From: <gregkh@linuxfoundation.org>
To: stern@rowland.harvard.edu, christopher.a.dickens@gmail.com,
gregkh@linuxfoundation.org, hdegoede@redhat.com
Cc: <stable@vger.kernel.org>, <stable-commits@vger.kernel.org>
Subject: Patch "USB: usbfs: allow URBs to be reaped after disconnection" has been added to the 3.10-stable tree
Date: Fri, 31 Jul 2015 09:59:09 -0700 [thread overview]
Message-ID: <143836194964111@kroah.com> (raw)
This is a note to let you know that I've just added the patch titled
USB: usbfs: allow URBs to be reaped after disconnection
to the 3.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
usb-usbfs-allow-urbs-to-be-reaped-after-disconnection.patch
and it can be found in the queue-3.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.
>From 3f2cee73b650921b2e214bf487b2061a1c266504 Mon Sep 17 00:00:00 2001
From: Alan Stern <stern@rowland.harvard.edu>
Date: Thu, 29 Jan 2015 11:29:13 -0500
Subject: USB: usbfs: allow URBs to be reaped after disconnection
From: Alan Stern <stern@rowland.harvard.edu>
commit 3f2cee73b650921b2e214bf487b2061a1c266504 upstream.
The usbfs API has a peculiar hole: Users are not allowed to reap their
URBs after the device has been disconnected. There doesn't seem to be
any good reason for this; it is an ad-hoc inconsistency.
The patch allows users to issue the USBDEVFS_REAPURB and
USBDEVFS_REAPURBNDELAY ioctls (together with their 32-bit counterparts
on 64-bit systems) even after the device is gone. If no URBs are
pending for a disconnected device then the ioctls will return -ENODEV
rather than -EAGAIN, because obviously no new URBs will ever be able
to complete.
The patch also adds a new capability flag for
USBDEVFS_GET_CAPABILITIES to indicate that the reap-after-disconnect
feature is supported.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Chris Dickens <christopher.a.dickens@gmail.com>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/usb/core/devio.c | 63 ++++++++++++++++++++++----------------
include/uapi/linux/usbdevice_fs.h | 3 +
2 files changed, 39 insertions(+), 27 deletions(-)
--- a/drivers/usb/core/devio.c
+++ b/drivers/usb/core/devio.c
@@ -1593,7 +1593,7 @@ static struct async *reap_as(struct dev_
for (;;) {
__set_current_state(TASK_INTERRUPTIBLE);
as = async_getcompleted(ps);
- if (as)
+ if (as || !connected(ps))
break;
if (signal_pending(current))
break;
@@ -1616,7 +1616,7 @@ static int proc_reapurb(struct dev_state
}
if (signal_pending(current))
return -EINTR;
- return -EIO;
+ return -ENODEV;
}
static int proc_reapurbnonblock(struct dev_state *ps, void __user *arg)
@@ -1625,10 +1625,11 @@ static int proc_reapurbnonblock(struct d
struct async *as;
as = async_getcompleted(ps);
- retval = -EAGAIN;
if (as) {
retval = processcompl(as, (void __user * __user *)arg);
free_async(as);
+ } else {
+ retval = (connected(ps) ? -EAGAIN : -ENODEV);
}
return retval;
}
@@ -1758,7 +1759,7 @@ static int proc_reapurb_compat(struct de
}
if (signal_pending(current))
return -EINTR;
- return -EIO;
+ return -ENODEV;
}
static int proc_reapurbnonblock_compat(struct dev_state *ps, void __user *arg)
@@ -1766,11 +1767,12 @@ static int proc_reapurbnonblock_compat(s
int retval;
struct async *as;
- retval = -EAGAIN;
as = async_getcompleted(ps);
if (as) {
retval = processcompl_compat(as, (void __user * __user *)arg);
free_async(as);
+ } else {
+ retval = (connected(ps) ? -EAGAIN : -ENODEV);
}
return retval;
}
