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Diffstat (limited to 'fs/proc/generic.c')
-rw-r--r--fs/proc/generic.c186
1 files changed, 139 insertions, 47 deletions
diff --git a/fs/proc/generic.c b/fs/proc/generic.c
index 2078e70e1595..bb1c1625b158 100644
--- a/fs/proc/generic.c
+++ b/fs/proc/generic.c
@@ -25,6 +25,7 @@
#include <linux/spinlock.h>
#include <linux/completion.h>
#include <linux/uaccess.h>
+#include <linux/seq_file.h>
#include "internal.h"
@@ -256,8 +257,7 @@ struct dentry *proc_lookup_de(struct inode *dir, struct dentry *dentry,
if (!inode)
return ERR_PTR(-ENOMEM);
d_set_d_op(dentry, &proc_misc_dentry_ops);
- d_add(dentry, inode);
- return NULL;
+ return d_splice_alias(inode, dentry);
}
read_unlock(&proc_subdir_lock);
return ERR_PTR(-ENOENT);
@@ -346,13 +346,12 @@ static const struct inode_operations proc_dir_inode_operations = {
.setattr = proc_notify_change,
};
-static int proc_register(struct proc_dir_entry * dir, struct proc_dir_entry * dp)
+/* returns the registered entry, or frees dp and returns NULL on failure */
+struct proc_dir_entry *proc_register(struct proc_dir_entry *dir,
+ struct proc_dir_entry *dp)
{
- int ret;
-
- ret = proc_alloc_inum(&dp->low_ino);
- if (ret)
- return ret;
+ if (proc_alloc_inum(&dp->low_ino))
+ goto out_free_entry;
write_lock(&proc_subdir_lock);
dp->parent = dir;
@@ -360,12 +359,16 @@ static int proc_register(struct proc_dir_entry * dir, struct proc_dir_entry * dp
WARN(1, "proc_dir_entry '%s/%s' already registered\n",
dir->name, dp->name);
write_unlock(&proc_subdir_lock);
- proc_free_inum(dp->low_ino);
- return -EEXIST;
+ goto out_free_inum;
}
write_unlock(&proc_subdir_lock);
- return 0;
+ return dp;
+out_free_inum:
+ proc_free_inum(dp->low_ino);
+out_free_entry:
+ pde_free(dp);
+ return NULL;
}
static struct proc_dir_entry *__proc_create(struct proc_dir_entry **parent,
@@ -406,7 +409,7 @@ static struct proc_dir_entry *__proc_create(struct proc_dir_entry **parent,
if (!ent)
goto out;
- if (qstr.len + 1 <= sizeof(ent->inline_name)) {
+ if (qstr.len + 1 <= SIZEOF_PDE_INLINE_NAME) {
ent->name = ent->inline_name;
} else {
ent->name = kmalloc(qstr.len + 1, GFP_KERNEL);
@@ -443,10 +446,7 @@ struct proc_dir_entry *proc_symlink(const char *name,
if (ent->data) {
strcpy((char*)ent->data,dest);
ent->proc_iops = &proc_link_inode_operations;
- if (proc_register(parent, ent) < 0) {
- pde_free(ent);
- ent = NULL;
- }
+ ent = proc_register(parent, ent);
} else {
pde_free(ent);
ent = NULL;
@@ -470,11 +470,9 @@ struct proc_dir_entry *proc_mkdir_data(const char *name, umode_t mode,
ent->proc_fops = &proc_dir_operations;
ent->proc_iops = &proc_dir_inode_operations;
parent->nlink++;
- if (proc_register(parent, ent) < 0) {
- pde_free(ent);
+ ent = proc_register(parent, ent);
+ if (!ent)
parent->nlink--;
- ent = NULL;
- }
}
return ent;
}
@@ -505,47 +503,47 @@ struct proc_dir_entry *proc_create_mount_point(const char *name)
ent->proc_fops = NULL;
ent->proc_iops = NULL;
parent->nlink++;
- if (proc_register(parent, ent) < 0) {
- pde_free(ent);
+ ent = proc_register(parent, ent);
+ if (!ent)
parent->nlink--;
- ent = NULL;
- }
}
return ent;
}
EXPORT_SYMBOL(proc_create_mount_point);
-struct proc_dir_entry *proc_create_data(const char *name, umode_t mode,
- struct proc_dir_entry *parent,
- const struct file_operations *proc_fops,
- void *data)
+struct proc_dir_entry *proc_create_reg(const char *name, umode_t mode,
+ struct proc_dir_entry **parent, void *data)
{
- struct proc_dir_entry *pde;
+ struct proc_dir_entry *p;
+
if ((mode & S_IFMT) == 0)
mode |= S_IFREG;
-
- if (!S_ISREG(mode)) {
- WARN_ON(1); /* use proc_mkdir() */
+ if ((mode & S_IALLUGO) == 0)
