diff options
Diffstat (limited to 'fs/9p/fid.c')
-rw-r--r-- | fs/9p/fid.c | 124 |
1 files changed, 92 insertions, 32 deletions
diff --git a/fs/9p/fid.c b/fs/9p/fid.c index 3d681a2c2731..23cf9b2fbfe4 100644 --- a/fs/9p/fid.c +++ b/fs/9p/fid.c @@ -19,26 +19,76 @@ #include "v9fs_vfs.h" #include "fid.h" +static inline void __add_fid(struct dentry *dentry, struct p9_fid *fid) +{ + hlist_add_head(&fid->dlist, (struct hlist_head *)&dentry->d_fsdata); +} + + /** * v9fs_fid_add - add a fid to a dentry * @dentry: dentry that the fid is being added to - * @fid: fid to add + * @pfid: fid to add, NULLed out * */ - -static inline void __add_fid(struct dentry *dentry, struct p9_fid *fid) +void v9fs_fid_add(struct dentry *dentry, struct p9_fid **pfid) { - hlist_add_head(&fid->dlist, (struct hlist_head *)&dentry->d_fsdata); -} + struct p9_fid *fid = *pfid; -void v9fs_fid_add(struct dentry *dentry, struct p9_fid *fid) -{ spin_lock(&dentry->d_lock); __add_fid(dentry, fid); spin_unlock(&dentry->d_lock); + + *pfid = NULL; +} + +/** + * v9fs_fid_find_inode - search for an open fid off of the inode list + * @inode: return a fid pointing to a specific inode + * @uid: return a fid belonging to the specified user + * + */ + +static struct p9_fid *v9fs_fid_find_inode(struct inode *inode, kuid_t uid) +{ + struct hlist_head *h; + struct p9_fid *fid, *ret = NULL; + + p9_debug(P9_DEBUG_VFS, " inode: %p\n", inode); + + spin_lock(&inode->i_lock); + h = (struct hlist_head *)&inode->i_private; + hlist_for_each_entry(fid, h, ilist) { + if (uid_eq(fid->uid, uid)) { + p9_fid_get(fid); + ret = fid; + break; + } + } + spin_unlock(&inode->i_lock); + return ret; } /** + * v9fs_open_fid_add - add an open fid to an inode + * @inode: inode that the fid is being added to + * @pfid: fid to add, NULLed out + * + */ + +void v9fs_open_fid_add(struct inode *inode, struct p9_fid **pfid) +{ + struct p9_fid *fid = *pfid; + + spin_lock(&inode->i_lock); + hlist_add_head(&fid->ilist, (struct hlist_head *)&inode->i_private); + spin_unlock(&inode->i_lock); + + *pfid = NULL; +} + + +/** * v9fs_fid_find - retrieve a fid that belongs to the specified uid * @dentry: dentry to look for fid in * @uid: return fid that belongs to the specified user @@ -57,14 +107,19 @@ static struct p9_fid *v9fs_fid_find(struct dentry *dentry, kuid_t uid, int any) /* we'll recheck under lock if there's anything to look in */ if (dentry->d_fsdata) { struct hlist_head *h = (struct hlist_head *)&dentry->d_fsdata; + spin_lock(&dentry->d_lock); hlist_for_each_entry(fid, h, dlist) { if (any || uid_eq(fid->uid, uid)) { ret = fid; + p9_fid_get(ret); break; } } spin_unlock(&dentry->d_lock); + } else { + if (dentry->d_inode) + ret = v9fs_fid_find_inode(dentry->d_inode, uid); } return ret; @@ -103,9 +158,9 @@ static struct p9_fid *v9fs_fid_lookup_with_uid(struct dentry *dentry, { struct dentry *ds; const unsigned char **wnames, *uname; - int i, n, l, clone, access; + int i, n, l, access; struct v9fs_session_info *v9ses; - struct p9_fid *fid, *old_fid = NULL; + struct p9_fid *fid, *root_fid, *old_fid; v9ses = v9fs_dentry2v9ses(dentry); access = v9ses->flags & V9FS_ACCESS_MASK; @@ -122,20 +177,23 @@ static