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Message-ID: <CAH2r5mt2SZPD+THkj12qxoZ9=F-NC_ZuhdoJRy0pQe5S+bUo3w@mail.gmail.com>
Date: Tue, 24 Nov 2015 11:34:52 -0600
From: Steve French <smfrench@...il.com>
To: unlisted-recipients:; (no To-header on input)
Cc: linux-afs@...r.kernel.org,
"linux-nfs@...r.kernel.org" <linux-nfs@...r.kernel.org>,
"linux-cifs@...r.kernel.org" <linux-cifs@...r.kernel.org>,
samba-technical <samba-technical@...ts.samba.org>,
LKML <linux-kernel@...r.kernel.org>,
linux-fsdevel <linux-fsdevel@...r.kernel.org>,
"linux-ext4@...r.kernel.org" <linux-ext4@...r.kernel.org>
Subject: Re: [PATCH 07/12] statx: CIFS: Return enhanced attributes
Is it worth storing the same creation time twice (in slightly
different formats, struct timespec and u64 DCE time) in cifsInodeInfo?
On Fri, Nov 20, 2015 at 8:55 AM, David Howells <dhowells@...hat.com> wrote:
> Return enhanced attributes from the CIFS filesystem. This includes the
> following:
>
> (1) Return the file creation time as btime. We assume that the creation
> time won't change over the life of the inode.
>
> (2) Set STATX_INFO_AUTOMOUNT on referral/submount directories.
>
> (3) Unset STATX_INO if we made up the inode number and didn't get it from
> the server.
>
> (4) Unset STATX_[UG]ID if we are either returning values passed to mount
> and/or the server doesn't return them.
>
> (5) Set STATX_IOC_FLAGS and map various Windows file attributes to
> FS_xxx_FL flags in st_ioc_flags, fetching them from the server if we
> don't have them yet or don't have a current copy. This includes the
> following:
>
> ATTR_READONLY -> FS_IMMUTABLE_FL
> ATTR_COMPRESSED -> FS_COMPR_FL
> ATTR_HIDDEN -> FS_HIDDEN_FL
> ATTR_SYSTEM -> FS_SYSTEM_FL
> ATTR_ARCHIVE -> FS_ARCHIVE_FL
>
> (6) Set certain STATX_INFO_xxx to reflect other Windows file attributes:
>
> ATTR_TEMPORARY -> STATX_INFO_TEMPORARY;
> ATTR_REPARSE -> STATX_INFO_REPARSE_POINT;
> ATTR_OFFLINE -> STATX_INFO_OFFLINE;
> ATTR_ENCRYPTED -> STATX_INFO_ENCRYPTED;
>
> (7) Set STATX_INFO_REMOTE on all files fetched by CIFS.
>
> (8) Set STATX_INFO_NONSYSTEM_OWNERSHIP on all files as they all have
> Windows ownership details too.
>
> Furthermore, what cifs_getattr() does can be controlled as follows:
>
> (1) If AT_NO_ATTR_SYNC is indicated then this will suppress the flushing
> of outstanding writes and the rereading of the inode's attributes with
> the server as detailed below.
>
> (2) Otherwise:
>
> (a) If AT_FORCE_ATTR_SYNC is indicated, or mtime, ctime or size are
> requested then the outstanding writes will be written to the
> server first.
>
> (b) The inode's attributes will be reread from the server:
>
> (i) if AT_FORCE_ATTR_SYNC is indicated;
>
> (ii) if the cached attributes have expired;
>
> (iii) extra attributes are requested that aren't normally stored.
>
> If the inode isn't synchronised, then the cached attributes will be used -
> even if expired - without reference to the server. Some attributes may be
> unavailable that would otherwise be provided.
>
> Note that cifs_revalidate_dentry() will issue an extra operation to get the
> FILE_ALL_INFO in addition to the FILE_UNIX_BASIC_INFO if it needs to
> collect creation time and attributes on behalf of cifs_getattr().
>
> [NOTE: THIS PATCH IS UNTESTED!]