+ mode |= S_IRUGO;
+ if (WARN_ON_ONCE(!S_ISREG(mode)))
return NULL;
+
+ p = __proc_create(parent, name, mode, 1);
+ if (p) {
+ p->proc_iops = &proc_file_inode_operations;
+ p->data = data;
}
+ return p;
+}
+
+struct proc_dir_entry *proc_create_data(const char *name, umode_t mode,
+ struct proc_dir_entry *parent,
+ const struct file_operations *proc_fops, void *data)
+{
+ struct proc_dir_entry *p;
BUG_ON(proc_fops == NULL);
- if ((mode & S_IALLUGO) == 0)
- mode |= S_IRUGO;
- pde = __proc_create(&parent, name, mode, 1);
- if (!pde)
- goto out;
- pde->proc_fops = proc_fops;
- pde->data = data;
- pde->proc_iops = &proc_file_inode_operations;
- if (proc_register(parent, pde) < 0)
- goto out_free;
- return pde;
-out_free:
- pde_free(pde);
-out:
- return NULL;
+ p = proc_create_reg(name, mode, &parent, data);
+ if (!p)
+ return NULL;
+ p->proc_fops = proc_fops;
+ return proc_register(parent, p);
}
EXPORT_SYMBOL(proc_create_data);
@@ -557,6 +555,76 @@ struct proc_dir_entry *proc_create(const char *name, umode_t mode,
}
EXPORT_SYMBOL(proc_create);
+static int proc_seq_open(struct inode *inode, struct file *file)
+{
+ struct proc_dir_entry *de = PDE(inode);
+
+ if (de->state_size)
+ return seq_open_private(file, de->seq_ops, de->state_size);
+ return seq_open(file, de->seq_ops);
+}
+
+static int proc_seq_release(struct inode *inode, struct file *file)
+{
+ struct proc_dir_entry *de = PDE(inode);
+
+ if (de->state_size)
+ return seq_release_private(inode, file);
+ return seq_release(inode, file);
+}
+
+static const struct file_operations proc_seq_fops = {
+ .open = proc_seq_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = proc_seq_release,
+};
+
+struct proc_dir_entry *proc_create_seq_private(const char *name, umode_t mode,
+ struct proc_dir_entry *parent, const struct seq_operations *ops,
+ unsigned int state_size, void *data)
+{
+ struct proc_dir_entry *p;
+
+ p = proc_create_reg(name, mode, &parent, data);
+ if (!p)
+ return NULL;
+ p->proc_fops = &proc_seq_fops;
+ p->seq_ops = ops;
+ p->state_size = state_size;
+ return proc_register(parent, p);
+}
+EXPORT_SYMBOL(proc_create_seq_private);
+
+static int proc_single_open(struct inode *inode, struct file *file)
+{
+ struct proc_dir_entry *de = PDE(inode);
+
+ return single_open(file, de->single_show, de->data);
+}
+
+static const struct file_operations proc_single_fops = {
+ .open = proc_single_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+struct proc_dir_entry *proc_create_single_data(const char *name, umode_t mode,
+ struct proc_dir_entry *parent,
+ int (*show)(struct seq_file *, void *), void *data)
+{
+ struct proc_dir_entry *p;
+
+ p = proc_create_reg(name, mode, &parent, data);
+ if (!p)
+ return NULL;
+ p->proc_fops = &proc_single_fops;
+ p->single_show = show;
+ return proc_register(parent, p);
+}
+EXPORT_SYMBOL(proc_create_single_data);
+
void proc_set_size(struct proc_dir_entry *de, loff_t size)
{
de->size = size;
@@ -681,3 +749,27 @@ void *PDE_DATA(const struct inode *inode)
return __PDE_DATA(inode);
}
EXPORT_SYMBOL(PDE_DATA);
+
+/*
+ * Pull a user buffer into memory and pass it to the file's write handler if
+ * one is supplied. The ->write() method is permitted to modify the
+ * kernel-side buffer.
+ */
+ssize_t proc_simple_write(struct file *f, const char __user *ubuf, size_t size,
+ loff_t *_pos)
+{
+ struct proc_dir_entry *pde = PDE(file_inode(f));
+ char *buf;
+ int ret;
+
+ if (!pde->write)
+ return -EACCES;
+ if (size == 0 || size > PAGE_SIZE - 1)
+ return -EINVAL;
+ buf = memdup_user_nul(ubuf, size);
+ if (IS_ERR(buf))
+ return PTR_ERR(buf);
+ ret = pde->write(f, buf, size);
+ kfree(buf);
+ return ret == 0 ? size : ret;
+}