| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <4a1dcbcfb28ea2d18b09561a370efe7a4b0a2c5f.1365590805.git.jbenc@redhat.com>
Date: Wed, 10 Apr 2013 12:47:31 +0200
From: Jiri Benc <jbenc@...hat.com>
To: netdev@...r.kernel.org
Cc: Richard Cochran <richardcochran@...il.com>
Subject: [PATCH net-next] ptp: dynamic allocation of PHC char devices
As network adapters supporting PTP are becoming more common, machines with
many NICs suddenly have many PHCs, too. The current limit of eight /dev/ptp*
char devices (and thus, 8 network interfaces with PHC) is insufficient. Let
the ptp driver allocate the char devices dynamically.
The character devices are allocated in chunks. idr is used for tracking
minor numbers allocation; the mapping from index to pointer is not used, as
it is not needed for posix clocks.
Tested with 28 PHCs, removing and re-adding some of them.
Signed-off-by: Jiri Benc <jbenc@...hat.com>
---
drivers/ptp/ptp_clock.c | 81 ++++++++++++++++++++++++++++++++++-------------
1 files changed, 59 insertions(+), 22 deletions(-)
diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c
index 79f4bce..9d07641 100644
--- a/drivers/ptp/ptp_clock.c
+++ b/drivers/ptp/ptp_clock.c
@@ -17,7 +17,7 @@
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
-#include <linux/bitops.h>
+#include <linux/idr.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/init.h>
@@ -32,7 +32,7 @@
#include "ptp_private.h"
#define PTP_MAX_ALARMS 4
-#define PTP_MAX_CLOCKS 8
+#define PTP_CLOCKS_CHUNK 8
#define PTP_PPS_DEFAULTS (PPS_CAPTUREASSERT | PPS_OFFSETASSERT)
#define PTP_PPS_EVENT PPS_CAPTUREASSERT
#define PTP_PPS_MODE (PTP_PPS_DEFAULTS | PPS_CANWAIT | PPS_TSFMT_TSPEC)
@@ -40,9 +40,10 @@
/* private globals */
static dev_t ptp_devt;
+static int ptp_devt_count;
static struct class *ptp_class;
-static DECLARE_BITMAP(ptp_clocks_map, PTP_MAX_CLOCKS);
+static struct idr ptp_clocks_map;
static DEFINE_MUTEX(ptp_clocks_mutex); /* protects 'ptp_clocks_map' */
/* time stamp event queue operations */
@@ -166,17 +167,51 @@ static struct posix_clock_operations ptp_clock_ops = {
.read = ptp_read,
};
-static void delete_ptp_clock(struct posix_clock *pc)
+static int ptp_clock_alloc_index(struct ptp_clock *ptp)
{
- struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
+ int index, err, major = MAJOR(ptp_devt);
- mutex_destroy(&ptp->tsevq_mux);
+ mutex_lock(&ptp_clocks_mutex);
+ index = idr_alloc(&ptp_clocks_map, ptp, 0, 0, GFP_KERNEL);
+ if (index < 0)
+ goto no_idr;
+ if (index >= ptp_devt_count) {
+ err = -EBUSY;
+ if (ptp_devt_count + PTP_CLOCKS_CHUNK - 1 > MINORMASK)
+ goto no_devt;
+ err = register_chrdev_region(MKDEV(major, ptp_devt_count),
+ PTP_CLOCKS_CHUNK, "ptp");
+ if (err < 0)
+ goto no_devt;
+ ptp_devt_count += PTP_CLOCKS_CHUNK;
+ }
+ err = -EBUSY;
+ if (WARN_ON(index >= ptp_devt_count))
+ goto no_devt;
+ mutex_unlock(&ptp_clocks_mutex);
+ return index;
- /* Remove the clock from the bit map. */
+no_devt:
+ idr_remove(&ptp_clocks_map, index);
+ index = err;
+no_idr:
+ mutex_unlock(&ptp_clocks_mutex);
+ return index;
+}
+
+static void ptp_clock_free_index(int index)
+{
mutex_lock(&ptp_clocks_mutex);
- clear_bit(ptp->index, ptp_clocks_map);
+ idr_remove(&ptp_clocks_map, index);
mutex_unlock(&ptp_clocks_mutex);
+}
+
+static void delete_ptp_clock(struct posix_clock *pc)
+{
+ struct ptp_clock *ptp = container_of(pc, struct ptp_clock, clock);
+ mutex_destroy(&ptp->tsevq_mux);
+ ptp_clock_free_index(ptp->index);
kfree(ptp);
}
@@ -191,21 +226,18 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
if (info->n_alarm > PTP_MAX_ALARMS)
return ERR_PTR(-EINVAL);
- /* Find a free clock slot and reserve it. */
- err = -EBUSY;
- mutex_lock(&ptp_clocks_mutex);
- index = find_first_zero_bit(ptp_clocks_map, PTP_MAX_CLOCKS);
- if (index < PTP_MAX_CLOCKS)
- set_bit(index, ptp_clocks_map);
- else
- goto no_slot;
-
/* Initialize a clock structure. */
err = -ENOMEM;
ptp = kzalloc(sizeof(struct ptp_clock), GFP_KERNEL);
if (ptp == NULL)
goto no_memory;
+ index = ptp_clock_alloc_index(ptp);
+ if (index < 0) {
+ err = index;
+ goto no_slot;
+ }
+
ptp->clock.ops = ptp_clock_ops;
ptp->clock.release = delete_ptp_clock;
ptp->info = info;
@@ -260,11 +292,10 @@ no_sysfs:
device_destroy(ptp_class, ptp->devid);
no_device:
mutex_destroy(&ptp->tsevq_mux);
+ ptp_clock_free_index(index);
+no_slot:
kfree(ptp);
no_memory:
- clear_bit(index, ptp_clocks_map);
-no_slot:
- mutex_unlock(&ptp_clocks_mutex);
return ERR_PTR(err);
}
EXPORT_SYMBOL(ptp_clock_register);
@@ -322,8 +353,12 @@ EXPORT_SYMBOL(ptp_clock_index);
static void __exit ptp_exit(void)
{
+ int i, major = MAJOR(ptp_devt);
+
class_destroy(ptp_class);
- unregister_chrdev_region(ptp_devt, PTP_MAX_CLOCKS);
+ for (i = 0; i < ptp_devt_count; i += PTP_CLOCKS_CHUNK)
+ unregister_chrdev_region(MKDEV(major, i), PTP_CLOCKS_CHUNK);
+ idr_destroy(&ptp_clocks_map);
}
static int __init ptp_init(void)
@@ -336,11 +371,13 @@ static int __init ptp_init(void)
return PTR_ERR(ptp_class);
}
- err = alloc_chrdev_region(&ptp_devt, 0, PTP_MAX_CLOCKS, "ptp");
+ idr_init(&ptp_clocks_map);
+ err = alloc_chrdev_region(&ptp_devt, 0, PTP_CLOCKS_CHUNK, "ptp");
if (err < 0) {
pr_err("ptp: failed to allocate device region\n");
goto no_region;
}
+ ptp_devt_count = PTP_CLOCKS_CHUNK;
ptp_class->dev_attrs = ptp_dev_attrs;
pr_info("PTP clock support registered\n");
--
1.7.6.5
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists