771 lines
26 KiB
C
771 lines
26 KiB
C
/* SPDX-License-Identifier: GPL-2.0-only */
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/*
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*
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* Copyright (C) 2011 Novell Inc.
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*/
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#include <linux/kernel.h>
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#include <linux/uuid.h>
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#include <linux/fs.h>
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#include <linux/namei.h>
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#include <linux/posix_acl.h>
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#include <linux/posix_acl_xattr.h>
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#include "ovl_entry.h"
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#undef pr_fmt
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#define pr_fmt(fmt) "overlayfs: " fmt
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enum ovl_path_type {
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__OVL_PATH_UPPER = (1 << 0),
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__OVL_PATH_MERGE = (1 << 1),
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__OVL_PATH_ORIGIN = (1 << 2),
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};
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#define OVL_TYPE_UPPER(type) ((type) & __OVL_PATH_UPPER)
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#define OVL_TYPE_MERGE(type) ((type) & __OVL_PATH_MERGE)
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#define OVL_TYPE_ORIGIN(type) ((type) & __OVL_PATH_ORIGIN)
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#define OVL_XATTR_NAMESPACE "overlay."
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#define OVL_XATTR_TRUSTED_PREFIX XATTR_TRUSTED_PREFIX OVL_XATTR_NAMESPACE
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#define OVL_XATTR_USER_PREFIX XATTR_USER_PREFIX OVL_XATTR_NAMESPACE
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enum ovl_xattr {
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OVL_XATTR_OPAQUE,
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OVL_XATTR_REDIRECT,
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OVL_XATTR_ORIGIN,
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OVL_XATTR_IMPURE,
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OVL_XATTR_NLINK,
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OVL_XATTR_UPPER,
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OVL_XATTR_METACOPY,
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OVL_XATTR_PROTATTR,
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};
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enum ovl_inode_flag {
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/* Pure upper dir that may contain non pure upper entries */
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OVL_IMPURE,
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/* Non-merge dir that may contain whiteout entries */
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OVL_WHITEOUTS,
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OVL_INDEX,
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OVL_UPPERDATA,
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/* Inode number will remain constant over copy up. */
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OVL_CONST_INO,
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};
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enum ovl_entry_flag {
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OVL_E_UPPER_ALIAS,
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OVL_E_OPAQUE,
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OVL_E_CONNECTED,
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};
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enum {
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OVL_REDIRECT_OFF, /* "off" mode is never used. In effect */
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OVL_REDIRECT_FOLLOW, /* ...it translates to either "follow" */
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OVL_REDIRECT_NOFOLLOW, /* ...or "nofollow". */
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OVL_REDIRECT_ON,
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};
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enum {
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OVL_XINO_OFF,
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OVL_XINO_AUTO,
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OVL_XINO_ON,
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};
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/*
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* The tuple (fh,uuid) is a universal unique identifier for a copy up origin,
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* where:
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* origin.fh - exported file handle of the lower file
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* origin.uuid - uuid of the lower filesystem
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*/
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#define OVL_FH_VERSION 0
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#define OVL_FH_MAGIC 0xfb
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/* CPU byte order required for fid decoding: */
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#define OVL_FH_FLAG_BIG_ENDIAN (1 << 0)
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#define OVL_FH_FLAG_ANY_ENDIAN (1 << 1)
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/* Is the real inode encoded in fid an upper inode? */
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#define OVL_FH_FLAG_PATH_UPPER (1 << 2)
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#define OVL_FH_FLAG_ALL (OVL_FH_FLAG_BIG_ENDIAN | OVL_FH_FLAG_ANY_ENDIAN | \
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OVL_FH_FLAG_PATH_UPPER)
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#if defined(__LITTLE_ENDIAN)
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#define OVL_FH_FLAG_CPU_ENDIAN 0
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#elif defined(__BIG_ENDIAN)
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#define OVL_FH_FLAG_CPU_ENDIAN OVL_FH_FLAG_BIG_ENDIAN
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#else
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#error Endianness not defined
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#endif
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/* The type used to be returned by overlay exportfs for misaligned fid */
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#define OVL_FILEID_V0 0xfb
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/* The type returned by overlay exportfs for 32bit aligned fid */
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#define OVL_FILEID_V1 0xf8
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/* On-disk format for "origin" file handle */
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struct ovl_fb {
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u8 version; /* 0 */
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u8 magic; /* 0xfb */
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u8 len; /* size of this header + size of fid */
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u8 flags; /* OVL_FH_FLAG_* */
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u8 type; /* fid_type of fid */
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uuid_t uuid; /* uuid of filesystem */
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u32 fid[]; /* file identifier should be 32bit aligned in-memory */
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} __packed;
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/* In-memory and on-wire format for overlay file handle */
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struct ovl_fh {
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u8 padding[3]; /* make sure fb.fid is 32bit aligned */
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union {
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struct ovl_fb fb;
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DECLARE_FLEX_ARRAY(u8, buf);
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};
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} __packed;
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#define OVL_FH_WIRE_OFFSET offsetof(struct ovl_fh, fb)
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#define OVL_FH_LEN(fh) (OVL_FH_WIRE_OFFSET + (fh)->fb.len)
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#define OVL_FH_FID_OFFSET (OVL_FH_WIRE_OFFSET + \
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offsetof(struct ovl_fb, fid))
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extern const char *const ovl_xattr_table[][2];
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static inline const char *ovl_xattr(struct ovl_fs *ofs, enum ovl_xattr ox)
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{
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return ovl_xattr_table[ox][ofs->config.userxattr];
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}
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/*
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* When changing ownership of an upper object map the intended ownership
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* according to the upper layer's idmapping. When an upper mount idmaps files
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* that are stored on-disk as owned by id 1001 to id 1000 this means stat on
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* this object will report it as being owned by id 1000 when calling stat via
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* the upper mount.
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* In order to change ownership of an object so stat reports id 1000 when
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* called on an idmapped upper mount the value written to disk - i.e., the
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* value stored in ia_*id - must 1001. The mount mapping helper will thus take
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* care to map 1000 to 1001.
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* The mnt idmapping helpers are nops if the upper layer isn't idmapped.
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*/
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static inline int ovl_do_notify_change(struct ovl_fs *ofs,
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struct dentry *upperdentry,
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struct iattr *attr)
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{
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return notify_change(ovl_upper_mnt_idmap(ofs), upperdentry, attr, NULL);
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}
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static inline int ovl_do_rmdir(struct ovl_fs *ofs,
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struct inode *dir, struct dentry *dentry)
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{
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int err = vfs_rmdir(ovl_upper_mnt_idmap(ofs), dir, dentry);
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pr_debug("rmdir(%pd2) = %i\n", dentry, err);
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return err;
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}
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static inline int ovl_do_unlink(struct ovl_fs *ofs, struct inode *dir,
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struct dentry *dentry)
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{
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int err = vfs_unlink(ovl_upper_mnt_idmap(ofs), dir, dentry, NULL);
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pr_debug("unlink(%pd2) = %i\n", dentry, err);
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return err;
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}
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static inline int ovl_do_link(struct ovl_fs *ofs, struct dentry *old_dentry,
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struct inode *dir, struct dentry *new_dentry)
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{
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int err = vfs_link(old_dentry, ovl_upper_mnt_idmap(ofs), dir,
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new_dentry, NULL);
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pr_debug("link(%pd2, %pd2) = %i\n", old_dentry, new_dentry, err);
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return err;
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}
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static inline int ovl_do_create(struct ovl_fs *ofs,
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struct inode *dir, struct dentry *dentry,
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umode_t mode)
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{
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int err = vfs_create(ovl_upper_mnt_idmap(ofs), dir, dentry, mode, true);
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pr_debug("create(%pd2, 0%o) = %i\n", dentry, mode, err);
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return err;
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}
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static inline int ovl_do_mkdir(struct ovl_fs *ofs,
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struct inode *dir, struct dentry *dentry,
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umode_t mode)
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{
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int err = vfs_mkdir(ovl_upper_mnt_idmap(ofs), dir, dentry, mode);
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pr_debug("mkdir(%pd2, 0%o) = %i\n", dentry, mode, err);
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return err;
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}
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static inline int ovl_do_mknod(struct ovl_fs *ofs,
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struct inode *dir, struct dentry *dentry,
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umode_t mode, dev_t dev)
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{
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int err = vfs_mknod(ovl_upper_mnt_idmap(ofs), dir, dentry, mode, dev);
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pr_debug("mknod(%pd2, 0%o, 0%o) = %i\n", dentry, mode, dev, err);
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return err;
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}
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static inline int ovl_do_symlink(struct ovl_fs *ofs,
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struct inode *dir, struct dentry *dentry,
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const char *oldname)
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{
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int err = vfs_symlink(ovl_upper_mnt_idmap(ofs), dir, dentry, oldname);
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pr_debug("symlink(\"%s\", %pd2) = %i\n", oldname, dentry, err);
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return err;
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}
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static inline ssize_t ovl_do_getxattr(const struct path *path, const char *name,
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void *value, size_t size)
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{
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int err, len;
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WARN_ON(path->dentry->d_sb != path->mnt->mnt_sb);
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err = vfs_getxattr(mnt_idmap(path->mnt), path->dentry,
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name, value, size);
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len = (value && err > 0) ? err : 0;
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pr_debug("getxattr(%pd2, \"%s\", \"%*pE\", %zu, 0) = %i\n",
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path->dentry, name, min(len, 48), value, size, err);
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return err;
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}
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static inline ssize_t ovl_getxattr_upper(struct ovl_fs *ofs,
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struct dentry *upperdentry,
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enum ovl_xattr ox, void *value,
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size_t size)
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{
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struct path upperpath = {
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.dentry = upperdentry,
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.mnt = ovl_upper_mnt(ofs),
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};
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return ovl_do_getxattr(&upperpath, ovl_xattr(ofs, ox), value, size);
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}
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static inline ssize_t ovl_path_getxattr(struct ovl_fs *ofs,
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const struct path *path,
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enum ovl_xattr ox, void *value,
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size_t size)
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{
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return ovl_do_getxattr(path, ovl_xattr(ofs, ox), value, size);
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}
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static inline int ovl_do_setxattr(struct ovl_fs *ofs, struct dentry *dentry,
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const char *name, const void *value,
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size_t size, int flags)
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{
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int err = vfs_setxattr(ovl_upper_mnt_idmap(ofs), dentry, name,
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value, size, flags);
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pr_debug("setxattr(%pd2, \"%s\", \"%*pE\", %zu, %d) = %i\n",
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dentry, name, min((int)size, 48), value, size, flags, err);
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return err;
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}
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static inline int ovl_setxattr(struct ovl_fs *ofs, struct dentry *dentry,
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enum ovl_xattr ox, const void *value,
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size_t size)
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{
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return ovl_do_setxattr(ofs, dentry, ovl_xattr(ofs, ox), value, size, 0);
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}
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static inline int ovl_do_removexattr(struct ovl_fs *ofs, struct dentry *dentry,
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const char *name)
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{
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int err = vfs_removexattr(ovl_upper_mnt_idmap(ofs), dentry, name);
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pr_debug("removexattr(%pd2, \"%s\") = %i\n", dentry, name, err);
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return err;
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}
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static inline int ovl_removexattr(struct ovl_fs *ofs, struct dentry *dentry,
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enum ovl_xattr ox)
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{
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return ovl_do_removexattr(ofs, dentry, ovl_xattr(ofs, ox));
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}
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static inline int ovl_do_set_acl(struct ovl_fs *ofs, struct dentry *dentry,
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const char *acl_name, struct posix_acl *acl)
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{
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return vfs_set_acl(ovl_upper_mnt_idmap(ofs), dentry, acl_name, acl);
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}
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static inline int ovl_do_remove_acl(struct ovl_fs *ofs, struct dentry *dentry,
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const char *acl_name)
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{
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return vfs_remove_acl(ovl_upper_mnt_idmap(ofs), dentry, acl_name);
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}
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static inline int ovl_do_rename(struct ovl_fs *ofs, struct inode *olddir,
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struct dentry *olddentry, struct inode *newdir,
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struct dentry *newdentry, unsigned int flags)
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{
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int err;
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struct renamedata rd = {
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.old_mnt_idmap = ovl_upper_mnt_idmap(ofs),
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.old_dir = olddir,
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.old_dentry = olddentry,
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.new_mnt_idmap = ovl_upper_mnt_idmap(ofs),
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.new_dir = newdir,
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.new_dentry = newdentry,
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.flags = flags,
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};
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pr_debug("rename(%pd2, %pd2, 0x%x)\n", olddentry, newdentry, flags);
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err = vfs_rename(&rd);
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if (err) {
