From 882f312dc0751c973db26478f07f082c584d16aa Mon Sep 17 00:00:00 2001 From: Dmitry Torokhov Date: Tue, 14 Feb 2017 10:23:31 -0800 Subject: [PATCH 1/4] ptp: do not explicitly set drvdata in ptp_clock_register() We do not need explicitly call dev_set_drvdata(), as it is done for us by device_create(). Acked-by: Richard Cochran Signed-off-by: Dmitry Torokhov Signed-off-by: David S. Miller --- drivers/ptp/ptp_clock.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c index 9c13381b6966..b4e5e8022c29 100644 --- a/drivers/ptp/ptp_clock.c +++ b/drivers/ptp/ptp_clock.c @@ -227,8 +227,6 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info, if (IS_ERR(ptp->dev)) goto no_device; - dev_set_drvdata(ptp->dev, ptp); - err = ptp_populate_sysfs(ptp); if (err) goto no_sysfs; From 6f7aa56bae6ff38727d5c8bf6ee7d4202b4e3865 Mon Sep 17 00:00:00 2001 From: Dmitry Torokhov Date: Tue, 14 Feb 2017 10:23:32 -0800 Subject: [PATCH 2/4] ptp: use kcalloc when allocating arrays kcalloc is more semantically correct when allocating arrays of objects, and overflow-safe. Signed-off-by: Dmitry Torokhov Signed-off-by: David S. Miller --- drivers/ptp/ptp_sysfs.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/ptp/ptp_sysfs.c b/drivers/ptp/ptp_sysfs.c index 53d43954a974..27cd46ab5e32 100644 --- a/drivers/ptp/ptp_sysfs.c +++ b/drivers/ptp/ptp_sysfs.c @@ -269,13 +269,12 @@ static int ptp_populate_pins(struct ptp_clock *ptp) struct ptp_clock_info *info = ptp->info; int err = -ENOMEM, i, n_pins = info->n_pins; - ptp->pin_dev_attr = kzalloc(n_pins * sizeof(*ptp->pin_dev_attr), + ptp->pin_dev_attr = kcalloc(n_pins, sizeof(*ptp->pin_dev_attr), GFP_KERNEL); if (!ptp->pin_dev_attr) goto no_dev_attr; - ptp->pin_attr = kzalloc((1 + n_pins) * sizeof(struct attribute *), - GFP_KERNEL); + ptp->pin_attr = kcalloc(1 + n_pins, sizeof(*ptp->pin_attr), GFP_KERNEL); if (!ptp->pin_attr) goto no_pin_attr; From af59e717d5ff9c8dbf9bcc581c0dfb3b2a9c9030 Mon Sep 17 00:00:00 2001 From: Dmitry Torokhov Date: Tue, 14 Feb 2017 10:23:33 -0800 Subject: [PATCH 3/4] ptp: use is_visible method to hide unused attributes Instead of creating selected attributes after the device is created (and after userspace potentially seen uevent), lets use attribute group is_visible() method to control which attributes are shown. This will allow us to create all attributes (except "pins" group, which will be taken care of later) before userspace gets notified about new ptp class device. Signed-off-by: Dmitry Torokhov Signed-off-by: David S. Miller --- drivers/ptp/ptp_sysfs.c | 125 ++++++++++++++++++---------------------- 1 file changed, 55 insertions(+), 70 deletions(-) diff --git a/drivers/ptp/ptp_sysfs.c b/drivers/ptp/ptp_sysfs.c index 27cd46ab5e32..426e42c51df4 100644 --- a/drivers/ptp/ptp_sysfs.c +++ b/drivers/ptp/ptp_sysfs.c @@ -46,27 +46,6 @@ PTP_SHOW_INT(n_periodic_outputs, n_per_out); PTP_SHOW_INT(n_programmable_pins, n_pins); PTP_SHOW_INT(pps_available, pps); -static struct attribute *ptp_attrs[] = { - &dev_attr_clock_name.attr, - &dev_attr_max_adjustment.attr, - &dev_attr_n_alarms.attr, - &dev_attr_n_external_timestamps.attr, - &dev_attr_n_periodic_outputs.attr, - &dev_attr_n_programmable_pins.attr, - &dev_attr_pps_available.attr, - NULL, -}; - -static const struct attribute_group ptp_group = { - .attrs = ptp_attrs, -}; - -const struct attribute_group *ptp_groups[] = { - &ptp_group, - NULL, -}; - - static ssize_t extts_enable_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) @@ -91,6 +70,7 @@ static ssize_t extts_enable_store(struct device *dev, out: return err; } +static DEVICE_ATTR(extts_enable, 0220, NULL, extts_enable_store); static ssize_t extts_fifo_show(struct device *dev, struct device_attribute *attr, char *page) @@ -124,6 +104,7 @@ out: mutex_unlock(&ptp->tsevq_mux); return cnt; } +static DEVICE_ATTR(fifo, 0444, extts_fifo_show, NULL); static ssize_t period_store(struct device *dev, struct device_attribute *attr, @@ -151,6 +132,7 @@ static ssize_t