proc_fops: convert drivers/isdn/ to seq_file

Convert code away from ->read_proc/->write_proc interfaces.  Switch to
proc_create()/proc_create_data() which make addition of proc entries
reliable wrt NULL ->proc_fops, NULL ->data and so on.

Problem with ->read_proc et al is described here commit
786d7e1612f0b0adb6046f19b906609e4fe8b1ba "Fix rmmod/read/write races in
/proc entries"

[akpm@linux-foundation.org: CONFIG_PROC_FS=n build fix]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Tilman Schmidt <tilman@imap.cc>
Signed-off-by: Karsten Keil <keil@b1-systems.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 87 insertions, 111 deletions

diff --git a/drivers/isdn/hardware/eicon/divasproc.c b/drivers/isdn/hardware/eicon/divasproc.c
index 040827288ec9..46d44a942624 100644
--- a/drivers/isdn/hardware/eicon/divasproc.c
+++ b/drivers/isdn/hardware/eicon/divasproc.c
@@ -14,6 +14,7 @@
 #include <linux/kernel.h>
 #include <linux/poll.h>
 #include <linux/proc_fs.h>
+#include <linux/seq_file.h>
 #include <linux/list.h>
 #include <asm/uaccess.h>
 
@@ -141,14 +142,10 @@ void remove_divas_proc(void)
         }
 }
 
-/*
-** write group_optimization 
-*/
-static int
-write_grp_opt(struct file *file, const char __user *buffer, unsigned long count,
-              void *data)
+static ssize_t grp_opt_proc_write(struct file *file, const char __user *buffer,
+                                  size_t count, loff_t *pos)
 {
-        diva_os_xdi_adapter_t *a = (diva_os_xdi_adapter_t *) data;
+        diva_os_xdi_adapter_t *a = PDE(file->f_path.dentry->d_inode)->data;
         PISDN_ADAPTER IoAdapter = IoAdapters[a->controller - 1];
 
         if ((count == 1) || (count == 2)) {
@@ -172,14 +169,10 @@ write_grp_opt(struct file *file, const char __user *buffer, unsigned long count,
         return (-EINVAL);
 }
 
-/*
-** write dynamic_l1_down
-*/
-static int
-write_d_l1_down(struct file *file, const char __user *buffer, unsigned long count,
-                void *data)
+static ssize_t d_l1_down_proc_write(struct file *file, const char __user *buffer,
+                                    size_t count, loff_t *pos)
 {
-        diva_os_xdi_adapter_t *a = (diva_os_xdi_adapter_t *) data;
+        diva_os_xdi_adapter_t *a = PDE(file->f_path.dentry->d_inode)->data;
         PISDN_ADAPTER IoAdapter = IoAdapters[a->controller - 1];
 
         if ((count == 1) || (count == 2)) {
@@ -203,63 +196,62 @@ write_d_l1_down(struct file *file, const char __user *buffer, unsigned long coun
         return (-EINVAL);
 }
 
-
-/*
-** read dynamic_l1_down 
-*/
-static int
-read_d_l1_down(char *page, char **start, off_t off, int count, int *eof,
-               void *data)
+static int d_l1_down_proc_show(struct seq_file *m, void *v)
 {
-        int len = 0;
-        diva_os_xdi_adapter_t *a = (diva_os_xdi_adapter_t *) data;
+        diva_os_xdi_adapter_t *a = m->private;
         PISDN_ADAPTER IoAdapter = IoAdapters[a->controller - 1];
 
-        len += sprintf(page + len, "%s\n",
+        seq_printf(m, "%s\n",
                        (IoAdapter->capi_cfg.
                         cfg_1 & DIVA_XDI_CAPI_CFG_1_DYNAMIC_L1_ON) ? "1" :
                        "0");
+        return 0;
+}
 
-        if (off + count >= len)
-                *eof = 1;
-        if (len < off)
-                return 0;
-        *start = page + off;
-        return ((count < len - off) ? count : len - off);
+static int d_l1_down_proc_open(struct inode *inode, struct file *file)
+{
+        return single_open(file, d_l1_down_proc_show, PDE(inode)->data);
 }
 
