[PATCH] 9p: fix segfault caused by race condition in meta-data operations
Running dbench multithreaded exposed a race condition where fid structures were removed while in use. This patch adds semaphores to meta-data operations to protect the fid structure. Some cleanup of error-case handling in the inode operations is also included. Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Eric Van Hensbergen
Linus Torvalds
parent
ff76e1dfc8
commit
da977b2c7e
4 changed files with 196 additions and 129 deletions
69
fs/9p/fid.c
69
fs/9p/fid.c
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@ -25,6 +25,7 @@
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#include <linux/fs.h>
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#include <linux/sched.h>
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#include <linux/idr.h>
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#include <asm/semaphore.h>
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#include "debug.h"
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#include "v9fs.h"
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@ -84,6 +85,7 @@ struct v9fs_fid *v9fs_fid_create(struct v9fs_session_info *v9ses, int fid)
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new->iounit = 0;
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new->rdir_pos = 0;
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new->rdir_fcall = NULL;
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init_MUTEX(&new->lock);
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INIT_LIST_HEAD(&new->list);
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return new;
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@ -102,11 +104,11 @@ void v9fs_fid_destroy(struct v9fs_fid *fid)
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}
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/**
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* v9fs_fid_lookup - retrieve the right fid from a particular dentry
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* v9fs_fid_lookup - return a locked fid from a dentry
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* @dentry: dentry to look for fid in
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* @type: intent of lookup (operation or traversal)
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*
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* find a fid in the dentry
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* find a fid in the dentry, obtain its semaphore and return a reference to it.
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* code calling lookup is responsible for releasing lock
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*
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* TODO: only match fids that have the same uid as current user
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*
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@ -124,7 +126,68 @@ struct v9fs_fid *v9fs_fid_lookup(struct dentry *dentry)
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if (!return_fid) {
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dprintk(DEBUG_ERROR, "Couldn't find a fid in dentry\n");
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return_fid = ERR_PTR(-EBADF);
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}
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if(down_interruptible(&return_fid->lock))
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return ERR_PTR(-EINTR);
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return return_fid;
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}
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/**
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* v9fs_fid_clone - lookup the fid for a dentry, clone a private copy and release it
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* @dentry: dentry to look for fid in
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*
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* find a fid in the dentry and then clone to a new private fid
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*
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* TODO: only match fids that have the same uid as current user
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*
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*/
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struct v9fs_fid *v9fs_fid_clone(struct dentry *dentry)
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{
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struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dentry->d_inode);
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struct v9fs_fid *base_fid, *new_fid = ERR_PTR(-EBADF);
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struct v9fs_fcall *fcall = NULL;
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int fid, err;
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base_fid = v9fs_fid_lookup(dentry);
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if(IS_ERR(base_fid))
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return base_fid;
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if(base_fid) { /* clone fid */
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fid = v9fs_get_idpool(&v9ses->fidpool);
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if (fid < 0) {
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eprintk(KERN_WARNING, "newfid fails!\n");
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new_fid = ERR_PTR(-ENOSPC);
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goto Release_Fid;
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}
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err = v9fs_t_walk(v9ses, base_fid->fid, fid, NULL, &fcall);
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if (err < 0) {
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dprintk(DEBUG_ERROR, "clone walk didn't work\n");
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v9fs_put_idpool(fid, &v9ses->fidpool);
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new_fid = ERR_PTR(err);
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goto Free_Fcall;
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}
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new_fid = v9fs_fid_create(v9ses, fid);
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if (new_fid == NULL) {
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dprintk(DEBUG_ERROR, "out of memory\n");