>
> Signed-off-by: David Howells <dhowells@...hat.com>
> ---
>
> fs/cifs/cifsfs.h | 4 +-
> fs/cifs/cifsglob.h | 8 +++
> fs/cifs/dir.c | 2 -
> fs/cifs/inode.c | 124 +++++++++++++++++++++++++++++++++++++++++-----------
> 4 files changed, 108 insertions(+), 30 deletions(-)
>
> diff --git a/fs/cifs/cifsfs.h b/fs/cifs/cifsfs.h
> index c3cc1609025f..fb38d47d84de 100644
> --- a/fs/cifs/cifsfs.h
> +++ b/fs/cifs/cifsfs.h
> @@ -71,9 +71,9 @@ extern int cifs_rmdir(struct inode *, struct dentry *);
> extern int cifs_rename2(struct inode *, struct dentry *, struct inode *,
> struct dentry *, unsigned int);
> extern int cifs_revalidate_file_attr(struct file *filp);
> -extern int cifs_revalidate_dentry_attr(struct dentry *);
> +extern int cifs_revalidate_dentry_attr(struct dentry *, bool, bool);
> extern int cifs_revalidate_file(struct file *filp);
> -extern int cifs_revalidate_dentry(struct dentry *);
> +extern int cifs_revalidate_dentry(struct dentry *, bool, bool);
> extern int cifs_invalidate_mapping(struct inode *inode);
> extern int cifs_revalidate_mapping(struct inode *inode);
> extern int cifs_zap_mapping(struct inode *inode);
> diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
> index b406a32deb1f..493e40a15b86 100644
> --- a/fs/cifs/cifsglob.h
> +++ b/fs/cifs/cifsglob.h
> @@ -1152,7 +1152,11 @@ struct cifsInodeInfo {
> unsigned long flags;
> spinlock_t writers_lock;
> unsigned int writers; /* Number of writers on this inode */
> + bool btime_valid:1; /* stored creation time is valid */
> + bool uid_faked:1; /* true if i_uid is faked */
> + bool gid_faked:1; /* true if i_gid is faked */
> unsigned long time; /* jiffies of last update of inode */
> + struct timespec btime; /* creation time */
> u64 server_eof; /* current file size on server -- protected by i_lock */
> u64 uniqueid; /* server inode number */
> u64 createtime; /* creation time on server */
> @@ -1365,6 +1369,9 @@ struct dfs_info3_param {
> #define CIFS_FATTR_NEED_REVAL 0x4
> #define CIFS_FATTR_INO_COLLISION 0x8
> #define CIFS_FATTR_UNKNOWN_NLINK 0x10
> +#define CIFS_FATTR_WINATTRS_VALID 0x20 /* T if cf_btime and cf_cifsattrs valid */
> +#define CIFS_FATTR_UID_FAKED 0x40 /* T if cf_uid is faked */
> +#define CIFS_FATTR_GID_FAKED 0x80 /* T if cf_gid is faked */
>
> struct cifs_fattr {
> u32 cf_flags;
> @@ -1382,6 +1389,7 @@ struct cifs_fattr {
> struct timespec cf_atime;
> struct timespec cf_mtime;
> struct timespec cf_ctime;
> + struct timespec cf_btime;
> };
>
> static inline void free_dfs_info_param(struct dfs_info3_param *param)
> diff --git a/fs/cifs/dir.c b/fs/cifs/dir.c
> index c3eb998a99bd..4984f04b0677 100644
> --- a/fs/cifs/dir.c
> +++ b/fs/cifs/dir.c
> @@ -792,7 +792,7 @@ cifs_d_revalidate(struct dentry *direntry, unsigned int flags)
> return -ECHILD;
>
> if (d_really_is_positive(direntry)) {
> - if (cifs_revalidate_dentry(direntry))
> + if (cifs_revalidate_dentry(direntry, false, false))
> return 0;
> else {
> /*
> diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
> index 6b66dd5d1540..fcb024efbd4b 100644
> --- a/fs/cifs/inode.c
> +++ b/fs/cifs/inode.c
> @@ -166,13 +166,21 @@ cifs_fattr_to_inode(struct inode *inode, struct cifs_fattr *fattr)
> cifs_nlink_fattr_to_inode(inode, fattr);
> inode->i_uid = fattr->cf_uid;
> inode->i_gid = fattr->cf_gid;
> + if (fattr->cf_flags & CIFS_FATTR_UID_FAKED)
> + cifs_i->uid_faked = true;
> + if (fattr->cf_flags & CIFS_FATTR_GID_FAKED)
> + cifs_i->gid_faked = true;
>
> /* if dynperm is set, don't clobber existing mode */
> if (inode->i_state & I_NEW ||
> !(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DYNPERM))
> inode->i_mode = fattr->cf_mode;
>
> - cifs_i->cifsAttrs = fattr->cf_cifsattrs;
> + if (fattr->cf_flags & CIFS_FATTR_WINATTRS_VALID) {
> + cifs_i->cifsAttrs = fattr->cf_cifsattrs;
> + cifs_i->btime = fattr->cf_btime;
> + cifs_i->btime_valid = true;
> + }
>
> if (fattr->cf_flags & CIFS_FATTR_NEED_REVAL)
