Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

[cascardo/linux.git] / drivers / infiniband / hw / hfi1 / debugfs.c

diff --git a/drivers/infiniband/hw/hfi1/debugfs.c b/drivers/infiniband/hw/hfi1/debugfs.c
index a49cc88..5e9be16 100644 (file)
--- a/drivers/infiniband/hw/hfi1/debugfs.c
+++ b/drivers/infiniband/hw/hfi1/debugfs.c
@@ -59,6 +59,40 @@
 
 static struct dentry *hfi1_dbg_root;
 
+/* wrappers to enforce srcu in seq file */
+static ssize_t hfi1_seq_read(
+       struct file *file,
+       char __user *buf,
+       size_t size,
+       loff_t *ppos)
+{
+       struct dentry *d = file->f_path.dentry;
+       int srcu_idx;
+       ssize_t r;
+
+       r = debugfs_use_file_start(d, &srcu_idx);
+       if (likely(!r))
+               r = seq_read(file, buf, size, ppos);
+       debugfs_use_file_finish(srcu_idx);
+       return r;
+}
+
+static loff_t hfi1_seq_lseek(
+       struct file *file,
+       loff_t offset,
+       int whence)
+{
+       struct dentry *d = file->f_path.dentry;
+       int srcu_idx;
+       loff_t r;
+
+       r = debugfs_use_file_start(d, &srcu_idx);
+       if (likely(!r))
+               r = seq_lseek(file, offset, whence);
+       debugfs_use_file_finish(srcu_idx);
+       return r;
+}
+
 #define private2dd(file) (file_inode(file)->i_private)
 #define private2ppd(file) (file_inode(file)->i_private)
 
@@ -87,8 +121,8 @@ static int _##name##_open(struct inode *inode, struct file *s) \
 static const struct file_operations _##name##_file_ops = { \
        .owner   = THIS_MODULE, \
        .open    = _##name##_open, \
-       .read    = seq_read, \
-       .llseek  = seq_lseek, \
+       .read    = hfi1_seq_read, \
+       .llseek  = hfi1_seq_lseek, \
        .release = seq_release \
 }
 
@@ -105,11 +139,9 @@ do { \
        DEBUGFS_FILE_CREATE(#name, parent, data, &_##name##_file_ops, S_IRUGO)
 
 static void *_opcode_stats_seq_start(struct seq_file *s, loff_t *pos)
-__acquires(RCU)
 {
        struct hfi1_opcode_stats_perctx *opstats;
 
-       rcu_read_lock();
        if (*pos >= ARRAY_SIZE(opstats->stats))
                return NULL;
        return pos;
@@ -126,9 +158,7 @@ static void *_opcode_stats_seq_next(struct seq_file *s, void *v, loff_t *pos)
 }
 
 static void _opcode_stats_seq_stop(struct seq_file *s, void *v)
-__releases(RCU)
 {
-       rcu_read_unlock();
 }
 
 static int _opcode_stats_seq_show(struct seq_file *s, void *v)
@@ -285,12 +315,10 @@ DEBUGFS_SEQ_FILE_OPEN(qp_stats)
 DEBUGFS_FILE_OPS(qp_stats);
 
 static void *_sdes_seq_start(struct seq_file *s, loff_t *pos)
-__acquires(RCU)
 {
        struct hfi1_ibdev *ibd;
        struct hfi1_devdata *dd;
 
-       rcu_read_lock();
        ibd = (struct hfi1_ibdev *)s->private;
        dd = dd_from_dev(ibd);
        if (!dd->per_sdma || *pos >= dd->num_sdma)
@@ -310,9 +338,7 @@ static void *_sdes_seq_next(struct seq_file *s, void *v, loff_t *pos)
 }
 
 static void _sdes_seq_stop(struct seq_file *s, void *v)
-__releases(RCU)
 {
-       rcu_read_unlock();
 }
 
 static int _sdes_seq_show(struct seq_file *s, void *v)
@@ -339,11 +365,9 @@ static ssize_t dev_counters_read(struct file *file, char __user *buf,
        struct hfi1_devdata *dd;
        ssize_t rval;
 
-       rcu_read_lock();
        dd = private2dd(file);
        avail = hfi1_read_cntrs(dd, NULL, &counters);
        rval =  simple_read_from_buffer(buf, count, ppos, counters, avail);
-       rcu_read_unlock();
        return rval;
 }
 
@@ -356,11 +380,9 @@ static ssize_t dev_names_read(struct file *file, char __user *buf,
        struct hfi1_devdata *dd;
        ssize_t rval;
 
-       rcu_read_lock();
        dd = private2dd(file);
        avail = hfi1_read_cntrs(dd, &names, NULL);
        rval =  simple_read_from_buffer(buf, count, ppos, names, avail);
-       rcu_read_unlock();
        return rval;
 }
 
