diff options
author | Latchesar Ionkov <lucho@ionkov.net> | 2006-03-02 02:54:30 -0800 |
---|---|---|
committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-03-02 08:33:07 -0800 |
commit | 6a3124a3946c16159c3faf83e62ffdb5d1134b3a (patch) | |
tree | 989f1e89ed0971824db973af5347b879e12c67cd /fs/9p/vfs_inode.c | |
parent | 77a3313551afd53c90012e5a87f7f2b2195fc67e (diff) | |
download | kernel_samsung_smdk4412-6a3124a3946c16159c3faf83e62ffdb5d1134b3a.zip kernel_samsung_smdk4412-6a3124a3946c16159c3faf83e62ffdb5d1134b3a.tar.gz kernel_samsung_smdk4412-6a3124a3946c16159c3faf83e62ffdb5d1134b3a.tar.bz2 |
[PATCH] v9fs: fix atomic create open
In order to assure atomic create+open v9fs stores the open fid produced by
v9fs_vfs_create in the dentry, from where v9fs_file_open retrieves it and
associates it with the open file.
This patch modifies v9fs to use nameidata.intent.open values to do the atomic
create+open.
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'fs/9p/vfs_inode.c')
-rw-r--r-- | fs/9p/vfs_inode.c | 478 |
1 files changed, 312 insertions, 166 deletions
diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c index 63e5b03..dce729d 100644 --- a/fs/9p/vfs_inode.c +++ b/fs/9p/vfs_inode.c @@ -125,6 +125,38 @@ static int p9mode2unixmode(struct v9fs_session_info *v9ses, int mode) return res; } +int v9fs_uflags2omode(int uflags) +{ + int ret; + + ret = 0; + switch (uflags&3) { + default: + case O_RDONLY: + ret = V9FS_OREAD; + break; + + case O_WRONLY: + ret = V9FS_OWRITE; + break; + + case O_RDWR: + ret = V9FS_ORDWR; + break; + } + + if (uflags & O_EXCL) + ret |= V9FS_OEXCL; + + if (uflags & O_TRUNC) + ret |= V9FS_OTRUNC; + + if (uflags & O_APPEND) + ret |= V9FS_OAPPEND; + + return ret; +} + /** * v9fs_blank_wstat - helper function to setup a 9P stat structure * @v9ses: 9P session info (for determining extended mode) @@ -163,7 +195,7 @@ v9fs_blank_wstat(struct v9fs_wstat *wstat) struct inode *v9fs_get_inode(struct super_block *sb, int mode) { - struct inode *inode = NULL; + struct inode *inode; struct v9fs_session_info *v9ses = sb->s_fs_info; dprintk(DEBUG_VFS, "super block: %p mode: %o\n", sb, mode); @@ -222,171 +254,135 @@ struct inode *v9fs_get_inode(struct super_block *sb, int mode) return inode; } -/** - * v9fs_create - helper function to create files and directories - * @dir: directory inode file is being created in - * @file_dentry: dentry file is being created in - * @perm: permissions file is being created with - * @open_mode: resulting open mode for file - * - */ - static int -v9fs_create(struct inode *dir, - struct dentry *file_dentry, - unsigned int perm, unsigned int open_mode) +v9fs_create(struct v9fs_session_info *v9ses, u32 pfid, char *name, + u32 perm, u8 mode, u32 *fidp, struct v9fs_qid *qid, u32 *iounit) { - struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dir); - struct super_block *sb = dir->i_sb; - struct v9fs_fid *dirfid = - v9fs_fid_lookup(file_dentry->d_parent); - struct v9fs_fid *fid = NULL; - struct inode *file_inode = NULL; - struct v9fs_fcall *fcall = NULL; - struct v9fs_qid qid; - int dirfidnum = -1; - long