> cifs_i->time = 0;
> @@ -284,18 +292,22 @@ cifs_unix_basic_to_fattr(struct cifs_fattr *fattr, FILE_UNIX_BASIC_INFO *info,
> u64 id = le64_to_cpu(info->Uid);
> if (id < ((uid_t)-1)) {
> kuid_t uid = make_kuid(&init_user_ns, id);
> - if (uid_valid(uid))
> + if (uid_valid(uid)) {
> fattr->cf_uid = uid;
> + fattr->cf_flags |= CIFS_FATTR_UID_FAKED;
> + }
> }
> }
> -
> +
> fattr->cf_gid = cifs_sb->mnt_gid;
> if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_OVERR_GID)) {
> u64 id = le64_to_cpu(info->Gid);
> if (id < ((gid_t)-1)) {
> kgid_t gid = make_kgid(&init_user_ns, id);
> - if (gid_valid(gid))
> + if (gid_valid(gid)) {
> fattr->cf_gid = gid;
> + fattr->cf_flags |= CIFS_FATTR_GID_FAKED;
> + }
> }
> }
>
> @@ -324,7 +336,8 @@ cifs_create_dfs_fattr(struct cifs_fattr *fattr, struct super_block *sb)
> fattr->cf_ctime = CURRENT_TIME;
> fattr->cf_mtime = CURRENT_TIME;
> fattr->cf_nlink = 2;
> - fattr->cf_flags |= CIFS_FATTR_DFS_REFERRAL;
> + fattr->cf_flags |= CIFS_FATTR_DFS_REFERRAL |
> + CIFS_FATTR_UID_FAKED | CIFS_FATTR_GID_FAKED;
> }
>
> static int
> @@ -590,6 +603,7 @@ cifs_all_info_to_fattr(struct cifs_fattr *fattr, FILE_ALL_INFO *info,
> struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
>
> memset(fattr, 0, sizeof(*fattr));
> + fattr->cf_flags = CIFS_FATTR_WINATTRS_VALID;
> fattr->cf_cifsattrs = le32_to_cpu(info->Attributes);
> if (info->DeletePending)
> fattr->cf_flags |= CIFS_FATTR_DELETE_PENDING;
> @@ -601,6 +615,7 @@ cifs_all_info_to_fattr(struct cifs_fattr *fattr, FILE_ALL_INFO *info,
>
> fattr->cf_ctime = cifs_NTtimeToUnix(info->ChangeTime);
> fattr->cf_mtime = cifs_NTtimeToUnix(info->LastWriteTime);
> + fattr->cf_btime = cifs_NTtimeToUnix(info->CreationTime);
>
> if (adjust_tz) {
> fattr->cf_ctime.tv_sec += tcon->ses->server->timeAdj;
> @@ -1887,7 +1902,8 @@ int cifs_revalidate_file_attr(struct file *filp)
> return rc;
> }
>
> -int cifs_revalidate_dentry_attr(struct dentry *dentry)
> +int cifs_revalidate_dentry_attr(struct dentry *dentry,
> + bool want_extra_bits, bool force)
> {
> unsigned int xid;
> int rc = 0;
> @@ -1898,7 +1914,7 @@ int cifs_revalidate_dentry_attr(struct dentry *dentry)
> if (inode == NULL)
> return -ENOENT;
>
> - if (!cifs_inode_needs_reval(inode))
> + if (!force && !cifs_inode_needs_reval(inode))
> return rc;
>
> xid = get_xid();
> @@ -1915,9 +1931,12 @@ int cifs_revalidate_dentry_attr(struct dentry *dentry)
> full_path, inode, inode->i_count.counter,
> dentry, dentry->d_time, jiffies);
>
> - if (cifs_sb_master_tcon(CIFS_SB(sb))->unix_ext)
> + if (cifs_sb_master_tcon(CIFS_SB(sb))->unix_ext) {
> rc = cifs_get_inode_info_unix(&inode, full_path, sb, xid);
> - else
> + if (rc != 0)
> + goto out;
> + }
> + if (!cifs_sb_master_tcon(CIFS_SB(sb))->unix_ext || want_extra_bits)
> rc = cifs_get_inode_info(&inode, full_path, NULL, sb,
> xid, NULL);
>
> @@ -1940,12 +1959,13 @@ int cifs_revalidate_file(struct file *filp)
> }
>
> /* revalidate a dentry's inode attributes */
> -int cifs_revalidate_dentry(struct dentry *dentry)
> +int cifs_revalidate_dentry(struct dentry *dentry,
> + bool want_extra_bits, bool force)
> {
> int rc;
> struct inode *inode = d_inode(dentry);
>
> - rc = cifs_revalidate_dentry_attr(dentry);
> + rc = cifs_revalidate_dentry_attr(dentry, want_extra_bits, force);
> if (rc)
> return rc;
>
> @@ -1958,28 +1978,62 @@ int cifs_getattr(struct vfsmount *mnt, struct dentry *dentry,
> struct cifs_sb_info *cifs_sb = CIFS_SB(dentry->d_sb);
> struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
> struct inode *inode = d_inode(dentry);
> + struct cifsInodeInfo *cifs_i = CIFS_I(inode);
> + bool force = stat->query_flags & AT_FORCE_ATTR_SYNC;
> + bool want_extra_bits = false;
> + u32 info, ioc = 0;
> + u32 attrs;
> int rc;
>
> - /*
> - * We need to be sure that all dirty pages are written and the server
> - * has actual ctime, mtime and file length.
