,14 @@ devclass_driver_deleted(devclass_t busclass, devclass_t dc, driver_t *driver) dev->parent->devclass == busclass) { if ((error = device_detach(dev)) != 0) return (error); - BUS_PROBE_NOMATCH(dev->parent, dev); - devnomatch(dev); - dev->flags |= DF_DONENOMATCH; + if (device_frozen) { + dev->flags &= ~DF_DONENOMATCH; + dev->flags |= DF_NEEDNOMATCH; + } else { + BUS_PROBE_NOMATCH(dev->parent, dev); + devnomatch(dev); + dev->flags |= DF_DONENOMATCH; + } } } } @@ -2958,6 +2966,7 @@ int device_attach(device_t dev) { uint64_t attachtime; + uint16_t attachentropy; int error; #ifndef __rtems__ @@ -2985,19 +2994,12 @@ device_attach(device_t dev) dev->state = DS_NOTPRESENT; return (error); } - attachtime = get_cyclecount() - attachtime; - /* - * 4 bits per device is a reasonable value for desktop and server - * hardware with good get_cyclecount() implementations, but WILL - * need to be adjusted on other platforms. + dev->flags |= DF_ATTACHED_ONCE; + /* We only need the low bits of this time, but ranges from tens to thousands + * have been seen, so keep 2 bytes' worth. */ -#define RANDOM_PROBE_BIT_GUESS 4 - if (bootverbose) - printf("random: harvesting attach, %zu bytes (%d bits) from %s%d\n", - sizeof(attachtime), RANDOM_PROBE_BIT_GUESS, - dev->driver->name, dev->unit); - random_harvest_direct(&attachtime, sizeof(attachtime), - RANDOM_PROBE_BIT_GUESS, RANDOM_ATTACH); + attachentropy = (uint16_t)(get_cyclecount() - attachtime); + random_harvest_direct(&attachentropy, sizeof(attachentropy), RANDOM_ATTACH); device_sysctl_update(dev); if (dev->busy) dev->state = DS_BUSY; @@ -5474,6 +5476,53 @@ driver_exists(device_t bus, const char *driver) return (false); } +static void +device_gen_nomatch(device_t dev) +{ + device_t child; + + if (dev->flags & DF_NEEDNOMATCH && + dev->state == DS_NOTPRESENT) { + BUS_PROBE_NOMATCH(dev->parent, dev); + devnomatch(dev); + dev->flags |= DF_DONENOMATCH; + } + dev->flags &= ~DF_NEEDNOMATCH; + TAILQ_FOREACH(child, &dev->children, link) { + device_gen_nomatch(child); + } +} + +static void +device_do_deferred_actions(void) +{ + devclass_t dc; + driverlink_t dl; + + /* + * Walk through the devclasses to find all the drivers we've tagged as + * deferred during the freeze and call the driver added routines. They + * have already been added to the lists in the background, so the driver + * added routines that trigger a probe will have all the right bidders + * for the probe auction. + */ + TAILQ_FOREACH(dc, &devclasses, link) { + TAILQ_FOREACH(dl, &dc->drivers, link) { + if (dl->flags & DL_DEFERRED_PROBE) { + devclass_driver_added(dc, dl->driver); + dl->flags &= ~DL_DEFERRED_PROBE; + } + } + } + + /* + * We also defer no-match events during a freeze. Walk the tree and + * generate all the pent-up events that are still relevant. + */ + device_gen_nomatch(root_bus); + bus_data_generation_update(); +} + static int devctl2_ioctl(struct cdev *cdev, u_long cmd, caddr_t data, int fflag, struct thread *td) @@ -5500,6 +5549,10 @@ devctl2_ioctl(struct cdev *cdev, u_long cmd, caddr_t data, int fflag, if (error == 0) error = find_device(req, &dev); break; + case DEV_FREEZE: + case DEV_THAW: + error = priv_check(td, PRIV_DRIVER); + break; default: error = ENOTTY; break; @@ -5703,7 +5756,23 @@ devctl2_ioctl(struct cdev *cdev, u_long cmd, caddr_t data, int fflag, error = device_delete_child(parent, dev); break; } +#ifndef __rtems__ + case DEV_FREEZE: + if (device_frozen) + error = EBUSY; + else + device_frozen = true; + break; + case DEV_THAW: + if (!device_frozen) + error = EBUSY; + else { + device_do_deferred_actions(); + device_frozen = false; + } + break; } +#endif /* __rtems__ */ mtx_unlock(&Giant); return (error); } |