#include <linux/fs.h>
#include <linux/fs_stack.h>
-/* does _NOT_ require i_mutex to be held.
+/*
+ * does _NOT_ require i_mutex to be held.
*
* This function cannot be inlined since i_size_{read,write} is rather
* heavy-weight on 32-bit systems
#include "union.h"
-/* return to userspace the branch indices containing the file in question
+/*
+ * return to userspace the branch indices containing the file in question
*
* We use fd_set and therefore we are limited to the number of the branches
* to FD_SETSIZE, which is currently 1024 - plenty for most people
#include "union.h"
-/* 1) Copyup the file
+/*
+ * 1) Copyup the file
* 2) Rename the file to '.unionfs<original inode#><counter>' - obviously
* stolen from NFS's silly rename
*/
return -1;
}
-/* put all references held by upper struct file and free lower file pointer
+/*
+ * put all references held by upper struct file and free lower file pointer
* array
*/
static void cleanup_file(struct file *file)
BUG_ON(sbgen > dgen);
- /* There are two cases we are interested in. The first is if the
+ /*
+ * There are two cases we are interested in. The first is if the
* generation is lower than the super-block. The second is if someone
* has copied up this file from underneath us, we also need to refresh
* things.
unionfs_set_lower_file_idx(file, bindex, hidden_file);
- /* The branchget goes after the open, because otherwise
+ /*
+ * The branchget goes after the open, because otherwise
* we would miss the reference on release.
*/
unionfs_read_lock(inode->i_sb);
bstart = fbstart(file) = dbstart(file->f_dentry);
bend = fbend(file) = dbend(file->f_dentry);
- /* check for the permission for hidden file. If the error is
+ /*
+ * check for the permission for hidden file. If the error is
* COPYUP_ERR, copyup the file.
*/
if (hidden_dentry->d_inode && is_robranch(file->f_dentry)) {
- /* if the open will change the file, copy it up otherwise
+ /*
+ * if the open will change the file, copy it up otherwise
* defer it.
*/
if (hidden_flags & O_TRUNC) {
dget(hidden_dentry);
- /* dentry_open will decrement mnt refcnt if err.
+ /*
+ * dentry_open will decrement mnt refcnt if err.
* otherwise fput() will do an mntput() for us upon file close.
*/
unionfs_mntget(file->f_dentry, bstart);
/* increment, so that we can flush appropriately */
atomic_inc(&UNIONFS_I(dentry->d_inode)->totalopens);
- /* open all directories and make the unionfs file struct point to
+ /*
+ * open all directories and make the unionfs file struct point to
* these hidden file structs
*/
if (S_ISDIR(inode->i_mode))
struct dentry *dentry,
const char *name, int bindex);
-/* For detailed explanation of copyup see:
+/*
+ * For detailed explanation of copyup see:
* Documentation/filesystems/unionfs/concepts.txt
*/
dentry->d_name.len, copyup_file, len);
}
-/* create the new device/file/directory - use copyup_permission to copyup
+/*
+ * create the new device/file/directory - use copyup_permission to copyup
* times, and mode
*
* if the object being copied up is a regular file, the file is only created,
return err;
}
-/* dput the lower references for old and new dentry & clear a lower dentry
+/*
+ * dput the lower references for old and new dentry & clear a lower dentry
* pointer
*/
static void __clear(struct dentry *dentry, struct dentry *old_hidden_dentry,
unionfs_reinterpose(dentry);
goto out_unlock;
- /****/
out_unlink:
- /* copyup failed, because we possibly ran out of space or
+ /*
+ * copyup failed, because we possibly ran out of space or
* quota, or something else happened so let's unlink; we don't
* really care about the return value of vfs_unlink
*/
return err;
}
-/* This function creates a copy of a file represented by 'file' which currently
+/*
+ * This function creates a copy of a file represented by 'file' which currently
* resides in branch 'bstart' to branch 'new_bindex.' The copy will be named
* "name".
*/
return err;
}
-/* This function creates a copy of a file represented by 'file' which currently
+/*
+ * This function creates a copy of a file represented by 'file' which currently
* resides in branch 'bstart' to branch 'new_bindex'.