-/*
-** read group_optimization
-*/
-static int
-read_grp_opt(char *page, char **start, off_t off, int count, int *eof,
-             void *data)
+static const struct file_operations d_l1_down_proc_fops = {
+        .owner          = THIS_MODULE,
+        .open           = d_l1_down_proc_open,
+        .read           = seq_read,
+        .llseek         = seq_lseek,
+        .release        = single_release,
+        .write          = d_l1_down_proc_write,
+};
+
+static int grp_opt_proc_show(struct seq_file *m, void *v)
 {
-        int len = 0;
-        diva_os_xdi_adapter_t *a = (diva_os_xdi_adapter_t *) data;
+        diva_os_xdi_adapter_t *a = m->private;
         PISDN_ADAPTER IoAdapter = IoAdapters[a->controller - 1];
 
-        len += sprintf(page + len, "%s\n",
+        seq_printf(m, "%s\n",
                        (IoAdapter->capi_cfg.
                         cfg_1 & DIVA_XDI_CAPI_CFG_1_GROUP_POPTIMIZATION_ON)
                        ? "1" : "0");
+        return 0;
+}
 
-        if (off + count >= len)
-                *eof = 1;
-        if (len < off)
-                return 0;
-        *start = page + off;
-        return ((count < len - off) ? count : len - off);
+static int grp_opt_proc_open(struct inode *inode, struct file *file)
+{
+        return single_open(file, grp_opt_proc_show, PDE(inode)->data);
 }
 
-/*
-** info write
-*/
-static int
-info_write(struct file *file, const char __user *buffer, unsigned long count,
-           void *data)
+static const struct file_operations grp_opt_proc_fops = {
+        .owner          = THIS_MODULE,
+        .open           = grp_opt_proc_open,
+        .read           = seq_read,
+        .llseek         = seq_lseek,
+        .release        = single_release,
+        .write          = grp_opt_proc_write,
+};
+
+static ssize_t info_proc_write(struct file *file, const char __user *buffer,
+                               size_t count, loff_t *pos)
 {
-        diva_os_xdi_adapter_t *a = (diva_os_xdi_adapter_t *) data;
+        diva_os_xdi_adapter_t *a = PDE(file->f_path.dentry->d_inode)->data;
         PISDN_ADAPTER IoAdapter = IoAdapters[a->controller - 1];
         char c[4];
 
@@ -277,63 +269,46 @@ info_write(struct file *file, const char __user *buffer, unsigned long count,
         return (-EINVAL);
 }
 
-/*
-** info read
-*/
-static int
-info_read(char *page, char **start, off_t off, int count, int *eof,
-          void *data)
+static int info_proc_show(struct seq_file *m, void *v)
 {
         int i = 0;
-        int len = 0;
         char *p;
         char tmpser[16];
-        diva_os_xdi_adapter_t *a = (diva_os_xdi_adapter_t *) data;
+        diva_os_xdi_adapter_t *a = m->private;
         PISDN_ADAPTER IoAdapter = IoAdapters[a->controller - 1];
 