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new_fid = ERR_PTR(-ENOMEM);
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}
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Free_Fcall:
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kfree(fcall);
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}
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Release_Fid:
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up(&base_fid->lock);
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return new_fid;
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}
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void v9fs_fid_clunk(struct v9fs_session_info *v9ses, struct v9fs_fid *fid)
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{
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v9fs_t_clunk(v9ses, fid->fid);
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v9fs_fid_destroy(fid);
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}
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@ -30,6 +30,8 @@ struct v9fs_fid {
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struct list_head list; /* list of fids associated with a dentry */
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struct list_head active; /* XXX - debug */
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struct semaphore lock;
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u32 fid;
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unsigned char fidopen; /* set when fid is opened */
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unsigned char fidclunked; /* set when fid has already been clunked */
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@ -55,3 +57,6 @@ struct v9fs_fid *v9fs_fid_get_created(struct dentry *);
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void v9fs_fid_destroy(struct v9fs_fid *fid);
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struct v9fs_fid *v9fs_fid_create(struct v9fs_session_info *, int fid);
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int v9fs_fid_insert(struct v9fs_fid *fid, struct dentry *dentry);
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struct v9fs_fid *v9fs_fid_clone(struct dentry *dentry);
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void v9fs_fid_clunk(struct v9fs_session_info *v9ses, struct v9fs_fid *fid);
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@ -55,53 +55,22 @@ int v9fs_file_open(struct inode *inode, struct file *file)
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struct v9fs_fid *vfid;
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struct v9fs_fcall *fcall = NULL;
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int omode;
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int fid = V9FS_NOFID;
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int err;
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dprintk(DEBUG_VFS, "inode: %p file: %p \n", inode, file);
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vfid = v9fs_fid_lookup(file->f_path.dentry);
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if (!vfid) {
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dprintk(DEBUG_ERROR, "Couldn't resolve fid from dentry\n");
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return -EBADF;
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}
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vfid = v9fs_fid_clone(file->f_path.dentry);
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if (IS_ERR(vfid))
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return PTR_ERR(vfid);
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fid = v9fs_get_idpool(&v9ses->fidpool);
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if (fid < 0) {
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eprintk(KERN_WARNING, "newfid fails!\n");
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return -ENOSPC;
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}
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err = v9fs_t_walk(v9ses, vfid->fid, fid, NULL, &fcall);
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if (err < 0) {
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dprintk(DEBUG_ERROR, "rewalk didn't work\n");
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if (fcall && fcall->id == RWALK)
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goto clunk_fid;
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else {
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v9fs_put_idpool(fid, &v9ses->fidpool);
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goto free_fcall;
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}
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}
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kfree(fcall);
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/* TODO: do special things for O_EXCL, O_NOFOLLOW, O_SYNC */
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/* translate open mode appropriately */
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omode = v9fs_uflags2omode(file->f_flags);
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err = v9fs_t_open(v9ses, fid, omode, &fcall);
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err = v9fs_t_open(v9ses, vfid->fid, omode, &fcall);
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if (err < 0) {
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PRINT_FCALL_ERROR("open failed", fcall);
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goto clunk_fid;
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}
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vfid = kmalloc(sizeof(struct v9fs_fid), GFP_KERNEL);
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if (vfid == NULL) {
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dprintk(DEBUG_ERROR, "out of memory\n");
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err = -ENOMEM;
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goto clunk_fid;
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goto Clunk_Fid;
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}
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file->private_data = vfid;
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vfid->fid = fid;
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vfid->fidopen = 1;
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vfid->fidclunked = 0;
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vfid->iounit = fcall->params.ropen.iounit;
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@ -112,10 +81,8 @@ int v9fs_file_open(struct inode *inode, struct file *file)