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pr_debug("...rename(%pd2, %pd2, ...) = %i\n",
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olddentry, newdentry, err);
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}
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return err;
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}
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static inline int ovl_do_whiteout(struct ovl_fs *ofs,
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struct inode *dir, struct dentry *dentry)
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{
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int err = vfs_whiteout(ovl_upper_mnt_idmap(ofs), dir, dentry);
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pr_debug("whiteout(%pd2) = %i\n", dentry, err);
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return err;
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}
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static inline struct file *ovl_do_tmpfile(struct ovl_fs *ofs,
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struct dentry *dentry, umode_t mode)
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{
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struct path path = { .mnt = ovl_upper_mnt(ofs), .dentry = dentry };
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struct file *file = kernel_tmpfile_open(ovl_upper_mnt_idmap(ofs), &path,
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mode, O_LARGEFILE | O_WRONLY,
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current_cred());
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int err = PTR_ERR_OR_ZERO(file);
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pr_debug("tmpfile(%pd2, 0%o) = %i\n", dentry, mode, err);
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return file;
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}
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static inline struct dentry *ovl_lookup_upper(struct ovl_fs *ofs,
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const char *name,
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struct dentry *base, int len)
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{
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return lookup_one(ovl_upper_mnt_idmap(ofs), name, base, len);
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}
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static inline bool ovl_open_flags_need_copy_up(int flags)
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{
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if (!flags)
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return false;
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return ((OPEN_FMODE(flags) & FMODE_WRITE) || (flags & O_TRUNC));
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}
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/* util.c */
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int ovl_want_write(struct dentry *dentry);
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void ovl_drop_write(struct dentry *dentry);
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struct dentry *ovl_workdir(struct dentry *dentry);
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const struct cred *ovl_override_creds(struct super_block *sb);
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int ovl_can_decode_fh(struct super_block *sb);
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struct dentry *ovl_indexdir(struct super_block *sb);
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bool ovl_index_all(struct super_block *sb);
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bool ovl_verify_lower(struct super_block *sb);
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struct ovl_path *ovl_stack_alloc(unsigned int n);
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void ovl_stack_cpy(struct ovl_path *dst, struct ovl_path *src, unsigned int n);
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void ovl_stack_put(struct ovl_path *stack, unsigned int n);
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void ovl_stack_free(struct ovl_path *stack, unsigned int n);
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struct ovl_entry *ovl_alloc_entry(unsigned int numlower);
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void ovl_free_entry(struct ovl_entry *oe);
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bool ovl_dentry_remote(struct dentry *dentry);
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void ovl_dentry_update_reval(struct dentry *dentry, struct dentry *realdentry);
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void ovl_dentry_init_reval(struct dentry *dentry, struct dentry *upperdentry,
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struct ovl_entry *oe);
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void ovl_dentry_init_flags(struct dentry *dentry, struct dentry *upperdentry,
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struct ovl_entry *oe, unsigned int mask);
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bool ovl_dentry_weird(struct dentry *dentry);
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enum ovl_path_type ovl_path_type(struct dentry *dentry);
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void ovl_path_upper(struct dentry *dentry, struct path *path);
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void ovl_path_lower(struct dentry *dentry, struct path *path);
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void ovl_path_lowerdata(struct dentry *dentry, struct path *path);
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struct inode *ovl_i_path_real(struct inode *inode, struct path *path);
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enum ovl_path_type ovl_path_real(struct dentry *dentry, struct path *path);
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enum ovl_path_type ovl_path_realdata(struct dentry *dentry, struct path *path);
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struct dentry *ovl_dentry_upper(struct dentry *dentry);
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struct dentry *ovl_dentry_lower(struct dentry *dentry);
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struct dentry *ovl_dentry_lowerdata(struct dentry *dentry);
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int ovl_dentry_set_lowerdata(struct dentry *dentry, struct ovl_path *datapath);