period_store(struct device *dev, out: return err; } +static DEVICE_ATTR(period, 0220, NULL, period_store); static ssize_t pps_enable_store(struct device *dev, struct device_attribute *attr, @@ -177,6 +159,57 @@ static ssize_t pps_enable_store(struct device *dev, out: return err; } +static DEVICE_ATTR(pps_enable, 0220, NULL, pps_enable_store); + +static struct attribute *ptp_attrs[] = { + &dev_attr_clock_name.attr, + + &dev_attr_max_adjustment.attr, + &dev_attr_n_alarms.attr, + &dev_attr_n_external_timestamps.attr, + &dev_attr_n_periodic_outputs.attr, + &dev_attr_n_programmable_pins.attr, + &dev_attr_pps_available.attr, + + &dev_attr_extts_enable.attr, + &dev_attr_fifo.attr, + &dev_attr_period.attr, + &dev_attr_pps_enable.attr, + NULL +}; + +static umode_t ptp_is_attribute_visible(struct kobject *kobj, + struct attribute *attr, int n) +{ + struct device *dev = kobj_to_dev(kobj); + struct ptp_clock *ptp = dev_get_drvdata(dev); + struct ptp_clock_info *info = ptp->info; + umode_t mode = attr->mode; + + if (attr == &dev_attr_extts_enable.attr || + attr == &dev_attr_fifo.attr) { + if (!info->n_ext_ts) + mode = 0; + } else if (attr == &dev_attr_period.attr) { + if (!info->n_per_out) + mode = 0; + } else if (attr == &dev_attr_pps_enable.attr) { + if (!info->pps) + mode = 0; + } + + return mode; +} + +static const struct attribute_group ptp_group = { + .is_visible = ptp_is_attribute_visible, + .attrs = ptp_attrs, +}; + +const struct attribute_group *ptp_groups[] = { + &ptp_group, + NULL +}; static int ptp_pin_name2index(struct ptp_clock *ptp, const char *name) { @@ -235,26 +268,11 @@ static ssize_t ptp_pin_store(struct device *dev, struct device_attribute *attr, return count; } -static DEVICE_ATTR(extts_enable, 0220, NULL, extts_enable_store); -static DEVICE_ATTR(fifo, 0444, extts_fifo_show, NULL); -static DEVICE_ATTR(period, 0220, NULL, period_store); -static DEVICE_ATTR(pps_enable, 0220, NULL, pps_enable_store); - int ptp_cleanup_sysfs(struct ptp_clock *ptp) { struct device *dev = ptp->dev; struct ptp_clock_info *info = ptp->info; - if (info->n_ext_ts) { - device_remove_file(dev, &dev_attr_extts_enable); - device_remove_file(dev, &dev_attr_fifo); - } - if (info->n_per_out) - device_remove_file(dev, &dev_attr_period); - - if (info->pps) - device_remove_file(dev, &dev_attr_pps_enable); - if (info->n_pins) { sysfs_remove_group(&dev->kobj, &ptp->pin_attr_group); kfree(ptp->pin_attr); @@ -306,46 +324,13 @@ no_dev_attr: int ptp_populate_sysfs(struct ptp_clock *ptp) { - struct device *dev = ptp->dev; struct ptp_clock_info *info = ptp->info; int err; - if (info->n_ext_ts) { - err = device_create_file(dev, &dev_attr_extts_enable); - if (err) - goto out1; - err = device_create_file(dev, &dev_attr_fifo); - if (err) - goto out2; - } - if (info->n_per_out) { - err = device_create_file(dev, &dev_attr_period); - if (err) - goto out3; - } - if (info->pps) { - err = device_create_file(dev, &dev_attr_pps_enable); - if (err) - goto out4; - } if (info->n_pins) { err = ptp_populate_pins(ptp); if (err) - goto out5; + return err; } return 0; -out5: - if (info->pps) - device_remove_file(dev, &dev_attr_pps_enable); -out4: - if (info->n_per_out) - device_remove_file(dev, &dev_attr_period); -out3: - if (info->n_ext_ts) - device_remove_file(dev, &dev_attr_fifo); -out2: - if (info->n_ext_ts) - device_remove_file(dev, &dev_attr_extts_enable); -out1: - return err; } From 85a66e55019583da1e0f18706b7a8281c9f6de5b Mon Sep 17 00:00:00 2001 From: Dmitry Torokhov Date: Tue, 14 Feb 2017 10:23:34 -0800 Subject: [PATCH 4/4] ptp: create "pins" together with the rest of attributes Let's switch to using device_create_with_groups(), which will allow us to create "pins" attribute group together with the rest of ptp device attributes, and before userspace gets notified about ptp device creation. Signed-off-by: Dmitry Torokhov Signed-off-by: David S. Miller --- drivers/ptp/ptp_clock.c | 20 +++++++++++--------- drivers/ptp/ptp_private.h | 7 ++++--- drivers/ptp/ptp_sysfs.c | 39 +++++++++------------------------------ 3 files changed, 24 insertions(+), 42 deletions(-) diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c index b4e5e8022c29..e8142803a1a7 100644 --- a/drivers/ptp/ptp_clock.c +++ b/drivers/ptp/ptp_clock.c @@ -221,16 +221,17 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info, mutex_init(&ptp->pincfg_mux); init_waitqueue_head(&ptp->tsev_wq); + err = ptp_populate_pin_groups(ptp); + if (err) + goto no_pin_groups; + /* Create a new device in our class. */ - ptp->dev = device_create(ptp_class, parent, ptp->devid, ptp, - "ptp%d", ptp->index); + ptp->dev = device_create_with_groups(ptp_class, parent, ptp->devid, + ptp, ptp->pin_attr_groups, + "ptp%d", ptp->index); if (IS_ERR(ptp->dev)) goto no_device; - err = ptp_populate_sysfs(ptp); - if (err) - goto no_sysfs; - /* Register a new PPS source. */ if (info->pps) { struct pps_source_info pps; @@ -258,10 +259,10 @@ no_clock: if (ptp->pps_source) pps_unregister_source(ptp->pps_source); no_pps: - ptp_cleanup_sysfs(ptp); -no_sysfs: device_destroy(ptp_class, ptp->devid); no_device: + ptp_cleanup_pin_groups(ptp); +no_pin_groups: mutex_destroy(&ptp->tsevq_mux); mutex_destroy(&ptp->pincfg_mux); ida_simple_remove(&ptp_clocks_map, index); @@ -280,8 +281,9 @@ int ptp_clock_unregister(struct ptp_clock *ptp) /* Release the clock's resources. */ if (ptp->pps_source) pps_unregister_source(ptp->pps_source); - ptp_cleanup_sysfs(ptp); + device_destroy(ptp_class, ptp->devid); + ptp_cleanup_pin_groups(ptp); posix_clock_unregister(&ptp->clock); return 0; diff --git a/drivers/ptp/ptp_private.h b/drivers/ptp/ptp_private.h index 9c5d41421b65..d95888974d0c 100644 --- a/drivers/ptp/ptp_private.h +++ b/drivers/ptp/ptp_private.h @@ -54,6 +54,8 @@ struct ptp_clock { struct device_attribute *pin_dev_attr; struct attribute **pin_attr; struct attribute_group pin_attr_group; + /* 1st entry is a pointer to the real group, 2nd is NULL terminator */ + const struct attribute_group *pin_attr_groups[2]; }; /* @@ -94,8 +96,7 @@ uint ptp_poll(struct posix_clock *pc, extern const struct attribute_group *ptp_groups[]; -int ptp_cleanup_sysfs(struct ptp_clock *ptp); - -int ptp_populate_sysfs(struct ptp_clock *ptp); +int ptp_populate_pin_groups(struct ptp_clock *ptp); +void ptp_cleanup_pin_groups(struct ptp_clock *ptp); #endif diff --git a/drivers/ptp/ptp_sysfs.c b/drivers/ptp/ptp_sysfs.c index 426e42c51df4..48401dfcd999 100644 --- a/drivers/ptp/ptp_sysfs.c +++ b/drivers/ptp/ptp_sysfs.c @@ -268,25 +268,14 @@ static ssize_t ptp_pin_store(struct device *dev, struct device_attribute *attr, return count; } -int ptp_cleanup_sysfs(struct ptp_clock *ptp) +int ptp_populate_pin_groups(struct ptp_clock *ptp) { - struct device *dev = ptp->dev; - struct ptp_clock_info *info = ptp->info; - - if (info->n_pins) { - sysfs_remove_group(&dev->kobj, &ptp->pin_attr_group); - kfree(ptp->pin_attr); - kfree(ptp->pin_dev_attr); - } - return 0; -} - -static int ptp_populate_pins(struct ptp_clock *ptp) -{ - struct device *dev = ptp->dev; struct ptp_clock_info *info = ptp->info; int err = -ENOMEM, i, n_pins = info->n_pins; + if (!n_pins) + return 0; + ptp->pin_dev_attr = kcalloc(n_pins, sizeof(*ptp->pin_dev_attr), GFP_KERNEL); if (!ptp->pin_dev_attr) @@ -309,28 +298,18 @@ static int ptp_populate_pins(struct ptp_clock *ptp) ptp->pin_attr_group.name = "pins"; ptp->pin_attr_group.attrs = ptp->pin_attr; - err = sysfs_create_group(&dev->kobj, &ptp->pin_attr_group); - if (err) - goto no_group; + ptp->pin_attr_groups[0] = &ptp->pin_attr_group; + return 0; -no_group: - kfree(ptp->pin_attr); no_pin_attr: kfree(ptp->pin_dev_attr); no_dev_attr: return err; } -int ptp_populate_sysfs(struct ptp_clock *ptp) +void ptp_cleanup_pin_groups(struct ptp_clock *ptp) { - struct ptp_clock_info *info = ptp->info; - int err; - - if (info->n_pins) { - err = ptp_populate_pins(ptp); - if (err) - return err; - } - return 0; + kfree(ptp->pin_attr); + kfree(ptp->pin_dev_attr); }