X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=fs%2Fproc%2Fgeneric.c;h=c60d4538ffd3e85b53af54d23ed72ac3e85271e1;hb=refs%2Fheads%2Fvserver;hp=e77cf186e2083ecca38ccb70b4209efb306af70c;hpb=9bf4aaab3e101692164d49b7ca357651eb691cb6;p=linux-2.6.git

diff --git a/fs/proc/generic.c b/fs/proc/generic.c
index e77cf186e..c60d4538f 100644
--- a/fs/proc/generic.c
+++ b/fs/proc/generic.c
@@ -18,10 +18,12 @@
 #include <linux/init.h>
 #include <linux/idr.h>
 #include <linux/namei.h>
-#include <linux/vs_base.h>
+#include <linux/bitops.h>
+#include <linux/spinlock.h>
 #include <linux/vserver/inode.h>
 #include <asm/uaccess.h>
-#include <asm/bitops.h>
+
+#include "internal.h"
 
 static ssize_t proc_file_read(struct file *file, char __user *buf,
 			      size_t nbytes, loff_t *ppos);
@@ -29,6 +31,8 @@ static ssize_t proc_file_write(struct file *file, const char __user *buffer,
 			       size_t count, loff_t *ppos);
 static loff_t proc_file_lseek(struct file *, loff_t, int);
 
+DEFINE_SPINLOCK(proc_subdir_lock);
+
 int proc_match(int len, const char *name, struct proc_dir_entry *de)
 {
 	if (de->namelen != len)
@@ -49,20 +53,32 @@ static ssize_t
 proc_file_read(struct file *file, char __user *buf, size_t nbytes,
 	       loff_t *ppos)
 {
-	struct inode * inode = file->f_dentry->d_inode;
+	struct inode * inode = file->f_path.dentry->d_inode;
 	char 	*page;
 	ssize_t	retval=0;
 	int	eof=0;
 	ssize_t	n, count;
 	char	*start;
 	struct proc_dir_entry * dp;
+	unsigned long long pos;
+
+	/*
+	 * Gaah, please just use "seq_file" instead. The legacy /proc
+	 * interfaces cut loff_t down to off_t for reads, and ignore
+	 * the offset entirely for writes..
+	 */
+	pos = *ppos;
+	if (pos > MAX_NON_LFS)
+		return 0;
+	if (nbytes > MAX_NON_LFS - pos)
+		nbytes = MAX_NON_LFS - pos;
 
 	dp = PDE(inode);
 	if (!(page = (char*) __get_free_page(GFP_KERNEL)))
 		return -ENOMEM;
 
 	while ((nbytes > 0) && !eof) {
-		count = min_t(ssize_t, PROC_BLOCK_SIZE, nbytes);
+		count = min_t(size_t, PROC_BLOCK_SIZE, nbytes);
 
 		start = NULL;
 		if (dp->get_info) {
@@ -188,7 +204,7 @@ static ssize_t
 proc_file_write(struct file *file, const char __user *buffer,
 		size_t count, loff_t *ppos)
 {
-	struct inode *inode = file->f_dentry->d_inode;
+	struct inode *inode = file->f_path.dentry->d_inode;
 	struct proc_dir_entry * dp;
 	
 	dp = PDE(inode);
@@ -204,30 +220,17 @@ proc_file_write(struct file *file, const char __user *buffer,
 static loff_t
 proc_file_lseek(struct file *file, loff_t offset, int orig)
 {
-    lock_kernel();
-
-    switch (orig) {
-    case 0:
-	if (offset < 0)
-	    goto out;
-	file->f_pos = offset;
-	unlock_kernel();
-	return(file->f_pos);
-    case 1:
-	if (offset + file->f_pos < 0)
-	    goto out;
-	file->f_pos += offset;
-	unlock_kernel();
-	return(file->f_pos);
-    case 2:
-	goto out;
-    default:
-	goto out;
-    }
-
-out:
-    unlock_kernel();
-    return -EINVAL;
+	loff_t retval = -EINVAL;
+	switch (orig) {
+	case 1:
+		offset += file->f_pos;
+	/* fallthrough */
+	case 0:
+		if (offset < 0 || offset > MAX_NON_LFS)
+			break;
+		file->f_pos = retval = offset;
+	}
+	return retval;
 }
 
 static int proc_notify_change(struct dentry *dentry, struct iattr *iattr)
@@ -251,6 +254,18 @@ out:
 	return error;
 }
 