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const struct ovl_layer *ovl_i_layer_lower(struct inode *inode);
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const struct ovl_layer *ovl_layer_lower(struct dentry *dentry);
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struct dentry *ovl_dentry_real(struct dentry *dentry);
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struct dentry *ovl_i_dentry_upper(struct inode *inode);
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struct inode *ovl_inode_upper(struct inode *inode);
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struct inode *ovl_inode_lower(struct inode *inode);
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struct inode *ovl_inode_lowerdata(struct inode *inode);
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struct inode *ovl_inode_real(struct inode *inode);
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struct inode *ovl_inode_realdata(struct inode *inode);
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const char *ovl_lowerdata_redirect(struct inode *inode);
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struct ovl_dir_cache *ovl_dir_cache(struct inode *inode);
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void ovl_set_dir_cache(struct inode *inode, struct ovl_dir_cache *cache);
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void ovl_dentry_set_flag(unsigned long flag, struct dentry *dentry);
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void ovl_dentry_clear_flag(unsigned long flag, struct dentry *dentry);
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bool ovl_dentry_test_flag(unsigned long flag, struct dentry *dentry);
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bool ovl_dentry_is_opaque(struct dentry *dentry);
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bool ovl_dentry_is_whiteout(struct dentry *dentry);
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void ovl_dentry_set_opaque(struct dentry *dentry);
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bool ovl_dentry_has_upper_alias(struct dentry *dentry);
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void ovl_dentry_set_upper_alias(struct dentry *dentry);
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bool ovl_dentry_needs_data_copy_up(struct dentry *dentry, int flags);
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bool ovl_dentry_needs_data_copy_up_locked(struct dentry *dentry, int flags);
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bool ovl_has_upperdata(struct inode *inode);
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void ovl_set_upperdata(struct inode *inode);
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const char *ovl_dentry_get_redirect(struct dentry *dentry);
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void ovl_dentry_set_redirect(struct dentry *dentry, const char *redirect);
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void ovl_inode_update(struct inode *inode, struct dentry *upperdentry);
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void ovl_dir_modified(struct dentry *dentry, bool impurity);
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u64 ovl_inode_version_get(struct inode *inode);
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bool ovl_is_whiteout(struct dentry *dentry);
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struct file *ovl_path_open(const struct path *path, int flags);
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int ovl_copy_up_start(struct dentry *dentry, int flags);
|
|
void ovl_copy_up_end(struct dentry *dentry);
|
|
bool ovl_already_copied_up(struct dentry *dentry, int flags);
|
|
bool ovl_path_check_dir_xattr(struct ovl_fs *ofs, const struct path *path,
|
|
enum ovl_xattr ox);
|
|
bool ovl_path_check_origin_xattr(struct ovl_fs *ofs, const struct path *path);
|
|
|
|
static inline bool ovl_check_origin_xattr(struct ovl_fs *ofs,
|
|
struct dentry *upperdentry)
|
|
{
|
|
struct path upperpath = {
|
|
.dentry = upperdentry,
|
|
.mnt = ovl_upper_mnt(ofs),
|
|
};
|
|
return ovl_path_check_origin_xattr(ofs, &upperpath);
|
|
}
|
|
|
|
int ovl_check_setxattr(struct ovl_fs *ofs, struct dentry *upperdentry,
|
|
enum ovl_xattr ox, const void *value, size_t size,
|
|
int xerr);
|
|
int ovl_set_impure(struct dentry *dentry, struct dentry *upperdentry);
|
|
bool ovl_inuse_trylock(struct dentry *dentry);
|
|
void ovl_inuse_unlock(struct dentry *dentry);
|
|
bool ovl_is_inuse(struct dentry *dentry);
|
|
bool ovl_need_index(struct dentry *dentry);
|
|
int ovl_nlink_start(struct dentry *dentry);
|
|
void ovl_nlink_end(struct dentry *dentry);
|
|
int ovl_lock_rename_workdir(struct dentry *workdir, struct dentry *upperdir);
|
|
int ovl_check_metacopy_xattr(struct ovl_fs *ofs, const struct path *path);
|
|
bool ovl_is_metacopy_dentry(struct dentry *dentry);
|
|
char *ovl_get_redirect_xattr(struct ovl_fs *ofs, const struct path *path, int padding);
|
|
int ovl_sync_status(struct ovl_fs *ofs);
|
|
|
|
static inline void ovl_set_flag(unsigned long flag, struct inode *inode)
|
|
{
|
|
set_bit(flag, &OVL_I(inode)->flags);
|
|
}
|
|
|
|
static inline void ovl_clear_flag(unsigned long flag, struct inode *inode)
|
|
{
|
|
clear_bit(flag, &OVL_I(inode)->flags);
|
|
}
|
|
|
|
static inline bool ovl_test_flag(unsigned long flag, struct inode *inode)
|
|
{
|
|
return test_bit(flag, &OVL_I(inode)->flags);
|
|
}
|
|
|
|
static inline bool ovl_is_impuredir(struct super_block *sb,
|
|
struct dentry *upperdentry)
|
|
{
|
|
struct ovl_fs *ofs = OVL_FS(sb);
|
|
struct path upperpath = {
|
|
.dentry = upperdentry,
|
|
.mnt = ovl_upper_mnt(ofs),
|
|
};
|
|
|
|
return ovl_path_check_dir_xattr(ofs, &upperpath, OVL_XATTR_IMPURE);
|
|
}
|
|
|
|
static inline bool ovl_redirect_follow(struct ovl_fs *ofs)
|
|
{
|
|
return ofs->config.redirect_mode != OVL_REDIRECT_NOFOLLOW;
|
|
}
|
|
|
|
static inline bool ovl_redirect_dir(struct ovl_fs *ofs)
|
|
{
|
|
return ofs->config.redirect_mode == OVL_REDIRECT_ON;
|
|
}
|
|
|
|
/*
|
|
* With xino=auto, we do best effort to keep all inodes on same st_dev and
|
|
* d_ino consistent with st_ino.
|
|
* With xino=on, we do the same effort but we warn if we failed.
|
|
*/
|
|
static inline bool ovl_xino_warn(struct ovl_fs *ofs)
|
|
{
|
|
return ofs->config.xino == OVL_XINO_ON;
|
|
}
|
|
|
|
/*
|
|
* To avoid regressions in existing setups with overlay lower offline changes,
|
|
* we allow lower changes only if none of the new features are used.
