summaryrefslogtreecommitdiffstats
path: root/drivers/base/bus.c
diff options
context:
space:
mode:
authorJason Gunthorpe <jgg@nvidia.com>2021-06-17 16:22:09 +0200
committerAlex Williamson <alex.williamson@redhat.com>2021-06-21 23:29:24 +0200
commit204db60c83574559a8e08ce4bbd0029d56b8ab2e (patch)
tree3741c49db2424f57bb217eee62405067b361a9b7 /drivers/base/bus.c
parentLinux 5.13-rc6 (diff)
downloadlinux-204db60c83574559a8e08ce4bbd0029d56b8ab2e.tar.xz
linux-204db60c83574559a8e08ce4bbd0029d56b8ab2e.zip
driver core: Pull required checks into driver_probe_device()
Checking if the dev is dead or if the dev is already bound is a required precondition to invoking driver_probe_device(). All the call chains leading here duplicate these checks. Add it directly to driver_probe_device() so the precondition is clear and remove the checks from device_driver_attach() and __driver_attach_async_helper(). The other call chain going through __device_attach_driver() does have these same checks but they are inlined into logic higher up the call stack and can't be removed. The sysfs uAPI call chain starting at bind_store() is a bit confused because it reads dev->driver unlocked and returns -ENODEV if it is !NULL, otherwise it reads it again under lock and returns 0 if it is !NULL. Fix this to always return -EBUSY and always read dev->driver under its lock. Done in preparation for the next patches which will add additional callers to driver_probe_device() and will need these checks as well. Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> [hch: drop the extra checks in device_driver_attach and bind_store] Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Link: https://lore.kernel.org/r/20210617142218.1877096-2-hch@lst.de Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Diffstat (limited to 'drivers/base/bus.c')
-rw-r--r--drivers/base/bus.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/base/bus.c b/drivers/base/bus.c
index 36d0c654ea61..7de13302e8c8 100644
--- a/drivers/base/bus.c
+++ b/drivers/base/bus.c
@@ -210,7 +210,7 @@ static ssize_t bind_store(struct device_driver *drv, const char *buf,
int err = -ENODEV;
dev = bus_find_device_by_name(bus, NULL, buf);
- if (dev && dev->driver == NULL && driver_match_device(drv, dev)) {
+ if (dev && driver_match_device(drv, dev)) {
err = device_driver_attach(drv, dev);
if (err > 0) {