+static int proc_getattr(struct vfsmount *mnt, struct dentry *dentry,
+			struct kstat *stat)
+{
+	struct inode *inode = dentry->d_inode;
+	struct proc_dir_entry *de = PROC_I(inode)->pde;
+	if (de && de->nlink)
+		inode->i_nlink = de->nlink;
+
+	generic_fillattr(inode, stat);
+	return 0;
+}
+
 static struct inode_operations proc_file_inode_operations = {
 	.setattr	= proc_notify_change,
 };
@@ -266,7 +281,9 @@ static int xlate_proc_name(const char *name,
 	const char     		*cp = name, *next;
 	struct proc_dir_entry	*de;
 	int			len;
+	int 			rtn = 0;
 
+	spin_lock(&proc_subdir_lock);
 	de = &proc_root;
 	while (1) {
 		next = strchr(cp, '/');
@@ -278,17 +295,21 @@ static int xlate_proc_name(const char *name,
 			if (proc_match(len, cp, de))
 				break;
 		}
-		if (!de)
-			return -ENOENT;
+		if (!de) {
+			rtn = -ENOENT;
+			goto out;
+		}
 		cp += len + 1;
 	}
 	*residual = cp;
 	*ret = de;
-	return 0;
+out:
+	spin_unlock(&proc_subdir_lock);
+	return rtn;
 }
 
 static DEFINE_IDR(proc_inum_idr);
-static spinlock_t proc_inum_lock = SPIN_LOCK_UNLOCKED; /* protects the above */
+static DEFINE_SPINLOCK(proc_inum_lock); /* protects the above */
 
 #define PROC_DYNAMIC_FIRST 0xF0000000UL
 
@@ -331,10 +352,10 @@ static void release_inode_number(unsigned int inum)
 	spin_unlock(&proc_inum_lock);
 }
 
-static int proc_follow_link(struct dentry *dentry, struct nameidata *nd)
+static void *proc_follow_link(struct dentry *dentry, struct nameidata *nd)
 {
 	nd_set_link(nd, PDE(dentry->d_inode)->data);
-	return 0;
+	return NULL;
 }
 
 static struct inode_operations proc_link_inode_operations = {
@@ -353,15 +374,8 @@ static int proc_delete_dentry(struct dentry * dentry)
 	return 1;
 }
 
-static int proc_revalidate_dentry(struct dentry *de, struct nameidata *nd)
-{
-	/* maybe add a check if it's really necessary? */
-	return 0;
-}
-
 static struct dentry_operations proc_dentry_operations =
 {
-	.d_revalidate	= proc_revalidate_dentry,
 	.d_delete	= proc_delete_dentry,
 };
 
@@ -376,6 +390,7 @@ struct dentry *proc_lookup(struct inode * dir, struct dentry *dentry, struct nam
 	int error = -ENOENT;
 
 	lock_kernel();
+	spin_lock(&proc_subdir_lock);
 	de = PDE(dir);
 	if (de) {
 		for (de = de->subdir; de ; de = de->next) {
@@ -386,13 +401,17 @@ struct dentry *proc_lookup(struct inode * dir, struct dentry *dentry, struct nam
 			if (!memcmp(dentry->d_name.name, de->name, de->namelen)) {
 				unsigned int ino = de->low_ino;
 
+				spin_unlock(&proc_subdir_lock);
 				error = -EINVAL;
 				inode = proc_get_inode(dir->i_sb, ino, de);
-				inode->i_xid = vx_current_xid();
+				/* generic proc entries belong to the host */
+				inode->i_tag = 0;
+				spin_lock(&proc_subdir_lock);
 				break;
 			}
 		}
 	}
+	spin_unlock(&proc_subdir_lock);
 	unlock_kernel();
 
 	if (inode) {
@@ -418,7 +437,7 @@ int proc_readdir(struct file * filp,
 	struct proc_dir_entry * de;
 	unsigned int ino;
 	int i;
-	struct inode *inode = filp->f_dentry->d_inode;
+	struct inode *inode = filp->f_path.dentry->d_inode;
 	int ret = 0;
 