@@ -383,11 +405,9 @@ static ssize_t portnames_read(struct file *file, char __user *buf,
        struct hfi1_devdata *dd;
        ssize_t rval;
 
-       rcu_read_lock();
        dd = private2dd(file);
        avail = hfi1_read_portcntrs(dd->pport, &names, NULL);
        rval = simple_read_from_buffer(buf, count, ppos, names, avail);
-       rcu_read_unlock();
        return rval;
 }
 
@@ -400,11 +420,9 @@ static ssize_t portcntrs_debugfs_read(struct file *file, char __user *buf,
        struct hfi1_pportdata *ppd;
        ssize_t rval;
 
-       rcu_read_lock();
        ppd = private2ppd(file);
        avail = hfi1_read_portcntrs(ppd, NULL, &counters);
        rval = simple_read_from_buffer(buf, count, ppos, counters, avail);
-       rcu_read_unlock();
        return rval;
 }
 
@@ -434,16 +452,13 @@ static ssize_t asic_flags_read(struct file *file, char __user *buf,
        int used;
        int i;
 
-       rcu_read_lock();
        ppd = private2ppd(file);
        dd = ppd->dd;
        size = PAGE_SIZE;
        used = 0;
        tmp = kmalloc(size, GFP_KERNEL);
-       if (!tmp) {
-               rcu_read_unlock();
+       if (!tmp)
                return -ENOMEM;
-       }
 
        scratch0 = read_csr(dd, ASIC_CFG_SCRATCH);
        used += scnprintf(tmp + used, size - used,
@@ -470,7 +485,6 @@ static ssize_t asic_flags_read(struct file *file, char __user *buf,
        used += scnprintf(tmp + used, size - used, "Write bits to clear\n");
 
        ret = simple_read_from_buffer(buf, count, ppos, tmp, used);
-       rcu_read_unlock();
        kfree(tmp);
        return ret;
 }
@@ -486,15 +500,12 @@ static ssize_t asic_flags_write(struct file *file, const char __user *buf,
        u64 scratch0;
        u64 clear;
 
-       rcu_read_lock();
        ppd = private2ppd(file);
        dd = ppd->dd;
 
        buff = kmalloc(count + 1, GFP_KERNEL);
-       if (!buff) {
-               ret = -ENOMEM;
-               goto do_return;
-       }
+       if (!buff)
+               return -ENOMEM;
 
        ret = copy_from_user(buff, buf, count);
        if (ret > 0) {
@@ -527,8 +538,6 @@ static ssize_t asic_flags_write(struct file *file, const char __user *buf,
 
  do_free:
        kfree(buff);
- do_return:
-       rcu_read_unlock();
        return ret;
 }
 
@@ -542,18 +551,14 @@ static ssize_t qsfp_debugfs_dump(struct file *file, char __user *buf,
        char *tmp;
        int ret;
 
-       rcu_read_lock();
        ppd = private2ppd(file);
        tmp = kmalloc(PAGE_SIZE, GFP_KERNEL);
-       if (!tmp) {
-               rcu_read_unlock();
+       if (!tmp)
                return -ENOMEM;
-       }
 
        ret = qsfp_dump(ppd, tmp, PAGE_SIZE);
        if (ret > 0)
                ret = simple_read_from_buffer(buf, count, ppos, tmp, ret);
-       rcu_read_unlock();
        kfree(tmp);
        return ret;
 }
@@ -569,7 +574,6 @@ static ssize_t __i2c_debugfs_write(struct file *file, const char __user *buf,
        int offset;
        int total_written;
 
-       rcu_read_lock();
        ppd = private2ppd(file);
 
        /* byte offset format: [offsetSize][i2cAddr][offsetHigh][offsetLow] */
@@ -577,16 +581,12 @@ static ssize_t __i2c_debugfs_write(struct file *file, const char __user *buf,
        offset = *ppos & 0xffff;
 
        /* explicitly reject invalid address 0 to catch cp and cat */
-       if (i2c_addr == 0) {
-               ret = -EINVAL;
-               goto _return;
-       }
+       if (i2c_addr == 0)
+               return -EINVAL;
 
        buff = kmalloc(count, GFP_KERNEL);
-       if (!buff) {
-               ret = -ENOMEM;
-               goto _return;
-       }
+       if (!buff)
+               return -ENOMEM;
 
        ret = copy_from_user(buff, buf, count);
        if (ret > 0) {
@@ -606,8 +606,6 @@ static ssize_t __i2c_debugfs_write(struct file *file, const char __user *buf,
 
  _free:
        kfree(buff);
- _return:
-       rcu_read_unlock();
        return ret;
 }
 
@@ -636,7 +634,6 @@ static ssize_t __i2c_debugfs_read(struct file *file, char __user *buf,
        int offset;
        int total_read;
 