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return 0;
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clunk_fid:
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v9fs_t_clunk(v9ses, fid);
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free_fcall:
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Clunk_Fid:
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v9fs_fid_clunk(v9ses, vfid);
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kfree(fcall);
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return err;
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@ -416,12 +416,8 @@ static int v9fs_remove(struct inode *dir, struct dentry *file, int rmdir)
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sb = file_inode->i_sb;
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v9ses = v9fs_inode2v9ses(file_inode);
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v9fid = v9fs_fid_lookup(file);
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if (!v9fid) {
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dprintk(DEBUG_ERROR,
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"no v9fs_fid\n");
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return -EBADF;
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}
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if(IS_ERR(v9fid))
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return PTR_ERR(v9fid);
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fid = v9fid->fid;
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if (fid < 0) {
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@ -433,11 +429,13 @@ static int v9fs_remove(struct inode *dir, struct dentry *file, int rmdir)
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result = v9fs_t_remove(v9ses, fid, &fcall);
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if (result < 0) {
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PRINT_FCALL_ERROR("remove fails", fcall);
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goto Error;
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}
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v9fs_put_idpool(fid, &v9ses->fidpool);
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v9fs_fid_destroy(v9fid);
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Error:
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kfree(fcall);
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return result;
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}
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@ -473,9 +471,13 @@ v9fs_vfs_create(struct inode *dir, struct dentry *dentry, int mode,
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inode = NULL;
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vfid = NULL;
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v9ses = v9fs_inode2v9ses(dir);
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dfid = v9fs_fid_lookup(dentry->d_parent);
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perm = unixmode2p9mode(v9ses, mode);
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dfid = v9fs_fid_clone(dentry->d_parent);
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if(IS_ERR(dfid)) {
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err = PTR_ERR(dfid);
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goto error;
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}
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perm = unixmode2p9mode(v9ses, mode);
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if (nd && nd->flags & LOOKUP_OPEN)
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flags = nd->intent.open.flags - 1;
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else
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@ -485,9 +487,10 @@ v9fs_vfs_create(struct inode *dir, struct dentry *dentry, int mode,
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perm, v9fs_uflags2omode(flags), NULL, &fid, &qid, &iounit);
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if (err)
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goto error;
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goto clunk_dfid;
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vfid = v9fs_clone_walk(v9ses, dfid->fid, dentry);
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v9fs_fid_clunk(v9ses, dfid);
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if (IS_ERR(vfid)) {
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err = PTR_ERR(vfid);
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vfid = NULL;
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@ -525,6 +528,9 @@ v9fs_vfs_create(struct inode *dir, struct dentry *dentry, int mode,
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return 0;
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clunk_dfid:
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v9fs_fid_clunk(v9ses, dfid);
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error:
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if (vfid)
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v9fs_fid_destroy(vfid);
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@ -551,7 +557,12 @@ static int v9fs_vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
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inode = NULL;
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vfid = NULL;
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v9ses = v9fs_inode2v9ses(dir);
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dfid = v9fs_fid_lookup(dentry->d_parent);
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dfid = v9fs_fid_clone(dentry->d_parent);
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if(IS_ERR(dfid)) {
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err = PTR_ERR(dfid);
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goto error;
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}
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perm = unixmode2p9mode(v9ses, mode | S_IFDIR);
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err = v9fs_create(v9ses, dfid->fid, (char *) dentry->d_name.name,
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@ -559,37 +570,36 @@ static int v9fs_vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
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if (err) {
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dprintk(DEBUG_ERROR, "create error %d\n", err);
