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Differential D27413 Diff 82975 sys/kern/subr_firmware.c

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sys/kern/subr_firmware.c

Show First 20 Lines • Show All 232 Lines • ▼ Show 20 Lines if (fp == NULL) {
free(__DECONST(char *, fp->fw.name), M_FIRMWARE); free(__DECONST(char *, fp->fw.name), M_FIRMWARE);
free(fp, M_FIRMWARE); free(fp, M_FIRMWARE);
err = 0; err = 0;
} }
mtx_unlock(&firmware_mtx); mtx_unlock(&firmware_mtx);
return (err); return (err);
} }
struct fw_loadimage {
const char *imagename;
uint32_t flags;
};
static void static void
loadimage(void *arg, int npending) loadimage(void *arg, int npending __unused)
{ {
char *imagename = arg; struct fw_loadimage *fwli = arg;
struct priv_fw *fp; struct priv_fw *fp;
linker_file_t result; linker_file_t result;
int error; int error;
error = linker_reference_module(imagename, NULL, &result); error = linker_reference_module(fwli->imagename, NULL, &result);
if (error != 0) { if (error != 0) {
if (bootverbose || (fwli->flags & FIRMWARE_GET_NOWARN) == 0)
printf("%s: could not load firmware image, error %d\n", printf("%s: could not load firmware image, error %d\n",
imagename, error); fwli->imagename, error);
mtx_lock(&firmware_mtx); mtx_lock(&firmware_mtx);
goto done; goto done;
} }
mtx_lock(&firmware_mtx); mtx_lock(&firmware_mtx);
fp = lookup(imagename); fp = lookup(fwli->imagename);
if (fp == NULL || fp->file != NULL) { if (fp == NULL || fp->file != NULL) {
mtx_unlock(&firmware_mtx); mtx_unlock(&firmware_mtx);
if (fp == NULL) if (fp == NULL)
printf("%s: firmware image loaded, " printf("%s: firmware image loaded, "
"but did not register\n", imagename); "but did not register\n", fwli->imagename);
(void) linker_release_module(imagename, NULL, NULL); (void) linker_release_module(fwli->imagename, NULL, NULL);
mtx_lock(&firmware_mtx); mtx_lock(&firmware_mtx);
goto done; goto done;
} }
fp->file = result; /* record the module identity */ fp->file = result; /* record the module identity */
done: done:
wakeup_one(imagename); wakeup_one(arg);
mtx_unlock(&firmware_mtx); mtx_unlock(&firmware_mtx);
} }
/* /*
* Lookup and potentially load the specified firmware image. * Lookup and potentially load the specified firmware image.
* If the firmware is not found in the registry, try to load a kernel * If the firmware is not found in the registry, try to load a kernel
* module named as the image name. * module named as the image name.
* If the firmware is located, a reference is returned. The caller must * If the firmware is located, a reference is returned. The caller must
* release this reference for the image to be eligible for removal/unload. * release this reference for the image to be eligible for removal/unload.
*/ */
const struct firmware * const struct firmware *
firmware_get(const char *imagename) firmware_get_flags(const char *imagename, uint32_t flags)
{ {
struct task fwload_task; struct task fwload_task;
struct thread *td; struct thread *td;
struct priv_fw *fp; struct priv_fw *fp;
mtx_lock(&firmware_mtx); mtx_lock(&firmware_mtx);
fp = lookup(imagename); fp = lookup(imagename);
if (fp != NULL) if (fp != NULL)
Show All 10 Lines if (priv_check(td, PRIV_FIRMWARE_LOAD) != 0 ||
return NULL; return NULL;
} }
/* /*
* Defer load to a thread with known context. linker_reference_module * Defer load to a thread with known context. linker_reference_module
* may do filesystem i/o which requires root & current dirs, etc. * may do filesystem i/o which requires root & current dirs, etc.
* Also we must not hold any mtx's over this call which is problematic. * Also we must not hold any mtx's over this call which is problematic.
*/ */
if (!cold) { if (!cold) {
TASK_INIT(&fwload_task, 0, loadimage, __DECONST(void *, struct fw_loadimage fwli;
imagename));
fwli.imagename = imagename;
fwli.flags = flags;
TASK_INIT(&fwload_task, 0, loadimage, (void *)&fwli);
taskqueue_enqueue(firmware_tq, &fwload_task); taskqueue_enqueue(firmware_tq, &fwload_task);
msleep(__DECONST(void *, imagename), &firmware_mtx, 0, PHOLD(curproc);
"fwload", 0); msleep((void *)&fwli, &firmware_mtx, 0, "fwload", 0);
PRELE(curproc);
markjUnsubmitted
Done
Inline Actions

Do you have to PHOLD across this sleep? If the kernel stack is swapped out, the thread accessing fwli can trigger a page fault otherwise. The likelihood of this happening is very low.

markj: Do you have to PHOLD across this sleep? If the kernel stack is swapped out, the thread…
bzAuthorUnsubmitted
Done
Inline Actions

Good catch. I've been generous with the amount under the "hold" beyond the msleep.

bz: Good catch. I've been generous with the amount under the "hold" beyond the msleep.
markjUnsubmitted
Not Done
Inline Actions

Really you only need it across the msleep() call.

markj: Really you only need it across the msleep() call.
} }
/* /*
* After attempting to load the module, see if the image is registered. * After attempting to load the module, see if the image is registered.
*/ */
fp = lookup(imagename); fp = lookup(imagename);
if (fp == NULL) { if (fp == NULL) {
mtx_unlock(&firmware_mtx); mtx_unlock(&firmware_mtx);
return NULL; return NULL;
} }
found: /* common exit point on success */ found: /* common exit point on success */
if (fp->refcnt == 0 && fp->parent != NULL) if (fp->refcnt == 0 && fp->parent != NULL)
fp->parent->refcnt++; fp->parent->refcnt++;
fp->refcnt++; fp->refcnt++;
mtx_unlock(&firmware_mtx); mtx_unlock(&firmware_mtx);
return &fp->fw; return &fp->fw;
}
const struct firmware *
firmware_get(const char *imagename)
{
return (firmware_get_flags(imagename, 0));
} }
/* /*
* Release a reference to a firmware image returned by firmware_get. * Release a reference to a firmware image returned by firmware_get.
* The caller may specify, with the FIRMWARE_UNLOAD flag, its desire * The caller may specify, with the FIRMWARE_UNLOAD flag, its desire
* to release the resource, but the flag is only advisory. * to release the resource, but the flag is only advisory.
* *
* If this is the last reference to the firmware image, and this is an * If this is the last reference to the firmware image, and this is an
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