> - */
> - if (!CIFS_CACHE_READ(CIFS_I(inode)) && inode->i_mapping &&
> - inode->i_mapping->nrpages != 0) {
> - rc = filemap_fdatawait(inode->i_mapping);
> - if (rc) {
> - mapping_set_error(inode->i_mapping, rc);
> - return rc;
> + if (cifs_i->uid_faked)
> + stat->request_mask &= ~STATX_UID;
> + if (cifs_i->gid_faked)
> + stat->request_mask &= ~STATX_GID;
> +
> + if ((stat->request_mask & STATX_BTIME && !cifs_i->btime_valid) ||
> + stat->request_mask & STATX_IOC_FLAGS)
> + want_extra_bits = force = true;
> +
> + if (!(stat->query_flags & AT_NO_ATTR_SYNC)) {
> + /* Unless we're explicitly told not to sync, we need to be sure
> + * that all dirty pages are written and the server has actual
> + * ctime, mtime and file length.
> + */
> + bool flush = force;
> +
> + if (stat->request_mask &
> + (STATX_CTIME | STATX_MTIME | STATX_SIZE))
> + flush = true;
> +
> + if (flush &&
> + !CIFS_CACHE_READ(CIFS_I(inode)) && inode->i_mapping &&
> + inode->i_mapping->nrpages != 0) {
> + rc = filemap_fdatawait(inode->i_mapping);
> + if (rc) {
> + mapping_set_error(inode->i_mapping, rc);
> + return rc;
> + }
> }
> - }
>
> - rc = cifs_revalidate_dentry_attr(dentry);
> - if (rc)
> - return rc;
> + rc = cifs_revalidate_dentry(dentry, want_extra_bits, force);
> + if (rc)
> + return rc;
> + }
>
> generic_fillattr(inode, stat);
> stat->blksize = CIFS_MAX_MSGSIZE;
> - stat->ino = CIFS_I(inode)->uniqueid;
> +
> + info = STATX_INFO_REMOTE | STATX_INFO_NONSYSTEM_OWNERSHIP;
> +
> + if (cifs_i->btime_valid) {
> + stat->btime = cifs_i->btime;
> + stat->result_mask |= STATX_BTIME;
> + }
> +
> + /* We don't promise an inode number if we made one up */
> + stat->ino = cifs_i->uniqueid;
> + if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM))
> + stat->result_mask &= ~STATX_INO;
>
> /*
> * If on a multiuser mount without unix extensions or cifsacl being
> @@ -1993,8 +2047,24 @@ int cifs_getattr(struct vfsmount *mnt, struct dentry *dentry,
> stat->uid = current_fsuid();
> if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_OVERR_GID))
> stat->gid = current_fsgid();
> + stat->result_mask &= ~(STATX_UID | STATX_GID);
> }
> - return rc;
> +
> + attrs = cifs_i->cifsAttrs;
> + if (attrs & ATTR_TEMPORARY) info |= STATX_INFO_TEMPORARY;
> + if (attrs & ATTR_REPARSE) info |= STATX_INFO_REPARSE_POINT;
> + if (attrs & ATTR_OFFLINE) info |= STATX_INFO_OFFLINE;
> + if (attrs & ATTR_ENCRYPTED) info |= STATX_INFO_ENCRYPTED;
> + stat->information |= info;
> +
> + if (attrs & ATTR_READONLY) ioc |= FS_IMMUTABLE_FL;
> + if (attrs & ATTR_COMPRESSED) ioc |= FS_COMPR_FL;
> + if (attrs & ATTR_HIDDEN) ioc |= FS_HIDDEN_FL;
> + if (attrs & ATTR_SYSTEM) ioc |= FS_SYSTEM_FL;
> + if (attrs & ATTR_ARCHIVE) ioc |= FS_ARCHIVE_FL;
> + stat->ioc_flags |= ioc;
> +
> + return 0;
> }
>
> static int cifs_truncate_page(struct address_space *mapping, loff_t from)
>
> --
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--
Thanks,
Steve
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