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Commit b04a2342 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs 

Pull overlayfs updates from Miklos Szeredi:

 - Report constant st_ino values across copy-up even if underlying
   layers are on different filesystems, but using different st_dev
   values for each layer.

   Ideally we'd report the same st_dev across the overlay, and it's
   possible to do for filesystems that use only 32bits for st_ino by
   unifying the inum space. It would be nice if it wasn't a choice of 32
   or 64, rather filesystems could report their current maximum (that
   could change on resize, so it wouldn't be set in stone).

 - miscellaneus fixes and a cleanup of ovl_fill_super(), that was long
   overdue.

 - created a path_put_init() helper that clears out the pointers after
   putting the ref.

   I think this could be useful elsewhere, so added it to <linux/path.h>

* 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs: (30 commits)
  ovl: remove unneeded arg from ovl_verify_origin()
  ovl: Put upperdentry if ovl_check_origin() fails
  ovl: rename ufs to ofs
  ovl: clean up getting lower layers
  ovl: clean up workdir creation
  ovl: clean up getting upper layer
  ovl: move ovl_get_workdir() and ovl_get_lower_layers()
  ovl: reduce the number of arguments for ovl_workdir_create()
  ovl: change order of setup in ovl_fill_super()
  ovl: factor out ovl_free_fs() helper
  ovl: grab reference to workbasedir early
  ovl: split out ovl_get_indexdir() from ovl_fill_super()
  ovl: split out ovl_get_lower_layers() from ovl_fill_super()
  ovl: split out ovl_get_workdir() from ovl_fill_super()
  ovl: split out ovl_get_upper() from ovl_fill_super()
  ovl: split out ovl_get_lowerstack() from ovl_fill_super()
  ovl: split out ovl_get_workpath() from ovl_fill_super()
  ovl: split out ovl_get_upperpath() from ovl_fill_super()
  ovl: use path_put_init() in error paths for ovl_fill_super()
  vfs: add path_put_init()
  ...
parents 5a3e0b19 d9768076

fs/overlayfs/copy_up.c

+6 −2
Original line number Diff line number Diff line
@@ -22,7 +22,6 @@ 
#include <linux/ratelimit.h>

#include <linux/exportfs.h>

#include "overlayfs.h"

#include "ovl_entry.h"



#define OVL_COPY_UP_CHUNK_SIZE (1 << 20)
@@ -486,6 +485,7 @@ static int ovl_copy_up_inode(struct ovl_copy_up_ctx *c, struct dentry *temp) 
static int ovl_copy_up_locked(struct ovl_copy_up_ctx *c)

{

	struct inode *udir = c->destdir->d_inode;

	struct inode *inode;

	struct dentry *newdentry = NULL;

	struct dentry *temp = NULL;

	int err;
@@ -508,7 +508,11 @@ static int ovl_copy_up_locked(struct ovl_copy_up_ctx *c) 
	if (err)

		goto out_cleanup;



	ovl_inode_update(d_inode(c->dentry), newdentry);

	inode = d_inode(c->dentry);

	ovl_inode_update(inode, newdentry);

	if (S_ISDIR(inode->i_mode))

		ovl_set_flag(OVL_WHITEOUTS, inode);



out:

	dput(temp);

	return err;

fs/overlayfs/dir.c

+16 −9
Original line number Diff line number Diff line
@@ -181,6 +181,11 @@ static bool ovl_type_origin(struct dentry *dentry) 
	return OVL_TYPE_ORIGIN(ovl_path_type(dentry));

}



static bool ovl_may_have_whiteouts(struct dentry *dentry)

{

	return ovl_test_flag(OVL_WHITEOUTS, d_inode(dentry));

}



static int ovl_create_upper(struct dentry *dentry, struct inode *inode,

			    struct cattr *attr, struct dentry *hardlink)

{
@@ -300,7 +305,6 @@ static struct dentry *ovl_check_empty_and_clear(struct dentry *dentry) 
{

	int err;

	struct dentry *ret = NULL;

	enum ovl_path_type type = ovl_path_type(dentry);

	LIST_HEAD(list);



	err = ovl_check_empty_dir(dentry, &list);
@@ -313,13 +317,13 @@ static struct dentry *ovl_check_empty_and_clear(struct dentry *dentry) 
	 * When removing an empty opaque directory, then it makes no sense to

	 * replace it with an exact replica of itself.