struct p9_fid *v9fs_fid_lookup_with_uid(struct dentry *dentry, fid = v9fs_fid_find(ds, uid, any); if (fid) { /* Found the parent fid do a lookup with that */ - fid = p9_client_walk(fid, 1, &dentry->d_name.name, 1); + old_fid = fid; + + fid = p9_client_walk(old_fid, 1, &dentry->d_name.name, 1); + p9_fid_put(old_fid); goto fid_out; } up_read(&v9ses->rename_sem); /* start from the root and try to do a lookup */ - fid = v9fs_fid_find(dentry->d_sb->s_root, uid, any); - if (!fid) { + root_fid = v9fs_fid_find(dentry->d_sb->s_root, uid, any); + if (!root_fid) { /* the user is not attached to the fs yet */ if (access == V9FS_ACCESS_SINGLE) return ERR_PTR(-EPERM); if (v9fs_proto_dotu(v9ses) || v9fs_proto_dotl(v9ses)) - uname = NULL; + uname = NULL; else uname = v9ses->uname; @@ -144,11 +202,13 @@ static struct p9_fid *v9fs_fid_lookup_with_uid(struct dentry *dentry, if (IS_ERR(fid)) return fid; - v9fs_fid_add(dentry->d_sb->s_root, fid); + root_fid = p9_fid_get(fid); + v9fs_fid_add(dentry->d_sb->s_root, &fid); } /* If we are root ourself just return that */ if (dentry->d_sb->s_root == dentry) - return fid; + return root_fid; + /* * Do a multipath walk with attached root. * When walking parent we need to make sure we @@ -160,30 +220,27 @@ static struct p9_fid *v9fs_fid_lookup_with_uid(struct dentry *dentry, fid = ERR_PTR(n); goto err_out; } - clone = 1; + fid = root_fid; + old_fid = root_fid; i = 0; while (i < n) { l = min(n - i, P9_MAXWELEM); /* * We need to hold rename lock when doing a multipath - * walk to ensure none of the patch component change + * walk to ensure none of the path components change */ - fid = p9_client_walk(fid, l, &wnames[i], clone); + fid = p9_client_walk(old_fid, l, &wnames[i], + old_fid == root_fid /* clone */); + /* non-cloning walk will return the same fid */ + if (fid != old_fid) { + p9_fid_put(old_fid); + old_fid = fid; + } if (IS_ERR(fid)) { - if (old_fid) { - /* - * If we fail, clunk fid which are mapping - * to path component and not the last component - * of the path. - */ - p9_client_clunk(old_fid); - } kfree(wnames); goto err_out; } - old_fid = fid; i += l; - clone = 0; } kfree(wnames); fid_out: @@ -191,10 +248,11 @@ fid_out: spin_lock(&dentry->d_lock); if (d_unhashed(dentry)) { spin_unlock(&dentry->d_lock); - p9_client_clunk(fid); + p9_fid_put(fid); fid = ERR_PTR(-ENOENT); } else { __add_fid(dentry, fid); + p9_fid_get(fid); spin_unlock(&dentry->d_lock); } } @@ -245,11 +303,13 @@ struct p9_fid *v9fs_fid_lookup(struct dentry *dentry) struct p9_fid *v9fs_writeback_fid(struct dentry *dentry) { int err; - struct p9_fid *fid; + struct p9_fid *fid, *ofid; - fid = clone_fid(v9fs_fid_lookup_with_uid(dentry, GLOBAL_ROOT_UID, 0)); + ofid = v9fs_fid_lookup_with_uid(dentry, GLOBAL_ROOT_UID, 0); + fid = clone_fid(ofid); if (IS_ERR(fid)) goto error_out; + p9_fid_put(ofid); /* * writeback fid will only be used to write back the * dirty pages. We always request for the open fid in read-write @@ -258,7 +318,7 @@ struct p9_fid *v9fs_writeback_fid(struct dentry *dentry) */ err = p9_client_open(fid, O_RDWR); if (err < 0) { - p9_client_clunk(fid); + p9_fid_put(fid); fid = ERR_PTR(err); goto error_out; } |