newfid = -1; - int result = 0; - unsigned int iounit = 0; - int wfidno = -1; + u32 fid; int err; + struct v9fs_fcall *fcall; - perm = unixmode2p9mode(v9ses, perm); - - dprintk(DEBUG_VFS, "dir: %p dentry: %p perm: %o mode: %o\n", dir, - file_dentry, perm, open_mode); - - if (!dirfid) - return -EBADF; - - dirfidnum = dirfid->fid; - if (dirfidnum < 0) { - dprintk(DEBUG_ERROR, "No fid for the directory #%lu\n", - dir->i_ino); - return -EBADF; - } - - if (file_dentry->d_inode) { - dprintk(DEBUG_ERROR, - "Odd. There is an inode for dir %lu, name :%s:\n", - dir->i_ino, file_dentry->d_name.name); - return -EEXIST; - } - - newfid = v9fs_get_idpool(&v9ses->fidpool); - if (newfid < 0) { + fid = v9fs_get_idpool(&v9ses->fidpool); + if (fid < 0) { eprintk(KERN_WARNING, "no free fids available\n"); - return -ENOSPC; + err = -ENOSPC; + goto error; } - result = v9fs_t_walk(v9ses, dirfidnum, newfid, NULL, &fcall); - if (result < 0) { + err = v9fs_t_walk(v9ses, pfid, fid, NULL, &fcall); + if (err < 0) { PRINT_FCALL_ERROR("clone error", fcall); - v9fs_put_idpool(newfid, &v9ses->fidpool); - newfid = -1; - goto CleanUpFid; + goto error; } - kfree(fcall); - fcall = NULL; - result = v9fs_t_create(v9ses, newfid, (char *)file_dentry->d_name.name, - perm, open_mode, &fcall); - if (result < 0) { + err = v9fs_t_create(v9ses, fid, name, perm, mode, &fcall); + if (err < 0) { PRINT_FCALL_ERROR("create fails", fcall); - goto CleanUpFid; + goto error; } - iounit = fcall->params.rcreate.iounit; - qid = fcall->params.rcreate.qid; + if (iounit) + *iounit = fcall->params.rcreate.iounit; + + if (qid) + *qid = fcall->params.rcreate.qid; + + if (fidp) + *fidp = fid; + kfree(fcall); - fcall = NULL; + return 0; - if (!(perm&V9FS_DMDIR)) { - fid = v9fs_fid_create(file_dentry, v9ses, newfid, 1); - dprintk(DEBUG_VFS, "fid %p %d\n", fid, fid->fidcreate); - if (!fid) { - result = -ENOMEM; - goto CleanUpFid; - } +error: + if (fid >= 0) + v9fs_put_idpool(fid, &v9ses->fidpool); - fid->qid = qid; - fid->iounit = iounit; - } else { - err = v9fs_t_clunk(v9ses, newfid); - newfid = -1; - if (err < 0) - dprintk(DEBUG_ERROR, "clunk for mkdir failed: %d\n", err); - } + kfree(fcall); + return err; +} + +static struct v9fs_fid* +v9fs_clone_walk(struct v9fs_session_info *v9ses, u32 fid, struct dentry *dentry) +{ + int err; + u32 nfid; + struct v9fs_fid *ret; + struct v9fs_fcall *fcall; - /* walk to the newly created file and put the fid in the dentry */ - wfidno = v9fs_get_idpool(&v9ses->fidpool); - if (wfidno < 0) { + nfid = v9fs_get_idpool(&v9ses->fidpool); + if (nfid < 0) { eprintk(KERN_WARNING, "no free fids available\n"); - return -ENOSPC; + err = -ENOSPC; + goto error; } - result = v9fs_t_walk(v9ses, dirfidnum, wfidno, - (char *) file_dentry->d_name.name, &fcall); - if (result < 0) { - PRINT_FCALL_ERROR("clone error", fcall); - v9fs_put_idpool(wfidno, &v9ses->fidpool); - wfidno = -1; - goto CleanUpFid; + err = v9fs_t_walk(v9ses, fid, nfid, (char *) dentry->d_name.name, + &fcall); + + if (err < 0) { + PRINT_FCALL_ERROR("walk error", fcall); + v9fs_put_idpool(nfid, &v9ses->fidpool); + goto error; } + kfree(fcall); fcall = NULL; + ret = v9fs_fid_create(v9ses, nfid); + if (!ret) { + err = -ENOMEM; + goto clunk_fid; + } - if (!v9fs_fid_create(file_dentry, v9ses, wfidno, 0)) { - v9fs_put_idpool(wfidno, &v9ses->fidpool); - - goto CleanUpFid; + err = v9fs_fid_insert(ret, dentry); + if (err < 0) { + v9fs_fid_destroy(ret); + goto clunk_fid; } - if ((perm & V9FS_DMSYMLINK) || (perm & V9FS_DMLINK) || - (perm & V9FS_DMNAMEDPIPE) || (perm & V9FS_DMSOCKET) || - (perm & V9FS_DMDEVICE)) - return 0; + return ret; - result = v9fs_t_stat(v9ses, wfidno, &fcall); - if (result < 0) { - PRINT_FCALL_ERROR("stat error", fcall); - goto CleanUpFid; - } +clunk_fid: + v9fs_t_clunk(v9ses, nfid); + +error: + kfree(fcall); + return ERR_PTR(err); +} +struct inode * +v9fs_inode_from_fid(struct v9fs_session_info *v9ses, u32 fid, + struct super_block *sb) +{ + int err, umode; + struct inode *ret; + struct v9fs_fcall *fcall; - file_inode = v9fs_get_inode(sb, - p9mode2unixmode(v9ses, fcall->params.rstat.stat.mode)); + ret = NULL; + err = v9fs_t_stat(v9ses, fid, &fcall); + if (err) { + PRINT_FCALL_ERROR("stat error", fcall); + goto error; + } - if ((!file_inode) || IS_ERR(file_inode)) { - dprintk(DEBUG_ERROR, "create inode failed\n"); - result = -EBADF; - goto CleanUpFid; + umode = p9mode2unixmode(v9ses, fcall->params.rstat.stat.mode); + ret = v9fs_get_inode(sb, umode); + if (IS_ERR(ret)) { + err = PTR_ERR(ret); + ret = NULL; + goto error; } - v9fs_stat2inode(&fcall->params.rstat.stat, file_inode, sb); + v9fs_stat2inode(&fcall->params.rstat.stat, ret, sb); kfree(fcall); - fcall = NULL; - file_dentry->d_op = &v9fs_dentry_operations; - d_instantiate(file_dentry, file_inode); - - return 0; + return ret; - CleanUpFid: +error: kfree(fcall); - fcall = NULL; + if (ret) + iput(ret); - if (newfid >= 0) { - err = v9fs_t_clunk(v9ses, newfid); - if (err < 0) - dprintk(DEBUG_ERROR, "clunk failed: %d\n", err); - } - if (wfidno >= 0) { - err = v9fs_t_clunk(v9ses, wfidno); - if (err < 0) - dprintk(DEBUG_ERROR, "clunk failed: %d\n", err); - } - return result; + return ERR_PTR(err); } /** @@ -440,20 +436,97 @@ static int v9fs_remove(struct inode *dir, struct dentry *file, int rmdir) return result; } +static int +v9fs_open_created(struct inode *inode, struct file *file) +{ + return 0; +} + /** * v9fs_vfs_create - VFS hook to create files * @inode: directory inode that is being deleted * @dentry: dentry that is being deleted - * @perm: create permissions + * @mode: create permissions * @nd: path information * */ static int -v9fs_vfs_create(struct inode *inode, struct dentry *dentry, int perm, +v9fs_vfs_create(struct inode *dir, struct dentry *dentry, int mode, struct nameidata *nd) { - return v9fs_create(inode, dentry, perm, O_RDWR); + int err; + u32 fid, perm, iounit; + int flags; + struct v9fs_session_info *v9ses; + struct v9fs_fid *dfid, *vfid, *ffid; + struct inode *inode; + struct v9fs_qid qid; + struct file *filp; + + inode = NULL; + vfid = NULL; + v9ses = v9fs_inode2v9ses(dir); + dfid = v9fs_fid_lookup(dentry->d_parent); + perm = unixmode2p9mode(v9ses, mode); + + if (nd && nd->flags & LOOKUP_OPEN) + flags = nd->intent.open.flags - 1; + else + flags = O_RDWR; + + err = v9fs_create(v9ses, dfid->fid, (char *) dentry->d_name.name, + perm, v9fs_uflags2omode(flags), &fid, &qid, &iounit); + + if (err) + goto error; + + vfid = v9fs_clone_walk(v9ses, dfid->fid, dentry); + if (IS_ERR(vfid)) { + err = PTR_ERR(vfid); + vfid = NULL; + goto error; + } + + inode = v9fs_inode_from_fid(v9ses, vfid->fid, dir->i_sb); + if (IS_ERR(inode)) { + err = PTR_ERR(inode); + inode = NULL; + goto error; + } + + dentry->d_op = &v9fs_dentry_operations; + d_instantiate(dentry, inode); + + if (nd && nd->flags & LOOKUP_OPEN) { + ffid = v9fs_fid_create(v9ses, fid); + if (!ffid) + return -ENOMEM; + + filp = lookup_instantiate_filp(nd, dentry, v9fs_open_created); + if (IS_ERR(filp)) { + v9fs_fid_destroy(ffid); + return PTR_ERR(filp); + } + + ffid->rdir_pos = 0; + ffid->rdir_fcall = NULL; + ffid->fidopen = 1; + ffid->iounit = iounit; + ffid->filp = filp; + filp->private_data = ffid; + } + + return 0; + +error: + if (vfid) + v9fs_fid_destroy(vfid); + + if (inode) + iput(inode); + + return err; } /** @@ -464,9 +537,57 @@ v9fs_vfs_create(struct inode *inode, struct dentry *dentry, int perm, * */ -static int v9fs_vfs_mkdir(struct inode *inode, struct dentry *dentry, int mode) +static int v9fs_vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode) { - return v9fs_create(inode, dentry, mode | S_IFDIR, O_RDONLY); + int err; + u32 fid, perm; + struct v9fs_session_info *v9ses; + struct v9fs_fid *dfid, *vfid; + struct inode *inode; + + inode = NULL; + vfid = NULL; + v9ses = v9fs_inode2v9ses(dir); + dfid = v9fs_fid_lookup(dentry->d_parent); + perm = unixmode2p9mode(v9ses, mode | S_IFDIR); + + err = v9fs_create(v9ses, dfid->fid, (char *) dentry->d_name.name, + perm, V9FS_OREAD, &fid, NULL, NULL); + + if (err) { + dprintk(DEBUG_ERROR, "create error %d\n", err); + goto error; + } + + err = v9fs_t_clunk(v9ses, fid); + if (err) { + dprintk(DEBUG_ERROR, "clunk error %d\n", err); + goto error; + } + + vfid = v9fs_clone_walk(v9ses, dfid->fid, dentry); + if (IS_ERR(vfid)) { + err = PTR_ERR(vfid); + vfid = NULL; + goto error; + } + + inode = v9fs_inode_from_fid(v9ses, vfid->fid, dir->i_sb); + if (IS_ERR(inode)) { + err = PTR_ERR(inode); + inode = NULL; + goto error; + } + + dentry->d_op = &v9fs_dentry_operations; + d_instantiate(dentry, inode); + return 0; + +error: + if (vfid) + v9fs_fid_destroy(vfid); + + return err; } /** @@ -516,9 +637,8 @@ static struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry, return ERR_PTR(-ENOSPC); } - result = - v9fs_t_walk(v9ses, dirfidnum, newfid, (char *)dentry->d_name.name, - NULL); + result = v9fs_t_walk(v9ses, dirfidnum, newfid, + (char *)dentry->d_name.name, NULL); if (result < 0) { v9fs_put_idpool(newfid, &v9ses->fidpool); if (result == -ENOENT) { @@ -551,13 +671,17 @@ static struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry, inode->i_ino = v9fs_qid2ino(&fcall->params.rstat.stat.qid); - fid = v9fs_fid_create(dentry, v9ses, newfid, 0); + fid = v9fs_fid_create(v9ses, newfid); if (fid == NULL) { dprintk(DEBUG_ERROR, "couldn't insert\n"); result = -ENOMEM; goto FreeFcall; } + result = v9fs_fid_insert(fid, dentry); + if (result < 0) + goto FreeFcall; + fid->qid = fcall->params.rstat.stat.qid; dentry->d_op = &v9fs_dentry_operations; @@ -886,8 +1010,8 @@ static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen) } /* copy extension buffer into buffer */ - if (fcall->params.rstat.stat.extension.len+1 < buflen) - buflen = fcall->params.rstat.stat.extension.len + 1; + if (fcall->params.rstat.stat.extension.len < buflen) + buflen = fcall->params.rstat.stat.extension.len; memcpy(buffer, fcall->params.rstat.stat.extension.str, buflen - 1); buffer[buflen-1] = 0; @@ -951,7 +1075,7 @@ static void *v9fs_vfs_follow_link(struct dentry *dentry, struct nameidata *nd) if (!link) link = ERR_PTR(-ENOMEM); else { - len = v9fs_readlink(dentry, link, PATH_MAX); + len = v9fs_readlink(dentry, link, strlen(link)); if (len < 0) { __putname(link); @@ -983,53 +1107,75 @@ static void v9fs_vfs_put_link(struct dentry *dentry, struct nameidata *nd, void static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry, int mode, const char *extension) { - int err, retval; + int err; + u32 fid, perm; struct v9fs_session_info *v9ses; + struct v9fs_fid *dfid, *vfid; + struct inode *inode; struct v9fs_fcall *fcall; - struct v9fs_fid *fid; struct v9fs_wstat wstat; - v9ses = v9fs_inode2v9ses(dir); - retval = -EPERM; fcall = NULL; + inode = NULL; + vfid = NULL; + v9ses = v9fs_inode2v9ses(dir); + dfid = v9fs_fid_lookup(dentry->d_parent); + perm = unixmode2p9mode(v9ses, mode); if (!v9ses->extended) { dprintk(DEBUG_ERROR, "not extended\n"); - goto free_mem; + return -EPERM; } - /* issue a create */ - retval = v9fs_create(dir, dentry, mode, 0); - if (retval != 0) - goto free_mem; + err = v9fs_create(v9ses, dfid->fid, (char *) dentry->d_name.name, + perm, V9FS_OREAD, &fid, NULL, NULL); - fid = v9fs_fid_get_created(dentry); - if (!fid) { - dprintk(DEBUG_ERROR, "couldn't resolve fid from dentry\n"); - goto free_mem; + if (err) + goto error; + + err = v9fs_t_clunk(v9ses, fid); + if (err) + goto error; + + vfid = v9fs_clone_walk(v9ses, dfid->fid, dentry); + if (IS_ERR(vfid)) { + err = PTR_ERR(vfid); + vfid = NULL; + goto error; + } + + inode = v9fs_inode_from_fid(v9ses, vfid->fid, dir->i_sb); + if (IS_ERR(inode)) { + err = PTR_ERR(inode); + inode = NULL; + goto error; } /* issue a Twstat */ v9fs_blank_wstat(&wstat); wstat.muid = v9ses->name; wstat.extension = (char *) extension; - retval = v9fs_t_wstat(v9ses, fid->fid, &wstat, &fcall); - if (retval < 0) { - PRINT_FCALL_ERROR("wstat error", fcall); - goto free_mem; - } - - err = v9fs_t_clunk(v9ses, fid->fid); + err = v9fs_t_wstat(v9ses, vfid->fid, &wstat, &fcall); if (err < 0) { - dprintk(DEBUG_ERROR, "clunk failed: %d\n", err); - goto free_mem; + PRINT_FCALL_ERROR("wstat error", fcall); + goto error; } - d_drop(dentry); /* FID - will this also clunk? */ + kfree(fcall); + dentry->d_op = &v9fs_dentry_operations; + d_instantiate(dentry, inode); + return 0; -free_mem: +error: kfree(fcall); - return retval; + if (vfid) + v9fs_fid_destroy(vfid); + + if (inode) + iput(inode); + + return err; + } /** |