	 *

	 * If no upperdentry then skip clearing whiteouts.

	 * If upperdentry has whiteouts, clear them.

	 *

	 * Can race with copy-up, since we don't hold the upperdir mutex.

	 * Doesn't matter, since copy-up can't create a non-empty directory

	 * from an empty one.

	 */

	if (OVL_TYPE_UPPER(type) && OVL_TYPE_MERGE(type))

	if (!list_empty(&list))

		ret = ovl_clear_empty(dentry, &list);



out_free:
@@ -698,8 +702,9 @@ static int ovl_remove_upper(struct dentry *dentry, bool is_dir) 
	struct dentry *opaquedir = NULL;

	int err;



	/* Redirect dir can be !ovl_lower_positive && OVL_TYPE_MERGE */

	if (is_dir && ovl_dentry_get_redirect(dentry)) {

	/* Redirect/origin dir can be !ovl_lower_positive && not clean */

	if (is_dir && (ovl_dentry_get_redirect(dentry) ||

		       ovl_may_have_whiteouts(dentry))) {

		opaquedir = ovl_check_empty_and_clear(dentry);

		err = PTR_ERR(opaquedir);

		if (IS_ERR(opaquedir))
@@ -946,7 +951,8 @@ static int ovl_rename(struct inode *olddir, struct dentry *old, 


	old_cred = ovl_override_creds(old->d_sb);



	if (overwrite && new_is_dir && ovl_type_merge_or_lower(new)) {

	if (overwrite && new_is_dir && (ovl_type_merge_or_lower(new) ||

					ovl_may_have_whiteouts(new))) {

		opaquedir = ovl_check_empty_and_clear(new);

		err = PTR_ERR(opaquedir);

		if (IS_ERR(opaquedir)) {
@@ -1069,9 +1075,10 @@ static int ovl_rename(struct inode *olddir, struct dentry *old, 
			drop_nlink(d_inode(new));

	}



	ovl_dentry_version_inc(old->d_parent,

			       !overwrite && ovl_type_origin(new));

	ovl_dentry_version_inc(new->d_parent, ovl_type_origin(old));

	ovl_dentry_version_inc(old->d_parent, ovl_type_origin(old) ||

			       (!overwrite && ovl_type_origin(new)));

	ovl_dentry_version_inc(new->d_parent, ovl_type_origin(old) ||

			       (d_inode(new) && ovl_type_origin(new)));



out_dput:

	dput(newdentry);

fs/overlayfs/inode.c

+50 −13
Original line number Diff line number Diff line
@@ -15,6 +15,14 @@ 
#include <linux/ratelimit.h>

#include "overlayfs.h"





static dev_t ovl_get_pseudo_dev(struct dentry *dentry)

{

	struct ovl_entry *oe = dentry->d_fsdata;



	return oe->lowerstack[0].layer->pseudo_dev;

}



int ovl_setattr(struct dentry *dentry, struct iattr *attr)

{

	int err;
@@ -66,6 +74,7 @@ int ovl_getattr(const struct path *path, struct kstat *stat, 
	struct path realpath;

	const struct cred *old_cred;

	bool is_dir = S_ISDIR(dentry->d_inode->i_mode);

	bool samefs = ovl_same_sb(dentry->d_sb);

	int err;



	type = ovl_path_real(dentry, &realpath);
@@ -75,16 +84,13 @@ int ovl_getattr(const struct path *path, struct kstat *stat, 
		goto out;



	/*

	 * When all layers are on the same fs, all real inode number are

	 * unique, so we use the overlay st_dev, which is friendly to du -x.

	 *

	 * We also use st_ino of the copy up origin, if we know it.

	 * This guaranties constant st_dev/st_ino across copy up.

	 * For non-dir or same fs, we use st_ino of the copy up origin, if we

	 * know it. This guaranties constant st_dev/st_ino across copy up.

	 *

	 * If filesystem supports NFS export ops, this also guaranties

	 * persistent st_ino across mount cycle.