 	lock_kernel();
@@ -439,18 +458,20 @@ int proc_readdir(struct file * filp,
 			/* fall through */
 		case 1:
 			if (filldir(dirent, "..", 2, i,
-				    parent_ino(filp->f_dentry),
+				    parent_ino(filp->f_path.dentry),
 				    DT_DIR) < 0)
 				goto out;
 			i++;
 			filp->f_pos++;
 			/* fall through */
 		default:
+			spin_lock(&proc_subdir_lock);
 			de = de->subdir;
 			i -= 2;
 			for (;;) {
 				if (!de) {
 					ret = 1;
+					spin_unlock(&proc_subdir_lock);
 					goto out;
 				}
 				if (!i)
@@ -462,13 +483,17 @@ int proc_readdir(struct file * filp,
 			do {
 				if (!vx_hide_check(0, de->vx_flags))
 					goto skip;
+				/* filldir passes info to user space */
+				spin_unlock(&proc_subdir_lock);
 				if (filldir(dirent, de->name, de->namelen, filp->f_pos,
 					    de->low_ino, de->mode >> 12) < 0)
 					goto out;
+				spin_lock(&proc_subdir_lock);
 			skip:
 				filp->f_pos++;
 				de = de->next;
 			} while (de);
+			spin_unlock(&proc_subdir_lock);
 	}
 	ret = 1;
 out:	unlock_kernel();
@@ -490,6 +515,7 @@ static struct file_operations proc_dir_operations = {
  */
 static struct inode_operations proc_dir_inode_operations = {
 	.lookup		= proc_lookup,
+	.getattr	= proc_getattr,
 	.setattr	= proc_notify_change,
 };
 
@@ -501,9 +527,13 @@ static int proc_register(struct proc_dir_entry * dir, struct proc_dir_entry * dp
 	if (i == 0)
 		return -EAGAIN;
 	dp->low_ino = i;
+
+	spin_lock(&proc_subdir_lock);
 	dp->next = dir->subdir;
 	dp->parent = dir;
 	dir->subdir = dp;
+	spin_unlock(&proc_subdir_lock);
+
 	if (S_ISDIR(dp->mode)) {
 		if (dp->proc_iops == NULL) {
 			dp->proc_fops = &proc_dir_operations;
@@ -535,10 +565,10 @@ static void proc_kill_inodes(struct proc_dir_entry *de)
 	 */
 	file_list_lock();
 	list_for_each(p, &sb->s_files) {
-		struct file * filp = list_entry(p, struct file, f_list);
-		struct dentry * dentry = filp->f_dentry;
+		struct file * filp = list_entry(p, struct file, f_u.fu_list);
+		struct dentry * dentry = filp->f_path.dentry;
 		struct inode * inode;
-		struct file_operations *fops;
+		const struct file_operations *fops;
 
 		if (dentry->d_op != &proc_dentry_operations)
 			continue;
@@ -566,6 +596,11 @@ static struct proc_dir_entry *proc_create(struct proc_dir_entry **parent,
 
 	if (!(*parent) && xlate_proc_name(name, parent, &fn) != 0)
 		goto out;
+
+	/* At this point there must not be any '/' characters beyond *fn */
+	if (strchr(fn, '/'))
+		goto out;
+
 	len = strlen(fn);
 
 	ent = kmalloc(sizeof(struct proc_dir_entry) + len + 1, GFP_KERNEL);
@@ -692,6 +727,8 @@ void remove_proc_entry(const char *name, struct proc_dir_entry *parent)
 	if (!parent && xlate_proc_name(name, &parent, &fn) != 0)
 		goto out;
 	len = strlen(fn);
+
+	spin_lock(&proc_subdir_lock);
 	for (p = &parent->subdir; *p; p=&(*p)->next ) {
 		if (!proc_match(len, fn, *p))
 			continue;
@@ -712,6 +749,7 @@ void remove_proc_entry(const char *name, struct proc_dir_entry *parent)
 		}
 		break;
 	}
+	spin_unlock(&proc_subdir_lock);
 out:
 	return;
 }