| Message ID | 1350739560-9197-1-git-send-email-shirishpargaonkar@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Sat, 20 Oct 2012 08:26:00 -0500 shirishpargaonkar@gmail.com wrote: > From: Shirish Pargaonkar <shirishpargaonkar@gmail.com> > > > Add support of Alternate Data Streams (ads). > > The generic access flags that cifs client currently employs are sufficient > for alternate data streams as well (MS-CIFS 2.2.4.64.1). > > The stream file and stream type are specified using : after the file name, > so that is used to differentiate between a regular file and its > alternate data streams and stream types. > Since they all have the same file id, each path name, > file name:stream name:stream type, has a separate inode with that same > file id but a distinct private data (path name) in that inode to > distinguish them. > > This scheme applies only to non-posix compliant servers such as Windows. > > One operation that does not work is Rename (0x7). > > > Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com> > --- > fs/cifs/cifsfs.c | 1 + > fs/cifs/cifsglob.h | 2 ++ > fs/cifs/inode.c | 34 +++++++++++++++++++++++++++++++++- > 3 files changed, 36 insertions(+), 1 deletions(-) > > diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c > index a41044a..1a02c81 100644 > --- a/fs/cifs/cifsfs.c > +++ b/fs/cifs/cifsfs.c > @@ -264,6 +264,7 @@ cifs_evict_inode(struct inode *inode) > { > truncate_inode_pages(&inode->i_data, 0); > clear_inode(inode); > + kfree(inode->i_private); Are you sure that i_private is always initialized to NULL? Hmm...looks like they probably are in inode_init_always. Ok... > cifs_fscache_release_inode_cookie(inode); > } > > diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h > index f5af252..26d65c7 100644 > --- a/fs/cifs/cifsglob.h > +++ b/fs/cifs/cifsglob.h > @@ -1251,6 +1251,7 @@ struct dfs_info3_param { > #define CIFS_FATTR_DELETE_PENDING 0x2 > #define CIFS_FATTR_NEED_REVAL 0x4 > #define CIFS_FATTR_INO_COLLISION 0x8 > +#define CIFS_FATTR_ALTDATASTR 0x10 > > struct cifs_fattr { > u32 cf_flags; > @@ -1268,6 +1269,7 @@ struct cifs_fattr { > struct timespec cf_atime; > struct timespec cf_mtime; > struct timespec cf_ctime; > + char *cf_private; > }; > > static inline void free_dfs_info_param(struct dfs_info3_param *param) > diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c > index afdff79..201ec46 100644 > --- a/fs/cifs/inode.c > +++ b/fs/cifs/inode.c > @@ -615,10 +615,12 @@ cifs_get_inode_info(struct inode **inode, const char *full_path, > struct tcon_link *tlink; > struct cifs_sb_info *cifs_sb = CIFS_SB(sb); > char *buf = NULL; > + char *altstr = NULL; > bool adjust_tz = false; > struct cifs_fattr fattr; > struct cifs_search_info *srchinf = NULL; > > + fattr.cf_private = NULL; > tlink = cifs_sb_tlink(cifs_sb); > if (IS_ERR(tlink)) > return PTR_ERR(tlink); > @@ -746,14 +748,34 @@ cifs_get_inode_info(struct inode **inode, const char *full_path, > } > > if (!*inode) { > + altstr = strchr(full_path, ':'); > + if (altstr) { > + fattr.cf_private = kstrdup(altstr, GFP_KERNEL); > + if (!fattr.cf_private) { > + rc = -ENOMEM; > + goto cgii_exit; > + } > + fattr.cf_flags |= CIFS_FATTR_ALTDATASTR; > + } > + > *inode = cifs_iget(sb, &fattr); > - if (!*inode) > + if (*inode) { > + if (altstr && !((*inode)->i_flags & S_PRIVATE)) { > + (*inode)->i_private = > + kstrdup(altstr, GFP_KERNEL); > + if ((*inode)->i_private) > + (*inode)->i_flags |= S_PRIVATE; > + else > + rc = -ENOMEM; > + } > + } else ^^^^^ Why redo the allocation and copy here? You could just hand off the one you just allocated... > rc = -ENOMEM; > } else { > cifs_fattr_to_inode(*inode, &fattr); > } > > cgii_exit: > + kfree(fattr.cf_private); > kfree(buf); > cifs_put_tlink(tlink); > return rc; > @@ -784,6 +806,16 @@ cifs_find_inode(struct inode *inode, void *opaque) > if (S_ISDIR(inode->i_mode) && !hlist_empty(&inode->i_dentry)) > fattr->cf_flags |= CIFS_FATTR_INO_COLLISION; > > + /* looking for an inode of a alternate data stream (full pathname) */ > + if (fattr->cf_flags & CIFS_FATTR_ALTDATASTR) { > + if (!(inode->i_flags & S_PRIVATE)) { > + return 0; > + } else { > + if (strcmp(inode->i_private, fattr->cf_private)) > + return 0; > + } > + } > + > return 1; > } > Looks like S_PRIVATE has some other security/permissions related effects. Do you expect any behavior change from using it here?