*/
int copyup_file(struct inode *dir, struct file *file, int bstart,
return err;
}
-/* This function replicates the directory structure upto given dentry in the
+/*
+ * This function replicates the directory structure upto given dentry in the
* bindex branch. Can create directory structure recursively to the right
* also.
*/
loop_start = min(old_bstart, bindex);
loop_end = max(old_bend, bindex);
- /* This loop sets the bstart and bend for the new dentry by
+ /*
+ * This loop sets the bstart and bend for the new dentry by
* traversing from left to right. It also dputs all negative
* dentries except bindex
*/
set_dbend(upper, bindex);
}
-/* This function replicates the directory structure upto given dentry
+/*
+ * This function replicates the directory structure upto given dentry
* in the bindex branch.
*/
static struct dentry *create_parents_named(struct inode *dir,
parent_dentry = dentry;
count = 0;
- /* This loop finds the first parent that exists in the given branch.
+ /*
+ * This loop finds the first parent that exists in the given branch.
* We start building the directory structure from there. At the end
* of the loop, the following should hold:
* - child_dentry is the first nonexistent child
sb = dentry->d_sb;
- /* This is basically while(child_dentry != dentry). This loop is
+ /*
+ * This is basically while(child_dentry != dentry). This loop is
* horrible to follow and should be replaced with cleaner code.
*/
while (1) {
goto out;
} else {
- /* is the name a whiteout of the childname ?
+ /*
+ * is the name a whiteout of the childname ?
* lookup the whiteout child in the underlying file
* system
*/
}
if (hidden_dentry->d_inode) {
- /* since this already exists we dput to avoid
+ /*
+ * since this already exists we dput to avoid
* multiple references on the same dentry
*/
dput(hidden_dentry);
positive = 1;
dgen = atomic_read(&UNIONFS_D(dentry)->generation);
sbgen = atomic_read(&UNIONFS_SB(dentry->d_sb)->generation);
- /* If we are working on an unconnected dentry, then there is no
+ /*
+ * If we are working on an unconnected dentry, then there is no
* revalidation to be done, because this file does not exist within the
* namespace, and Unionfs operates on the namespace, not data.
*/
valid = 0;
goto out;
}
- /* current unionfs_lookup_backend() doesn't return
+ /*
+ * current unionfs_lookup_backend() doesn't return
* a valid dentry
*/
dput(dentry);
return err;
}
-/* This is not meant to be a generic repositioning function. If you do
+/*
+ * This is not meant to be a generic repositioning function. If you do
* things that aren't supported, then we return EINVAL.
*
* What is allowed:
return err;
}
-/* Trimmed directory options, we shouldn't pass everything down since
+/*
+ * Trimmed directory options, we shouldn't pass everything down since
* we don't want to operate on partial directories.
*/
struct file_operations unionfs_dir_fops = {
#include "union.h"
-/* Delete all of the whiteouts in a given directory for rmdir.
+/*
+ * Delete all of the whiteouts in a given directory for rmdir.
*
* hidden directory inode should be locked
*/
}
if (wh_dentry->d_inode) {
- /* .wh.foo has been found. */
- /* First truncate it and then rename it to foo (hence having
+ /*
+ * .wh.foo has been found.
+ * First truncate it and then rename it to foo (hence having
* the same overall effect as a normal create.
*/
struct dentry *hidden_dir_dentry;
/* exit if the error returned was NOT -EROFS */
if (!IS_COPYUP_ERR(err))
goto out;
- /* We were not able to create the file in this
+ /*
+ * We were not able to create the file in this
* branch, so, we try to create it in one branch to
* left
*/
bstart--;
} else {
- /* reset the unionfs dentry to point to the .wh.foo
+ /*
+ * reset the unionfs dentry to point to the .wh.foo
* entry.
*/
for (bindex = bstart; bindex >= 0; bindex--) {
hidden_dentry = unionfs_lower_dentry_idx(dentry, bindex);
if (!hidden_dentry) {
- /* if hidden_dentry is NULL, create the entire
+ /*
+ * if hidden_dentry is NULL, create the entire
* dentry directory structure in branch 'bindex'.