	 */

	if (ovl_same_sb(dentry->d_sb)) {

	if (!is_dir || samefs) {

		if (OVL_TYPE_ORIGIN(type)) {

			struct kstat lowerstat;

			u32 lowermask = STATX_INO | (!is_dir ? STATX_NLINK : 0);
@@ -95,7 +101,6 @@ int ovl_getattr(const struct path *path, struct kstat *stat, 
			if (err)

				goto out;



			WARN_ON_ONCE(stat->dev != lowerstat.dev);

			/*

			 * Lower hardlinks may be broken on copy up to different

			 * upper files, so we cannot use the lower origin st_ino
@@ -107,17 +112,36 @@ int ovl_getattr(const struct path *path, struct kstat *stat, 
			if (is_dir || lowerstat.nlink == 1 ||

			    ovl_test_flag(OVL_INDEX, d_inode(dentry)))

				stat->ino = lowerstat.ino;



			if (samefs)

				WARN_ON_ONCE(stat->dev != lowerstat.dev);

			else

				stat->dev = ovl_get_pseudo_dev(dentry);

		}

		if (samefs) {

			/*

			 * When all layers are on the same fs, all real inode

			 * number are unique, so we use the overlay st_dev,

			 * which is friendly to du -x.

			 */

			stat->dev = dentry->d_sb->s_dev;

	} else if (is_dir) {

		} else if (!OVL_TYPE_UPPER(type)) {

			/*

			 * For non-samefs setup, to make sure that st_dev/st_ino

			 * pair is unique across the system, we use a unique

			 * anonymous st_dev for lower layer inode.

			 */

			stat->dev = ovl_get_pseudo_dev(dentry);

		}

	} else {

		/*

		 * If not all layers are on the same fs the pair {real st_ino;

		 * overlay st_dev} is not unique, so use the non persistent

		 * overlay st_ino.

		 *

		 * Always use the overlay st_dev for directories, so 'find

		 * -xdev' will scan the entire overlay mount and won't cross the

		 * overlay mount boundaries.

		 *

		 * If not all layers are on the same fs the pair {real st_ino;

		 * overlay st_dev} is not unique, so use the non persistent

		 * overlay st_ino for directories.

		 */

		stat->dev = dentry->d_sb->s_dev;

		stat->ino = dentry->d_inode->i_ino;
@@ -409,6 +433,7 @@ static inline void ovl_lockdep_annotate_inode_mutex_key(struct inode *inode) 
#ifdef CONFIG_LOCKDEP

	static struct lock_class_key ovl_i_mutex_key[OVL_MAX_NESTING];

	static struct lock_class_key ovl_i_mutex_dir_key[OVL_MAX_NESTING];

	static struct lock_class_key ovl_i_lock_key[OVL_MAX_NESTING];



	int depth = inode->i_sb->s_stack_depth - 1;
@@ -419,6 +444,8 @@ static inline void ovl_lockdep_annotate_inode_mutex_key(struct inode *inode) 
		lockdep_set_class(&inode->i_rwsem, &ovl_i_mutex_dir_key[depth]);

	else

		lockdep_set_class(&inode->i_rwsem, &ovl_i_mutex_key[depth]);



	lockdep_set_class(&OVL_I(inode)->lock, &ovl_i_lock_key[depth]);

#endif

}
@@ -657,6 +684,16 @@ struct inode *ovl_get_inode(struct dentry *dentry, struct dentry *upperdentry, 
	if (upperdentry && ovl_is_impuredir(upperdentry))

		ovl_set_flag(OVL_IMPURE, inode);



	/* Check for non-merge dir that may have whiteouts */

	if (S_ISDIR(realinode->i_mode)) {

		struct ovl_entry *oe = dentry->d_fsdata;



		if (((upperdentry && lowerdentry) || oe->numlower > 1) ||

		    ovl_check_origin_xattr(upperdentry ?: lowerdentry)) {

			ovl_set_flag(OVL_WHITEOUTS, inode);

		}

	}



	if (inode->i_state & I_NEW)

		unlock_new_inode(inode);

out:

fs/overlayfs/namei.c

+34 −25
Original line number Diff line number Diff line
@@ -15,7 +15,6 @@ 
#include <linux/mount.h>

#include <linux/exportfs.h>

#include "overlayfs.h"

#include "ovl_entry.h"



struct ovl_lookup_data {

	struct qstr name;
@@ -286,16 +285,15 @@ static int ovl_lookup_layer(struct dentry *base, struct ovl_lookup_data *d, 




static int ovl_check_origin(struct dentry *upperdentry,

			    struct path *lowerstack, unsigned int numlower,

			    struct path **stackp, unsigned int *ctrp)

			    struct ovl_path *lower, unsigned int numlower,

			    struct ovl_path **stackp, unsigned int *ctrp)