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c index a41044a..1a02c81 100644 --- a/fs/cifs/cifsfs.c +++ b/fs/cifs/cifsfs.c @@ -264,6 +264,7 @@ cifs_evict_inode(struct inode *inode) { truncate_inode_pages(&inode->i_data, 0); clear_inode(inode); + kfree(inode->i_private); cifs_fscache_release_inode_cookie(inode); } diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h index f5af252..26d65c7 100644 --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -1251,6 +1251,7 @@ struct dfs_info3_param { #define CIFS_FATTR_DELETE_PENDING 0x2 #define CIFS_FATTR_NEED_REVAL 0x4 #define CIFS_FATTR_INO_COLLISION 0x8 +#define CIFS_FATTR_ALTDATASTR 0x10 struct cifs_fattr { u32 cf_flags; @@ -1268,6 +1269,7 @@ struct cifs_fattr { struct timespec cf_atime; struct timespec cf_mtime; struct timespec cf_ctime; + char *cf_private; }; static inline void free_dfs_info_param(struct dfs_info3_param *param) diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c index afdff79..201ec46 100644 --- a/fs/cifs/inode.c +++ b/fs/cifs/inode.c @@ -615,10 +615,12 @@ cifs_get_inode_info(struct inode **inode, const char *full_path, struct tcon_link *tlink; struct cifs_sb_info *cifs_sb = CIFS_SB(sb); char *buf = NULL; + char *altstr = NULL; bool adjust_tz = false; struct cifs_fattr fattr; struct cifs_search_info *srchinf = NULL; + fattr.cf_private = NULL; tlink = cifs_sb_tlink(cifs_sb); if (IS_ERR(tlink)) return PTR_ERR(tlink); @@ -746,14 +748,34 @@ cifs_get_inode_info(struct inode **inode, const char *full_path, } if (!*inode) { + altstr = strchr(full_path, ':'); + if (altstr) { + fattr.cf_private = kstrdup(altstr, GFP_KERNEL); + if (!fattr.cf_private) { + rc = -ENOMEM; + goto cgii_exit; + } + fattr.cf_flags |= CIFS_FATTR_ALTDATASTR; + } + *inode = cifs_iget(sb, &fattr); - if (!*inode) + if (*inode) { + if (altstr && !((*inode)->i_flags & S_PRIVATE)) { + (*inode)->i_private = + kstrdup(altstr, GFP_KERNEL); + if ((*inode)->i_private) + (*inode)->i_flags |= S_PRIVATE; + else + rc = -ENOMEM; + } + } else rc = -ENOMEM; } else { cifs_fattr_to_inode(*inode, &fattr); } cgii_exit: + kfree(fattr.cf_private); kfree(buf); cifs_put_tlink(tlink); return rc; @@ -784,6 +806,16 @@ cifs_find_inode(struct inode *inode, void *opaque) if (S_ISDIR(inode->i_mode) && !hlist_empty(&inode->i_dentry)) fattr->cf_flags |= CIFS_FATTR_INO_COLLISION; + /* looking for an inode of a alternate data stream (full pathname) */ + if (fattr->cf_flags & CIFS_FATTR_ALTDATASTR) { + if (!(inode->i_flags & S_PRIVATE)) { + return 0; + } else { + if (strcmp(inode->i_private, fattr->cf_private)) + return 0; + } + } + return 1; }