* hidden_dentry will NOT be null when bindex == bstart
* because lookup passed as a negative unionfs dentry
- * pointing to a lone negative underlying dentry */
+ * pointing to a lone negative underlying dentry.
+ */
hidden_dentry = create_parents(parent, dentry, bindex);
if (!hidden_dentry || IS_ERR(hidden_dentry)) {
if (IS_ERR(hidden_dentry))
hidden_new_dentry = unionfs_lower_dentry(new_dentry);
- /* check if whiteout exists in the branch of new dentry, i.e. lookup
+ /*
+ * check if whiteout exists in the branch of new dentry, i.e. lookup
* .wh.foo first. If present, delete it
*/
name = alloc_whname(new_dentry->d_name.name, new_dentry->d_name.len);
hidden_dentry = unionfs_lower_dentry(dentry);
- /* check if whiteout exists in this branch, i.e. lookup .wh.foo
+ /*
+ * check if whiteout exists in this branch, i.e. lookup .wh.foo
* first. If present, delete it
*/
name = alloc_whname(dentry->d_name.name, dentry->d_name.len);
}
}
- /* deleted whiteout if it was present, now do a normal vfs_symlink()
+ /*
+ * deleted whiteout if it was present, now do a normal vfs_symlink()
* with possible recursive directory creation
*/
for (bindex = bstart; bindex >= 0; bindex--) {
hidden_dentry = unionfs_lower_dentry_idx(dentry, bindex);
if (!hidden_dentry) {
- /* if hidden_dentry is NULL, create the entire
+ /*
+ * if hidden_dentry is NULL, create the entire
* dentry directory structure in branch 'bindex'.
* hidden_dentry will NOT be null when bindex ==
* bstart because lookup passed as a negative
kfree(nd_get_link(nd));
}
-/* Basically copied from the kernel vfs permission(), but we've changed
+/*
+ * Basically copied from the kernel vfs permission(), but we've changed
* the following:
* (1) the IS_RDONLY check is skipped, and
* (2) if you set the mount option `mode=nfsro', we assume that -EACCES
if (!hidden_inode)
continue;
- /* check the condition for D-F-D underlying files/directories,
+ /*
+ * check the condition for D-F-D underlying files/directories,
* we dont have to check for files, if we are checking for
* directories.
*/
if (!is_file && !S_ISDIR(hidden_inode->i_mode))
continue;
- /* We use our own special version of permission, such that
+ /*
+ * We use our own special version of permission, such that
* only the first branch returns -EROFS.
*/
err = inode_permission(hidden_inode, mask, nd, bindex);
- /* The permissions are an intersection of the overall directory
+ /*
+ * The permissions are an intersection of the overall directory
* permissions, so we fail if one fails.
*/
if (err)
const char *name;
int namelen;
- /* We should already have a lock on this dentry in the case of a
+ /*
+ * We should already have a lock on this dentry in the case of a
* partial lookup, or a revalidation. Otherwise it is returned from
* new_dentry_private_data already locked.
*/
bopaque = dbopaque(parent_dentry);
BUG_ON(bstart < 0);
- /* It would be ideal if we could convert partial lookups to only have
+ /*
+ * It would be ideal if we could convert partial lookups to only have
* to do this work when they really need to. It could probably improve
* performance quite a bit, and maybe simplify the rest of the code.
*/
goto out_free;
}
- /* Store the first negative dentry specially, because if they
+ /*
+ * Store the first negative dentry specially, because if they
* are all negative we need this for future creates.