|
|
*/
|
|
static inline bool ovl_allow_offline_changes(struct ovl_fs *ofs)
|
|
{
|
|
return (!ofs->config.index && !ofs->config.metacopy &&
|
|
!ovl_redirect_dir(ofs) && !ovl_xino_warn(ofs));
|
|
}
|
|
|
|
/* All layers on same fs? */
|
|
static inline bool ovl_same_fs(struct ovl_fs *ofs)
|
|
{
|
|
return ofs->xino_mode == 0;
|
|
}
|
|
|
|
/* All overlay inodes have same st_dev? */
|
|
static inline bool ovl_same_dev(struct ovl_fs *ofs)
|
|
{
|
|
return ofs->xino_mode >= 0;
|
|
}
|
|
|
|
static inline unsigned int ovl_xino_bits(struct ovl_fs *ofs)
|
|
{
|
|
return ovl_same_dev(ofs) ? ofs->xino_mode : 0;
|
|
}
|
|
|
|
static inline void ovl_inode_lock(struct inode *inode)
|
|
{
|
|
mutex_lock(&OVL_I(inode)->lock);
|
|
}
|
|
|
|
static inline int ovl_inode_lock_interruptible(struct inode *inode)
|
|
{
|
|
return mutex_lock_interruptible(&OVL_I(inode)->lock);
|
|
}
|
|
|
|
static inline void ovl_inode_unlock(struct inode *inode)
|
|
{
|
|
mutex_unlock(&OVL_I(inode)->lock);
|
|
}
|
|
|
|
|
|
/* namei.c */
|
|
int ovl_check_fb_len(struct ovl_fb *fb, int fb_len);
|
|
|
|
static inline int ovl_check_fh_len(struct ovl_fh *fh, int fh_len)
|
|
{
|
|
if (fh_len < sizeof(struct ovl_fh))
|
|
return -EINVAL;
|
|
|
|
return ovl_check_fb_len(&fh->fb, fh_len - OVL_FH_WIRE_OFFSET);
|
|
}
|
|
|
|
struct dentry *ovl_decode_real_fh(struct ovl_fs *ofs, struct ovl_fh *fh,
|
|
struct vfsmount *mnt, bool connected);
|
|
int ovl_check_origin_fh(struct ovl_fs *ofs, struct ovl_fh *fh, bool connected,
|
|
struct dentry *upperdentry, struct ovl_path **stackp);
|
|
int ovl_verify_set_fh(struct ovl_fs *ofs, struct dentry *dentry,
|
|
enum ovl_xattr ox, struct dentry *real, bool is_upper,
|
|
bool set);
|
|
struct dentry *ovl_index_upper(struct ovl_fs *ofs, struct dentry *index,
|
|
bool connected);
|
|
int ovl_verify_index(struct ovl_fs *ofs, struct dentry *index);
|
|
int ovl_get_index_name(struct ovl_fs *ofs, struct dentry *origin,
|
|
struct qstr *name);
|
|
struct dentry *ovl_get_index_fh(struct ovl_fs *ofs, struct ovl_fh *fh);
|
|
struct dentry *ovl_lookup_index(struct ovl_fs *ofs, struct dentry *upper,
|
|
struct dentry *origin, bool verify);
|
|
int ovl_path_next(int idx, struct dentry *dentry, struct path *path);
|
|
int ovl_maybe_lookup_lowerdata(struct dentry *dentry);
|
|
struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry,
|
|
unsigned int flags);
|
|
bool ovl_lower_positive(struct dentry *dentry);
|
|
|
|
static inline int ovl_verify_origin(struct ovl_fs *ofs, struct dentry *upper,
|
|
struct dentry *origin, bool set)
|
|
{
|
|
return ovl_verify_set_fh(ofs, upper, OVL_XATTR_ORIGIN, origin,
|
|
false, set);
|
|
}
|
|
|
|
static inline int ovl_verify_upper(struct ovl_fs *ofs, struct dentry *index,
|
|
struct dentry *upper, bool set)
|
|
{
|
|
return ovl_verify_set_fh(ofs, index, OVL_XATTR_UPPER, upper, true, set);
|
|
}
|
|
|
|
/* readdir.c */
|
|
extern const struct file_operations ovl_dir_operations;
|
|
struct file *ovl_dir_real_file(const struct file *file, bool want_upper);
|
|
int ovl_check_empty_dir(struct dentry *dentry, struct list_head *list);
|
|
void ovl_cleanup_whiteouts(struct ovl_fs *ofs, struct dentry *upper,
|
|
struct list_head *list);
|
|
void ovl_cache_free(struct list_head *list);
|
|
void ovl_dir_cache_free(struct inode *inode);
|
|
int ovl_check_d_type_supported(const struct path *realpath);
|
|
int ovl_workdir_cleanup(struct ovl_fs *ofs, struct inode *dir,
|
|
struct vfsmount *mnt, struct dentry *dentry, int level);
|
|
int ovl_indexdir_cleanup(struct ovl_fs *ofs);
|
|
|
|
/*
|
|
* Can we iterate real dir directly?