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goto error;
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}
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err = v9fs_t_clunk(v9ses, fid);
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if (err) {
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dprintk(DEBUG_ERROR, "clunk error %d\n", err);
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goto error;
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goto clean_up_dfid;
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}
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vfid = v9fs_clone_walk(v9ses, dfid->fid, dentry);
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if (IS_ERR(vfid)) {
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err = PTR_ERR(vfid);
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vfid = NULL;
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goto error;
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goto clean_up_dfid;
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}
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v9fs_fid_clunk(v9ses, dfid);
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inode = v9fs_inode_from_fid(v9ses, vfid->fid, dir->i_sb);
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if (IS_ERR(inode)) {
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err = PTR_ERR(inode);
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inode = NULL;
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goto error;
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goto clean_up_fids;
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}
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dentry->d_op = &v9fs_dentry_operations;
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d_instantiate(dentry, inode);
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return 0;
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error:
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clean_up_fids:
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if (vfid)
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v9fs_fid_destroy(vfid);
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clean_up_dfid:
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v9fs_fid_clunk(v9ses, dfid);
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error:
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return err;
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}
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@ -622,28 +632,23 @@ static struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
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dentry->d_op = &v9fs_dentry_operations;
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dirfid = v9fs_fid_lookup(dentry->d_parent);
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if (!dirfid) {
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dprintk(DEBUG_ERROR, "no dirfid\n");
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return ERR_PTR(-EINVAL);
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}
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if(IS_ERR(dirfid))
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return ERR_PTR(PTR_ERR(dirfid));
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dirfidnum = dirfid->fid;
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if (dirfidnum < 0) {
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dprintk(DEBUG_ERROR, "no dirfid for inode %p, #%lu\n",
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dir, dir->i_ino);
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return ERR_PTR(-EBADF);
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}
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newfid = v9fs_get_idpool(&v9ses->fidpool);
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if (newfid < 0) {
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eprintk(KERN_WARNING, "newfid fails!\n");
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return ERR_PTR(-ENOSPC);
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result = -ENOSPC;
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goto Release_Dirfid;
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}
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result = v9fs_t_walk(v9ses, dirfidnum, newfid,
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(char *)dentry->d_name.name, &fcall);
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up(&dirfid->lock);
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if (result < 0) {
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if (fcall && fcall->id == RWALK)
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v9fs_t_clunk(v9ses, newfid);
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@ -701,8 +706,12 @@ static struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
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return NULL;
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FreeFcall:
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Release_Dirfid:
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up(&dirfid->lock);
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FreeFcall:
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kfree(fcall);
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return ERR_PTR(result);
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}
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@ -746,10 +755,8 @@ v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
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struct inode *old_inode = old_dentry->d_inode;
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struct v9fs_session_info *v9ses = v9fs_inode2v9ses(old_inode);
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struct v9fs_fid *oldfid = v9fs_fid_lookup(old_dentry);
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struct v9fs_fid *olddirfid =
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v9fs_fid_lookup(old_dentry->d_parent);
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struct v9fs_fid *newdirfid =
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v9fs_fid_lookup(new_dentry->d_parent);
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struct v9fs_fid *olddirfid;
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struct v9fs_fid *newdirfid;
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struct v9fs_wstat wstat;
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struct v9fs_fcall *fcall = NULL;