*/
if (!hidden_dentry->d_inode) {
if (!first_hidden_dentry && (dbstart(dentry) == -1)) {
first_hidden_dentry = hidden_dentry;
- /* FIXME: following line needs to be changed
+ /*
+ * FIXME: following line needs to be changed
* to allow mountpoint crossing
*/
first_dentry = parent_dentry;
if (dbstart(dentry) == -1)
set_dbstart(dentry, bindex);
unionfs_set_lower_dentry_idx(dentry, bindex, hidden_dentry);
- /* FIXME: the following line needs to get fixed to allow
+ /*
+ * FIXME: the following line needs to get fixed to allow
* mountpoint crossing
*/
unionfs_set_lower_mnt_idx(dentry, bindex,
goto out;
}
- /* FIXME: the following line needs to be changed to allow
+ /*
+ * FIXME: the following line needs to be changed to allow
* mountpoint crossing
*/
first_dentry = dentry;
out_positive:
BUG_ON(dentry_count <= 0);
- /* If we're holding onto the first negative dentry & corresponding
+ /*
+ * If we're holding onto the first negative dentry & corresponding
* vfsmount - throw it out.
*/
dput(first_hidden_dentry);
goto out;
}
- /* This somehow turned positive, so it is as if we had a
+ /*
+ * This somehow turned positive, so it is as if we had a
* negative revalidation.
*/
lookupmode = INTERPOSE_REVAL_NEG;
return -ENOMEM;
}
-/* scan through the lower dentry objects, and set bstart to reflect the
+/*
+ * scan through the lower dentry objects, and set bstart to reflect the
* starting branch
*/
void update_bstart(struct dentry *dentry)
}
BUG_ON(is_negative_dentry);
- /* We allocate our new inode below, by calling iget.
+ /*
+ * We allocate our new inode below, by calling iget.
* iget will call our read_inode which will initialize some
* of the new inode's fields
*/
- /* On revalidate we've already got our own inode and just need
+ /*
+ * On revalidate we've already got our own inode and just need
* to fix it up.
*/
if (flag == INTERPOSE_REVAL) {
S_ISFIFO(hidden_inode->i_mode) || S_ISSOCK(hidden_inode->i_mode))
init_special_inode(inode, hidden_inode->i_mode,
hidden_inode->i_rdev);
- /* Fix our inode's address operations to that of the lower inode
+ /*
+ * Fix our inode's address operations to that of the lower inode
* (Unionfs is FiST-Lite)
*/
if (inode->i_mapping->a_ops != hidden_inode->i_mapping->a_ops)
ibend(inode) = dbend(dentry);
}
-/* make sure the branch we just looked up (nd) makes sense:
+/*
+ * make sure the branch we just looked up (nd) makes sense:
*
* 1) we're not trying to stack unionfs on top of unionfs
* 2) it exists
goto out;
}
- /* Each colon means we have a separator, this is really just a rough
+ /*
+ * Each colon means we have a separator, this is really just a rough
* guess, since strsep will handle empty fields for us.
*/
for (i = 0; options[i]; i++)
kfree(hidden_root_info->lower_paths);
kfree(UNIONFS_SB(sb)->data);
- /* MUST clear the pointers to prevent potential double free if
+ /*
+ * MUST clear the pointers to prevent potential double free if
* the caller dies later on
*/
hidden_root_info->lower_paths = NULL;
if (optarg)
*optarg++ = '\0';
- /* All of our options take an argument now. Insert ones that
+ /*
+ * All of our options take an argument now. Insert ones that
* don't, above this check.
*/
if (!optarg) {
return hidden_root_info;
}
-/* our custom d_alloc_root workalike
+/*
+ * our custom d_alloc_root workalike
*
* we can't use d_alloc_root if we want to use our own interpose function
* unchanged, so we simply call our own "fake" d_alloc_root
/* This file contains the routines for maintaining readdir state. */
-/* There are two structures here, rdstate which is a hash table
+/*
+ * There are two structures here, rdstate which is a hash table
* of the second structure which is a filldir_node.
*/
-/* This is a struct kmem_cache for filldir nodes, because we allocate a lot
+/*
+ * This is a struct kmem_cache for filldir nodes, because we allocate a lot
* of them and they shouldn't waste memory. If the node has a small name
* (as defined by the dentry structure), then we use an inline name to
* preserve kmalloc space.
kmem_cache_destroy(unionfs_filldir_cachep);
}
-/* This is a tuning parameter that tells us roughly how big to make the
+/*
+ * This is a tuning parameter that tells us roughly how big to make the
* hash table in directory entries per page. This isn't perfect, but
* at least we get a hash table size that shouldn't be too overloaded.