@@ -1941,7 +1943,8 @@ static int proc_get_capabilities(struct
{
__u32 caps;
- caps = USBDEVFS_CAP_ZERO_PACKET | USBDEVFS_CAP_NO_PACKET_SIZE_LIM;
+ caps = USBDEVFS_CAP_ZERO_PACKET | USBDEVFS_CAP_NO_PACKET_SIZE_LIM |
+ USBDEVFS_CAP_REAP_AFTER_DISCONNECT;
if (!ps->dev->bus->no_stop_on_short)
caps |= USBDEVFS_CAP_BULK_CONTINUATION;
if (ps->dev->bus->sg_tablesize)
@@ -2002,6 +2005,32 @@ static long usbdev_do_ioctl(struct file
return -EPERM;
usb_lock_device(dev);
+
+ /* Reap operations are allowed even after disconnection */
+ switch (cmd) {
+ case USBDEVFS_REAPURB:
+ snoop(&dev->dev, "%s: REAPURB\n", __func__);
+ ret = proc_reapurb(ps, p);
+ goto done;
+
+ case USBDEVFS_REAPURBNDELAY:
+ snoop(&dev->dev, "%s: REAPURBNDELAY\n", __func__);
+ ret = proc_reapurbnonblock(ps, p);
+ goto done;
+
+#ifdef CONFIG_COMPAT
+ case USBDEVFS_REAPURB32:
+ snoop(&dev->dev, "%s: REAPURB32\n", __func__);
+ ret = proc_reapurb_compat(ps, p);
+ goto done;
+
+ case USBDEVFS_REAPURBNDELAY32:
+ snoop(&dev->dev, "%s: REAPURBNDELAY32\n", __func__);
+ ret = proc_reapurbnonblock_compat(ps, p);
+ goto done;
+#endif
+ }
+
if (!connected(ps)) {
usb_unlock_device(dev);
return -ENODEV;
@@ -2095,16 +2124,6 @@ static long usbdev_do_ioctl(struct file
inode->i_mtime = CURRENT_TIME;
break;
- case USBDEVFS_REAPURB32:
- snoop(&dev->dev, "%s: REAPURB32\n", __func__);
- ret = proc_reapurb_compat(ps, p);
- break;
-
- case USBDEVFS_REAPURBNDELAY32:
- snoop(&dev->dev, "%s: REAPURBNDELAY32\n", __func__);
- ret = proc_reapurbnonblock_compat(ps, p);
- break;
-
case USBDEVFS_IOCTL32:
snoop(&dev->dev, "%s: IOCTL32\n", __func__);
ret = proc_ioctl_compat(ps, ptr_to_compat(p));
@@ -2116,16 +2135,6 @@ static long usbdev_do_ioctl(struct file
ret = proc_unlinkurb(ps, p);
break;
- case USBDEVFS_REAPURB:
- snoop(&dev->dev, "%s: REAPURB\n", __func__);
- ret = proc_reapurb(ps, p);
- break;
-
- case USBDEVFS_REAPURBNDELAY:
- snoop(&dev->dev, "%s: REAPURBNDELAY\n", __func__);
- ret = proc_reapurbnonblock(ps, p);
- break;
-
case USBDEVFS_DISCSIGNAL:
snoop(&dev->dev, "%s: DISCSIGNAL\n", __func__);
ret = proc_disconnectsignal(ps, p);
@@ -2162,6 +2171,8 @@ static long usbdev_do_ioctl(struct file
ret = proc_disconnect_claim(ps, p);
break;
}
+
+ done:
usb_unlock_device(dev);
if (ret >= 0)
inode->i_atime = CURRENT_TIME;
--- a/include/uapi/linux/usbdevice_fs.h
+++ b/include/uapi/linux/usbdevice_fs.h
@@ -125,11 +125,12 @@ struct usbdevfs_hub_portinfo {
char port [127]; /* e.g. port 3 connects to device 27 */
};
-/* Device capability flags */
+/* System and bus capability flags */
#define USBDEVFS_CAP_ZERO_PACKET 0x01
#define USBDEVFS_CAP_BULK_CONTINUATION 0x02
#define USBDEVFS_CAP_NO_PACKET_SIZE_LIM 0x04
#define USBDEVFS_CAP_BULK_SCATTER_GATHER 0x08
+#define USBDEVFS_CAP_REAP_AFTER_DISCONNECT 0x10
/* USBDEVFS_DISCONNECT_CLAIM flags & struct */
Patches currently in stable-queue which might be from stern@rowland.harvard.edu are
queue-3.10/usb-usbfs-allow-urbs-to-be-reaped-after-disconnection.patch
queue-3.10/usb-devio-fix-a-condition-in-async_completed.patch
reply other threads:[~2015-07-31 16:59 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=143836194964111@kroah.com \
--to=gregkh@linuxfoundation.org \
--cc=christopher.a.dickens@gmail.com \
--cc=hdegoede@redhat.com \
--cc=stable-commits@vger.kernel.org \
--cc=stable@vger.kernel.org \
--cc=stern@rowland.harvard.edu \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.