|
|
*
|
|
* Non-merge dir may contain whiteouts from a time it was a merge upper, before
|
|
* lower dir was removed under it and possibly before it was rotated from upper
|
|
* to lower layer.
|
|
*/
|
|
static inline bool ovl_dir_is_real(struct inode *dir)
|
|
{
|
|
return !ovl_test_flag(OVL_WHITEOUTS, dir);
|
|
}
|
|
|
|
/* inode.c */
|
|
int ovl_set_nlink_upper(struct dentry *dentry);
|
|
int ovl_set_nlink_lower(struct dentry *dentry);
|
|
unsigned int ovl_get_nlink(struct ovl_fs *ofs, struct dentry *lowerdentry,
|
|
struct dentry *upperdentry,
|
|
unsigned int fallback);
|
|
int ovl_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
|
|
struct iattr *attr);
|
|
int ovl_getattr(struct mnt_idmap *idmap, const struct path *path,
|
|
struct kstat *stat, u32 request_mask, unsigned int flags);
|
|
int ovl_permission(struct mnt_idmap *idmap, struct inode *inode,
|
|
int mask);
|
|
int ovl_xattr_set(struct dentry *dentry, struct inode *inode, const char *name,
|
|
const void *value, size_t size, int flags);
|
|
int ovl_xattr_get(struct dentry *dentry, struct inode *inode, const char *name,
|
|
void *value, size_t size);
|
|
ssize_t ovl_listxattr(struct dentry *dentry, char *list, size_t size);
|
|
|
|
#ifdef CONFIG_FS_POSIX_ACL
|
|
struct posix_acl *do_ovl_get_acl(struct mnt_idmap *idmap,
|
|
struct inode *inode, int type,
|
|
bool rcu, bool noperm);
|
|
static inline struct posix_acl *ovl_get_inode_acl(struct inode *inode, int type,
|
|
bool rcu)
|
|
{
|
|
return do_ovl_get_acl(&nop_mnt_idmap, inode, type, rcu, true);
|
|
}
|
|
static inline struct posix_acl *ovl_get_acl(struct mnt_idmap *idmap,
|
|
struct dentry *dentry, int type)
|
|
{
|
|
return do_ovl_get_acl(idmap, d_inode(dentry), type, false, false);
|
|
}
|
|
int ovl_set_acl(struct mnt_idmap *idmap, struct dentry *dentry,
|
|
struct posix_acl *acl, int type);
|
|
struct posix_acl *ovl_get_acl_path(const struct path *path,
|
|
const char *acl_name, bool noperm);
|
|
#else
|
|
#define ovl_get_inode_acl NULL
|
|
#define ovl_get_acl NULL
|
|
#define ovl_set_acl NULL
|
|
static inline struct posix_acl *ovl_get_acl_path(const struct path *path,
|
|
const char *acl_name,
|
|
bool noperm)
|
|
{
|
|
return NULL;
|
|
}
|
|
#endif
|
|
|
|
int ovl_update_time(struct inode *inode, struct timespec64 *ts, int flags);
|
|
bool ovl_is_private_xattr(struct super_block *sb, const char *name);
|
|
|
|
struct ovl_inode_params {
|
|
struct inode *newinode;
|
|
struct dentry *upperdentry;
|
|
struct ovl_entry *oe;
|
|
bool index;
|
|
char *redirect;
|
|
char *lowerdata_redirect;
|
|
};
|
|
void ovl_inode_init(struct inode *inode, struct ovl_inode_params *oip,
|
|
unsigned long ino, int fsid);
|
|
struct inode *ovl_new_inode(struct super_block *sb, umode_t mode, dev_t rdev);
|
|
struct inode *ovl_lookup_inode(struct super_block *sb, struct dentry *real,
|
|
bool is_upper);
|
|
bool ovl_lookup_trap_inode(struct super_block *sb, struct dentry *dir);
|
|
struct inode *ovl_get_trap_inode(struct super_block *sb, struct dentry *dir);
|
|
struct inode *ovl_get_inode(struct super_block *sb,
|
|
struct ovl_inode_params *oip);
|
|
void ovl_copyattr(struct inode *to);
|
|
|
|
/* vfs inode flags copied from real to ovl inode */
|
|
#define OVL_COPY_I_FLAGS_MASK (S_SYNC | S_NOATIME | S_APPEND | S_IMMUTABLE)
|
|
/* vfs inode flags read from overlay.protattr xattr to ovl inode */
|
|
#define OVL_PROT_I_FLAGS_MASK (S_APPEND | S_IMMUTABLE)
|
|
|
|
/*
|
|
* fileattr flags copied from lower to upper inode on copy up.