* The following averages are based on my home directory.
if (cursor->namelen == namelen && cursor->hash == hash &&
!strncmp(cursor->name, name, namelen)) {
- /* a duplicate exists, and hence no need to create
+ /*
+ * a duplicate exists, and hence no need to create
* entry to the list
*/
found = 1;
- /* if the duplicate is in this branch, then the file
+ /*
+ * if the duplicate is in this branch, then the file
* system is corrupted.
*/
if (cursor->bindex == rdstate->bindex) {
if (err)
goto out_unlock;
- /* ready to whiteout for old_dentry. caller will create the actual
+ /*
+ * ready to whiteout for old_dentry. caller will create the actual
* whiteout, and must dput(*wh_old)
*/
if (wh_old) {
} else
revert = 1;
- /* Unlink all instances of destination that exist to the left of
+ /*
+ * Unlink all instances of destination that exist to the left of
* bstart of source. On error, revert back, goto out.
*/
for (bindex = old_bstart - 1; bindex >= new_bstart; bindex--) {
if (do_copyup != -1) {
for (bindex = do_copyup; bindex >= 0; bindex--) {
- /* copyup the file into some left directory, so that
+ /*
+ * copyup the file into some left directory, so that
* you can rename it
*/
err = copyup_dentry(old_dentry->d_parent->d_inode,
goto revert;
}
- /* Create whiteout for source, only if:
+ /*
+ * Create whiteout for source, only if:
* (1) There is more than one underlying instance of source.
* (2) We did a copy_up
*/
return wh_dentry;
}
-/* We can't copyup a directory, because it may involve huge
+/*
+ * We can't copyup a directory, because it may involve huge
* numbers of children, etc. Doing that in the kernel would
* be bad, so instead we let the userspace recurse and ask us
* to copy up each file separately
/* clear the new_dentry stuff created */
d_drop(new_dentry);
else
- /* force re-lookup since the dir on ro branch is not renamed,
- and hidden dentries still indicate the un-renamed ones. */
+ /*
+ * force re-lookup since the dir on ro branch is not renamed,
+ * and hidden dentries still indicate the un-renamed ones.
+ */
if (S_ISDIR(old_dentry->d_inode->i_mode))
atomic_dec(&UNIONFS_D(old_dentry)->generation);
#include "union.h"
-/* Super-user IO work Queue - sometimes we need to perform actions which
+/*
+ * Super-user IO work Queue - sometimes we need to perform actions which
* would fail due to the unix permissions on the parent directory (e.g.,
* rmdir a directory which appears empty, but in reality contains
* whiteouts).
#include "union.h"
-/* Pass an unionfs dentry and an index. It will try to create a whiteout
+/*
+ * Pass an unionfs dentry and an index. It will try to create a whiteout
* for the filename in dentry, and will try in branch 'index'. On error,
* it will proceed to a branch to the left.
*/
hidden_dentry = unionfs_lower_dentry_idx(dentry, bindex);
if (!hidden_dentry) {
- /* if hidden dentry is not present, create the entire
+ /*
+ * if hidden dentry is not present, create the entire
* hidden dentry directory structure and go ahead.
* Since we want to just create whiteout, we only want
* the parent dentry, and hence get rid of this dentry.
if (IS_ERR(hidden_wh_dentry))
continue;
- /* The whiteout already exists. This used to be impossible, but
+ /*
+ * The whiteout already exists. This used to be impossible, but
* now is possible because of opaqueness.
*/
if (hidden_wh_dentry->d_inode) {
return err;
}
-/* This is a helper function for rename, which ends up with hosed over dentries
+/*
+ * This is a helper function for rename, which ends up with hosed over dentries
* when it needs to revert.
*/
int unionfs_refresh_hidden_dentry(struct dentry *dentry, int bindex)
return err;
}
-/* returns the sum of the n_link values of all the underlying inodes of the
+/*
+ * returns the sum of the n_link values of all the underlying inodes of the
* passed inode
*/
int unionfs_get_nlinks(struct inode *inode)
#include "union.h"
-/* The inode cache is used with alloc_inode for both our inode info and the
+/*
+ * The inode cache is used with alloc_inode for both our inode info and the
* vfs inode.