{

	struct vfsmount *mnt;

	struct dentry *origin = NULL;

	int i;





	for (i = 0; i < numlower; i++) {

		mnt = lowerstack[i].mnt;

		mnt = lower[i].layer->mnt;

		origin = ovl_get_origin(upperdentry, mnt);

		if (IS_ERR(origin))

			return PTR_ERR(origin);
@@ -309,12 +307,12 @@ static int ovl_check_origin(struct dentry *upperdentry, 


	BUG_ON(*ctrp);

	if (!*stackp)

		*stackp = kmalloc(sizeof(struct path), GFP_KERNEL);

		*stackp = kmalloc(sizeof(struct ovl_path), GFP_KERNEL);

	if (!*stackp) {

		dput(origin);

		return -ENOMEM;

	}

	**stackp = (struct path) { .dentry = origin, .mnt = mnt };

	**stackp = (struct ovl_path){.dentry = origin, .layer = lower[i].layer};

	*ctrp = 1;



	return 0;
@@ -350,8 +348,8 @@ static int ovl_verify_origin_fh(struct dentry *dentry, const struct ovl_fh *fh) 
 *

 * Return 0 on match, -ESTALE on mismatch, < 0 on error.

 */

int ovl_verify_origin(struct dentry *dentry, struct vfsmount *mnt,

		      struct dentry *origin, bool is_upper, bool set)

int ovl_verify_origin(struct dentry *dentry, struct dentry *origin,

		      bool is_upper, bool set)

{

	struct inode *inode;

	struct ovl_fh *fh;
@@ -384,13 +382,13 @@ int ovl_verify_origin(struct dentry *dentry, struct vfsmount *mnt, 
 * OVL_XATTR_ORIGIN and that origin file handle can be decoded to lower path.

 * Return 0 on match, -ESTALE on mismatch or stale origin, < 0 on error.

 */

int ovl_verify_index(struct dentry *index, struct path *lowerstack,

int ovl_verify_index(struct dentry *index, struct ovl_path *lower,

		     unsigned int numlower)

{

	struct ovl_fh *fh = NULL;

	size_t len;

	struct path origin = { };

	struct path *stack = &origin;

	struct ovl_path origin = { };

	struct ovl_path *stack = &origin;

	unsigned int ctr = 0;

	int err;
@@ -429,7 +427,7 @@ int ovl_verify_index(struct dentry *index, struct path *lowerstack, 
	if (err)

		goto fail;



	err = ovl_check_origin(index, lowerstack, numlower, &stack, &ctr);

	err = ovl_check_origin(index, lower, numlower, &stack, &ctr);

	if (!err && !ctr)

		err = -ESTALE;

	if (err)
@@ -568,11 +566,24 @@ int ovl_path_next(int idx, struct dentry *dentry, struct path *path) 
		idx++;

	}

	BUG_ON(idx > oe->numlower);

	*path = oe->lowerstack[idx - 1];

	path->dentry = oe->lowerstack[idx - 1].dentry;

	path->mnt = oe->lowerstack[idx - 1].layer->mnt;



	return (idx < oe->numlower) ? idx + 1 : -1;

}



static int ovl_find_layer(struct ovl_fs *ofs, struct ovl_path *path)

{

	int i;



	for (i = 0; i < ofs->numlower; i++) {

		if (ofs->lower_layers[i].mnt == path->layer->mnt)

			break;

	}



	return i;

}



struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry,

			  unsigned int flags)

{
@@ -581,7 +592,7 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry, 
	struct ovl_fs *ofs = dentry->d_sb->s_fs_info;

	struct ovl_entry *poe = dentry->d_parent->d_fsdata;

	struct ovl_entry *roe = dentry->d_sb->s_root->d_fsdata;

	struct path *stack = NULL;

	struct ovl_path *stack = NULL;

	struct dentry *upperdir, *upperdentry = NULL;

	struct dentry *index = NULL;

	unsigned int ctr = 0;
@@ -630,7 +641,7 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry, 
			err = ovl_check_origin(upperdentry, roe->lowerstack,

					       roe->numlower, &stack, &ctr);

			if (err)

				goto out;

				goto out_put_upper;