-       rcu_read_lock();
        ppd = private2ppd(file);
 
        /* byte offset format: [offsetSize][i2cAddr][offsetHigh][offsetLow] */
@@ -644,16 +641,12 @@ static ssize_t __i2c_debugfs_read(struct file *file, char __user *buf,
        offset = *ppos & 0xffff;
 
        /* explicitly reject invalid address 0 to catch cp and cat */
-       if (i2c_addr == 0) {
-               ret = -EINVAL;
-               goto _return;
-       }
+       if (i2c_addr == 0)
+               return -EINVAL;
 
        buff = kmalloc(count, GFP_KERNEL);
-       if (!buff) {
-               ret = -ENOMEM;
-               goto _return;
-       }
+       if (!buff)
+               return -ENOMEM;
 
        total_read = i2c_read(ppd, target, i2c_addr, offset, buff, count);
        if (total_read < 0) {
@@ -673,8 +666,6 @@ static ssize_t __i2c_debugfs_read(struct file *file, char __user *buf,
 
  _free:
        kfree(buff);
- _return:
-       rcu_read_unlock();
        return ret;
 }
 
@@ -701,26 +692,20 @@ static ssize_t __qsfp_debugfs_write(struct file *file, const char __user *buf,
        int ret;
        int total_written;
 
-       rcu_read_lock();
-       if (*ppos + count > QSFP_PAGESIZE * 4) { /* base page + page00-page03 */
-               ret = -EINVAL;
-               goto _return;
-       }
+       if (*ppos + count > QSFP_PAGESIZE * 4) /* base page + page00-page03 */
+               return -EINVAL;
 
        ppd = private2ppd(file);
 
        buff = kmalloc(count, GFP_KERNEL);
-       if (!buff) {
-               ret = -ENOMEM;
-               goto _return;
-       }
+       if (!buff)
+               return -ENOMEM;
 
        ret = copy_from_user(buff, buf, count);
        if (ret > 0) {
                ret = -EFAULT;
                goto _free;
        }
-
        total_written = qsfp_write(ppd, target, *ppos, buff, count);
        if (total_written < 0) {
                ret = total_written;
@@ -733,8 +718,6 @@ static ssize_t __qsfp_debugfs_write(struct file *file, const char __user *buf,
 
  _free:
        kfree(buff);
- _return:
-       rcu_read_unlock();
        return ret;
 }
 
@@ -761,7 +744,6 @@ static ssize_t __qsfp_debugfs_read(struct file *file, char __user *buf,
        int ret;
        int total_read;
 
-       rcu_read_lock();
        if (*ppos + count > QSFP_PAGESIZE * 4) { /* base page + page00-page03 */
                ret = -EINVAL;
                goto _return;
@@ -794,7 +776,6 @@ static ssize_t __qsfp_debugfs_read(struct file *file, char __user *buf,
  _free:
        kfree(buff);
  _return:
-       rcu_read_unlock();
        return ret;
 }
 
@@ -1010,7 +991,6 @@ void hfi1_dbg_ibdev_exit(struct hfi1_ibdev *ibd)
        debugfs_remove_recursive(ibd->hfi1_ibdev_dbg);
 out:
        ibd->hfi1_ibdev_dbg = NULL;
-       synchronize_rcu();
 }
 
 /*
@@ -1035,9 +1015,7 @@ static const char * const hfi1_statnames[] = {
 };
 
 static void *_driver_stats_names_seq_start(struct seq_file *s, loff_t *pos)
-__acquires(RCU)
 {
-       rcu_read_lock();
        if (*pos >= ARRAY_SIZE(hfi1_statnames))
                return NULL;
        return pos;
@@ -1055,9 +1033,7 @@ static void *_driver_stats_names_seq_next(
 }
 
 static void _driver_stats_names_seq_stop(struct seq_file *s, void *v)
-__releases(RCU)
 {
-       rcu_read_unlock();
 }
 
 static int _driver_stats_names_seq_show(struct seq_file *s, void *v)
@@ -1073,9 +1049,7 @@ DEBUGFS_SEQ_FILE_OPEN(driver_stats_names)
 DEBUGFS_FILE_OPS(driver_stats_names);
 
 static void *_driver_stats_seq_start(struct seq_file *s, loff_t *pos)
-__acquires(RCU)
 {
-       rcu_read_lock();
        if (*pos >= ARRAY_SIZE(hfi1_statnames))
                return NULL;
        return pos;
@@ -1090,9 +1064,7 @@ static void *_driver_stats_seq_next(struct seq_file *s, void *v, loff_t *pos)
 }
 
 static void _driver_stats_seq_stop(struct seq_file *s, void *v)
-__releases(RCU)
 {
-       rcu_read_unlock();
 }
 
 static u64 hfi1_sps_ints(void)