*/
static struct kmem_cache *unionfs_inode_cachep;
sb->s_fs_info = NULL;
}
-/* Since people use this to answer the "How big of a file can I write?"
+/*
+ * Since people use this to answer the "How big of a file can I write?"
* question, we report the size of the highest priority branch as the size of
* the union.
*/
free_rdstate(rdstate);
}
- /* Decrement a reference to a hidden_inode, which was incremented
+ /*
+ * Decrement a reference to a hidden_inode, which was incremented
* by our read_inode when it was created initially.
*/
bstart = ibstart(inode);
kmem_cache_destroy(unionfs_inode_cachep);
}
-/* Called when we have a dirty inode, right here we only throw out
+/*
+ * Called when we have a dirty inode, right here we only throw out
* parts of our readdir list that are too old.
*/
static int unionfs_write_inode(struct inode *inode, int sync)
int bindex, bstart, bend;
if (!(flags & MNT_FORCE))
- /* we are not being MNT_FORCEd, therefore we should emulate
+ /*
+ * we are not being MNT_FORCEd, therefore we should emulate
* old behaviour
*/
return;
/* unionfs dentry data in memory */
struct unionfs_dentry_info {
- /* The semaphore is used to lock the dentry as soon as we get into a
+ /*
+ * The semaphore is used to lock the dentry as soon as we get into a
* unionfs function from the VFS. Our lock ordering is that children
* go before their parents.
*/
int hash; /* name hash */
int namelen; /* name len since name is not 0 terminated */
- /* we can check for duplicate whiteouts and files in the same branch
+ /*
+ * we can check for duplicate whiteouts and files in the same branch
* in order to return -EIO.
*/
int bindex;
/* partial lookup */
extern int unionfs_partial_lookup(struct dentry *dentry);
-/* Pass an unionfs dentry and an index and it will try to create a whiteout
+/*
+ * Pass an unionfs dentry and an index and it will try to create a whiteout
* in branch 'index'.
*
* On error, it will proceed to a branch to the left
/* What do we use for whiteouts. */
#define UNIONFS_WHPFX ".wh."
#define UNIONFS_WHLEN 4
-/* If a directory contains this file, then it is opaque. We start with the
+/*
+ * If a directory contains this file, then it is opaque. We start with the
* .wh. flag so that it is blocked by lookup.
*/
#define UNIONFS_DIR_OPAQUE_NAME "__dir_opaque"
extern int __parse_branch_mode(const char *name);
extern int parse_branch_mode(const char *name);
-/* These two functions are here because it is kind of daft to copy and paste
+/*
+ * These two functions are here because it is kind of daft to copy and paste
* the contents of the two functions to 32+ places in unionfs
*/
static inline struct dentry *lock_parent(struct dentry *dentry)
vfree(ptr);
}
-/* BKL held by caller.
+/*
+ * BKL held by caller.
* dentry->d_inode->i_mutex locked
*/
ssize_t unionfs_getxattr(struct dentry * dentry, const char *name, void *value,
return err;
}
-/* BKL held by caller.
+/*
+ * BKL held by caller.
* dentry->d_inode->i_mutex locked
*/
int unionfs_setxattr(struct dentry *dentry, const char *name,
return err;
}
-/* BKL held by caller.
+/*
+ * BKL held by caller.
* dentry->d_inode->i_mutex locked
*/
int unionfs_removexattr(struct dentry *dentry, const char *name)
return err;
}
-/* BKL held by caller.
+/*
+ * BKL held by caller.
* dentry->d_inode->i_mutex locked
*/
ssize_t unionfs_listxattr(struct dentry * dentry, char *list, size_t size)
#ifndef _LINUX_FS_STACK_H
#define _LINUX_FS_STACK_H
-/* This file defines generic functions used primarily by stackable
+/*
+ * This file defines generic functions used primarily by stackable
* filesystems; none of these functions require i_mutex to be held.
*/
projects / unionfs-2.6.37.y.git / commitdiff