		}



		if (d.redirect) {
@@ -646,17 +657,17 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry, 


	if (!d.stop && poe->numlower) {

		err = -ENOMEM;

		stack = kcalloc(ofs->numlower, sizeof(struct path),

		stack = kcalloc(ofs->numlower, sizeof(struct ovl_path),

				GFP_KERNEL);

		if (!stack)

			goto out_put_upper;

	}



	for (i = 0; !d.stop && i < poe->numlower; i++) {

		struct path lowerpath = poe->lowerstack[i];

		struct ovl_path lower = poe->lowerstack[i];



		d.last = i == poe->numlower - 1;

		err = ovl_lookup_layer(lowerpath.dentry, &d, &this);

		err = ovl_lookup_layer(lower.dentry, &d, &this);

		if (err)

			goto out_put;
@@ -664,7 +675,7 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry, 
			continue;



		stack[ctr].dentry = this;

		stack[ctr].mnt = lowerpath.mnt;

		stack[ctr].layer = lower.layer;

		ctr++;



		if (d.stop)
@@ -674,10 +685,8 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry, 
			poe = roe;



			/* Find the current layer on the root dentry */

			for (i = 0; i < poe->numlower; i++)

				if (poe->lowerstack[i].mnt == lowerpath.mnt)

					break;

			if (WARN_ON(i == poe->numlower))

			i = ovl_find_layer(ofs, &lower);

			if (WARN_ON(i == ofs->numlower))

				break;

		}

	}
@@ -700,7 +709,7 @@ struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry, 
		goto out_put;



	oe->opaque = upperopaque;

	memcpy(oe->lowerstack, stack, sizeof(struct path) * ctr);

	memcpy(oe->lowerstack, stack, sizeof(struct ovl_path) * ctr);

	dentry->d_fsdata = oe;



	if (upperdentry)

fs/overlayfs/overlayfs.h

+9 −4
Original line number Diff line number Diff line
@@ -9,6 +9,7 @@ 


#include <linux/kernel.h>

#include <linux/uuid.h>

#include "ovl_entry.h"



enum ovl_path_type {

	__OVL_PATH_UPPER	= (1 << 0),
@@ -28,7 +29,10 @@ enum ovl_path_type { 
#define OVL_XATTR_NLINK OVL_XATTR_PREFIX "nlink"



enum ovl_flag {

	/* Pure upper dir that may contain non pure upper entries */

	OVL_IMPURE,

	/* Non-merge dir that may contain whiteout entries */

	OVL_WHITEOUTS,

	OVL_INDEX,

};
@@ -223,6 +227,7 @@ bool ovl_is_whiteout(struct dentry *dentry); 
struct file *ovl_path_open(struct path *path, int flags);

int ovl_copy_up_start(struct dentry *dentry);

void ovl_copy_up_end(struct dentry *dentry);

bool ovl_check_origin_xattr(struct dentry *dentry);

bool ovl_check_dir_xattr(struct dentry *dentry, const char *name);

int ovl_check_setxattr(struct dentry *dentry, struct dentry *upperdentry,

		       const char *name, const void *value, size_t size,
@@ -244,9 +249,9 @@ static inline bool ovl_is_impuredir(struct dentry *dentry) 




/* namei.c */

int ovl_verify_origin(struct dentry *dentry, struct vfsmount *mnt,

		      struct dentry *origin, bool is_upper, bool set);

int ovl_verify_index(struct dentry *index, struct path *lowerstack,

int ovl_verify_origin(struct dentry *dentry, struct dentry *origin,

		      bool is_upper, bool set);

int ovl_verify_index(struct dentry *index, struct ovl_path *lower,

		     unsigned int numlower);

int ovl_get_index_name(struct dentry *origin, struct qstr *name);

int ovl_path_next(int idx, struct dentry *dentry, struct path *path);
@@ -263,7 +268,7 @@ int ovl_check_d_type_supported(struct path *realpath); 
void ovl_workdir_cleanup(struct inode *dir, struct vfsmount *mnt,

			 struct dentry *dentry, int level);

int ovl_indexdir_cleanup(struct dentry *dentry, struct vfsmount *mnt,

			 struct path *lowerstack, unsigned int numlower);

			 struct ovl_path *lower, unsigned int numlower);



/* inode.c */

int ovl_set_nlink_upper(struct dentry *dentry);