|
|
* We cannot copy up immutable/append-only flags, because that would prevent
|
|
* linking temp inode to upper dir, so we store them in xattr instead.
|
|
*/
|
|
#define OVL_COPY_FS_FLAGS_MASK (FS_SYNC_FL | FS_NOATIME_FL)
|
|
#define OVL_COPY_FSX_FLAGS_MASK (FS_XFLAG_SYNC | FS_XFLAG_NOATIME)
|
|
#define OVL_PROT_FS_FLAGS_MASK (FS_APPEND_FL | FS_IMMUTABLE_FL)
|
|
#define OVL_PROT_FSX_FLAGS_MASK (FS_XFLAG_APPEND | FS_XFLAG_IMMUTABLE)
|
|
|
|
void ovl_check_protattr(struct inode *inode, struct dentry *upper);
|
|
int ovl_set_protattr(struct inode *inode, struct dentry *upper,
|
|
struct fileattr *fa);
|
|
|
|
static inline void ovl_copyflags(struct inode *from, struct inode *to)
|
|
{
|
|
unsigned int mask = OVL_COPY_I_FLAGS_MASK;
|
|
|
|
inode_set_flags(to, from->i_flags & mask, mask);
|
|
}
|
|
|
|
/* dir.c */
|
|
extern const struct inode_operations ovl_dir_inode_operations;
|
|
int ovl_cleanup_and_whiteout(struct ovl_fs *ofs, struct inode *dir,
|
|
struct dentry *dentry);
|
|
struct ovl_cattr {
|
|
dev_t rdev;
|
|
umode_t mode;
|
|
const char *link;
|
|
struct dentry *hardlink;
|
|
};
|
|
|
|
#define OVL_CATTR(m) (&(struct ovl_cattr) { .mode = (m) })
|
|
|
|
int ovl_mkdir_real(struct ovl_fs *ofs, struct inode *dir,
|
|
struct dentry **newdentry, umode_t mode);
|
|
struct dentry *ovl_create_real(struct ovl_fs *ofs,
|
|
struct inode *dir, struct dentry *newdentry,
|
|
struct ovl_cattr *attr);
|
|
int ovl_cleanup(struct ovl_fs *ofs, struct inode *dir, struct dentry *dentry);
|
|
struct dentry *ovl_lookup_temp(struct ovl_fs *ofs, struct dentry *workdir);
|
|
struct dentry *ovl_create_temp(struct ovl_fs *ofs, struct dentry *workdir,
|
|
struct ovl_cattr *attr);
|
|
|
|
/* file.c */
|
|
extern const struct file_operations ovl_file_operations;
|
|
int __init ovl_aio_request_cache_init(void);
|
|
void ovl_aio_request_cache_destroy(void);
|
|
int ovl_real_fileattr_get(const struct path *realpath, struct fileattr *fa);
|
|
int ovl_real_fileattr_set(const struct path *realpath, struct fileattr *fa);
|
|
int ovl_fileattr_get(struct dentry *dentry, struct fileattr *fa);
|
|
int ovl_fileattr_set(struct mnt_idmap *idmap,
|
|
struct dentry *dentry, struct fileattr *fa);
|
|
|
|
/* copy_up.c */
|
|
int ovl_copy_up(struct dentry *dentry);
|
|
int ovl_copy_up_with_data(struct dentry *dentry);
|
|
int ovl_maybe_copy_up(struct dentry *dentry, int flags);
|
|
int ovl_copy_xattr(struct super_block *sb, const struct path *path, struct dentry *new);
|
|
int ovl_set_attr(struct ovl_fs *ofs, struct dentry *upper, struct kstat *stat);
|
|
struct ovl_fh *ovl_encode_real_fh(struct ovl_fs *ofs, struct dentry *real,
|
|
bool is_upper);
|
|
int ovl_set_origin(struct ovl_fs *ofs, struct dentry *lower,
|
|
struct dentry *upper);
|
|
|
|
/* export.c */
|
|
extern const struct export_operations ovl_export_operations;
|
|
|
|
/* super.c */
|
|
int ovl_fill_super(struct super_block *sb, struct fs_context *fc);
|
|
|
|
/* Will this overlay be forced to mount/remount ro? */
|
|
static inline bool ovl_force_readonly(struct ovl_fs *ofs)
|
|
{
|
|
return (!ovl_upper_mnt(ofs) || !ofs->workdir);
|
|
}
|