-        len +=
-            sprintf(page + len, "Name        : %s\n",
-                    IoAdapter->Properties.Name);
-        len += sprintf(page + len, "DSP state   : %08x\n", a->dsp_mask);
-        len += sprintf(page + len, "Channels    : %02d\n",
-                       IoAdapter->Properties.Channels);
-        len += sprintf(page + len, "E. max/used : %03d/%03d\n",
+        seq_printf(m, "Name        : %s\n", IoAdapter->Properties.Name);
+        seq_printf(m, "DSP state   : %08x\n", a->dsp_mask);
+        seq_printf(m, "Channels    : %02d\n", IoAdapter->Properties.Channels);
+        seq_printf(m, "E. max/used : %03d/%03d\n",
                        IoAdapter->e_max, IoAdapter->e_count);
         diva_get_vserial_number(IoAdapter, tmpser);
-        len += sprintf(page + len, "Serial      : %s\n", tmpser);
-        len +=
-            sprintf(page + len, "IRQ         : %d\n",
-                    IoAdapter->irq_info.irq_nr);
-        len += sprintf(page + len, "CardIndex   : %d\n", a->CardIndex);
-        len += sprintf(page + len, "CardOrdinal : %d\n", a->CardOrdinal);
-        len += sprintf(page + len, "Controller  : %d\n", a->controller);
-        len += sprintf(page + len, "Bus-Type    : %s\n",
+        seq_printf(m, "Serial      : %s\n", tmpser);
+        seq_printf(m, "IRQ         : %d\n", IoAdapter->irq_info.irq_nr);
+        seq_printf(m, "CardIndex   : %d\n", a->CardIndex);
+        seq_printf(m, "CardOrdinal : %d\n", a->CardOrdinal);
+        seq_printf(m, "Controller  : %d\n", a->controller);
+        seq_printf(m, "Bus-Type    : %s\n",
                        (a->Bus ==
                         DIVAS_XDI_ADAPTER_BUS_ISA) ? "ISA" : "PCI");
-        len += sprintf(page + len, "Port-Name   : %s\n", a->port_name);
+        seq_printf(m, "Port-Name   : %s\n", a->port_name);
         if (a->Bus == DIVAS_XDI_ADAPTER_BUS_PCI) {
-                len +=
-                    sprintf(page + len, "PCI-bus     : %d\n",
-                            a->resources.pci.bus);
-                len +=
-                    sprintf(page + len, "PCI-func    : %d\n",
-                            a->resources.pci.func);
+                seq_printf(m, "PCI-bus     : %d\n", a->resources.pci.bus);
+                seq_printf(m, "PCI-func    : %d\n", a->resources.pci.func);
                 for (i = 0; i < 8; i++) {
                         if (a->resources.pci.bar[i]) {
-                                len +=
-                                    sprintf(page + len,
+                                seq_printf(m,
                                             "Mem / I/O %d : 0x%x / mapped : 0x%lx",
                                             i, a->resources.pci.bar[i],
                                             (unsigned long) a->resources.
                                             pci.addr[i]);
                                 if (a->resources.pci.length[i]) {
-                                        len +=
-                                            sprintf(page + len,
+                                        seq_printf(m,
                                                     " / length : %d",
                                                     a->resources.pci.
                                                     length[i]);
                                 }
-                                len += sprintf(page + len, "\n");
+                                seq_putc(m, '\n');
                         }
                 }
         }
@@ -353,16 +328,25 @@ info_read(char *page, char **start, off_t off, int count, int *eof,
         } else {
                 p = "ready";
         }
-        len += sprintf(page + len, "State       : %s\n", p);
+        seq_printf(m, "State       : %s\n", p);
 
-        if (off + count >= len)
-                *eof = 1;
-        if (len < off)
-                return 0;
-        *start = page + off;
-        return ((count < len - off) ? count : len - off);
+        return 0;
+}
+
+static int info_proc_open(struct inode *inode, struct file *file)
+{
+        return single_open(file, info_proc_show, PDE(inode)->data);
 }
 
+static const struct file_operations info_proc_fops = {
+        .owner          = THIS_MODULE,
+        .open           = info_proc_open,
+        .read           = seq_read,
+        .llseek         = seq_lseek,
+        .release        = single_release,
+        .write          = info_proc_write,
+};
+
 /*
 ** adapter proc init/de-init
 */
@@ -380,28 +364,20 @@ int create_adapter_proc(diva_os_xdi_adapter_t * a)
                 return (0);
         a->proc_adapter_dir = (void *) de;
 
-        if (!(pe =
-             create_proc_entry(info_proc_name, S_IFREG | S_IRUGO | S_IWUSR, de)))
+        pe = proc_create_data(info_proc_name, S_IRUGO | S_IWUSR, de,
+                              &info_proc_fops, a);
+        if (!pe)
                 return (0);
         a->proc_info = (void *) pe;
-        pe->write_proc = info_write;
-        pe->read_proc = info_read;
-        pe->data = a;
 
-        if ((pe = create_proc_entry(grp_opt_proc_name,
-                               S_IFREG | S_IRUGO | S_IWUSR, de))) {
+        pe = proc_create_data(grp_opt_proc_name, S_IRUGO | S_IWUSR, de,
+                              &grp_opt_proc_fops, a);
+        if (pe)
                 a->proc_grp_opt = (void *) pe;
-                pe->write_proc = write_grp_opt;
-                pe->read_proc = read_grp_opt;
-                pe->data = a;
-        }
-        if ((pe = create_proc_entry(d_l1_down_proc_name,
-                               S_IFREG | S_IRUGO | S_IWUSR, de))) {
+        pe = proc_create_data(d_l1_down_proc_name, S_IRUGO | S_IWUSR, de,
+                              &d_l1_down_proc_fops, a);
+        if (pe)
                 a->proc_d_l1_down = (void *) pe;
-                pe->write_proc = write_d_l1_down;
-                pe->read_proc = read_d_l1_down;
-                pe->data = a;
-        }
 
         DBG_TRC(("proc entry %s created", tmp));