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int fid = -1;
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@ -759,16 +766,26 @@ v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
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dprintk(DEBUG_VFS, "\n");
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if ((!oldfid) || (!olddirfid) || (!newdirfid)) {
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dprintk(DEBUG_ERROR, "problem with arguments\n");
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return -EBADF;
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if(IS_ERR(oldfid))
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return PTR_ERR(oldfid);
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olddirfid = v9fs_fid_clone(old_dentry->d_parent);
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if(IS_ERR(olddirfid)) {
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retval = PTR_ERR(olddirfid);
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goto Release_lock;
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}
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newdirfid = v9fs_fid_clone(new_dentry->d_parent);
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if(IS_ERR(newdirfid)) {
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retval = PTR_ERR(newdirfid);
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goto Clunk_olddir;
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}
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/* 9P can only handle file rename in the same directory */
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if (memcmp(&olddirfid->qid, &newdirfid->qid, sizeof(newdirfid->qid))) {
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dprintk(DEBUG_ERROR, "old dir and new dir are different\n");
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retval = -EXDEV;
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goto FreeFcallnBail;
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goto Clunk_newdir;
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}
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fid = oldfid->fid;
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@ -779,7 +796,7 @@ v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
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dprintk(DEBUG_ERROR, "no fid for old file #%lu\n",
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old_inode->i_ino);
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retval = -EBADF;
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goto FreeFcallnBail;
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goto Clunk_newdir;
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}
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v9fs_blank_wstat(&wstat);
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||||
|
|
@ -788,11 +805,20 @@ v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
|
|||
|
||||
retval = v9fs_t_wstat(v9ses, fid, &wstat, &fcall);
|
||||
|
||||
FreeFcallnBail:
|
||||
if (retval < 0)
|
||||
PRINT_FCALL_ERROR("wstat error", fcall);
|
||||
|
||||
kfree(fcall);
|
||||
|
||||
Clunk_newdir:
|
||||
v9fs_fid_clunk(v9ses, newdirfid);
|
||||
|
||||
Clunk_olddir:
|
||||
v9fs_fid_clunk(v9ses, olddirfid);
|
||||
|
||||
Release_lock:
|
||||
up(&oldfid->lock);
|
||||
|
||||
return retval;
|
||||
}
|
||||
|
||||
|
|
@ -810,15 +836,12 @@ v9fs_vfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
|
|||
{
|
||||
struct v9fs_fcall *fcall = NULL;
|
||||
struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dentry->d_inode);
|
||||
struct v9fs_fid *fid = v9fs_fid_lookup(dentry);
|
||||
struct v9fs_fid *fid = v9fs_fid_clone(dentry);
|
||||
int err = -EPERM;
|
||||
|
||||
dprintk(DEBUG_VFS, "dentry: %p\n", dentry);
|
||||
if (!fid) {
|
||||
dprintk(DEBUG_ERROR,
|
||||
"couldn't find fid associated with dentry\n");
|
||||
return -EBADF;
|
||||
}
|
||||
if(IS_ERR(fid))
|
||||
return PTR_ERR(fid);
|
||||
|
||||
err = v9fs_t_stat(v9ses, fid->fid, &fcall);
|
||||
|
||||
|
|
@ -831,6 +854,7 @@ v9fs_vfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
|
|||
}
|
||||
|
||||
kfree(fcall);
|
||||
v9fs_fid_clunk(v9ses, fid);
|
||||
return err;
|
||||
}
|
||||
|
||||
|
|
@ -844,18 +868,14 @@ v9fs_vfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
|
|||
static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr)
|
||||
{
|
||||
struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dentry->d_inode);
|
||||
struct v9fs_fid *fid = v9fs_fid_lookup(dentry);
|
||||
struct v9fs_fid *fid = v9fs_fid_clone(dentry);
|
||||
struct v9fs_fcall *fcall = NULL;
|
||||
struct v9fs_wstat wstat;
|
||||
int res = -EPERM;
|
||||
|
||||
dprintk(DEBUG_VFS, "\n");
|
||||
|
||||
if (!fid) {
|
||||
dprintk(DEBUG_ERROR,
|
||||
"Couldn't find fid associated with dentry\n");
|
||||
return -EBADF;
|
||||
}
|
||||
if(IS_ERR(fid))
|
||||
return PTR_ERR(fid);
|
||||
|
||||
v9fs_blank_wstat(&wstat);
|
||||
if (iattr->ia_valid & ATTR_MODE)
|
||||
|
|
@ -887,6 +907,7 @@ static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr)
|
|||
if (res >= 0)
|
||||
res = inode_setattr(dentry->d_inode, iattr);
|
||||
|
||||
v9fs_fid_clunk(v9ses, fid);
|
||||
return res;
|
||||
}
|
||||
|
||||
|
|
@ -987,18 +1008,15 @@ static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen)
|
|||
|
||||
struct v9fs_fcall *fcall = NULL;
|
||||
struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dentry->d_inode);
|
||||
struct v9fs_fid *fid = v9fs_fid_lookup(dentry);
|
||||
struct v9fs_fid *fid = v9fs_fid_clone(dentry);
|
||||
|
||||
if (!fid) {
|
||||
dprintk(DEBUG_ERROR, "could not resolve fid from dentry\n");
|
||||
retval = -EBADF;
|
||||
goto FreeFcall;
|
||||
}
|
||||
if(IS_ERR(fid))
|
||||
return PTR_ERR(fid);
|
||||
|
||||
if (!v9ses->extended) {
|
||||
retval = -EBADF;
|
||||
dprintk(DEBUG_ERROR, "not extended\n");
|
||||
goto FreeFcall;
|
||||
goto ClunkFid;
|
||||
}
|
||||
|
||||
dprintk(DEBUG_VFS, " %s\n", dentry->d_name.name);
|
||||
|
|
@ -1009,8 +1027,10 @@ static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen)
|
|||
goto FreeFcall;
|
||||
}
|
||||
|
||||
if (!fcall)
|
||||
return -EIO;
|
||||
if (!fcall) {
|
||||
retval = -EIO;
|
||||
goto ClunkFid;
|
||||
}
|
||||
|
||||
if (!(fcall->params.rstat.stat.mode & V9FS_DMSYMLINK)) {
|
||||
retval = -EINVAL;
|
||||
|
|
@ -1028,9 +1048,12 @@ static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen)
|
|||
fcall->params.rstat.stat.extension.str, buffer);
|
||||
retval = buflen;
|
||||
|
||||
FreeFcall:
|
||||
FreeFcall:
|
||||
kfree(fcall);
|
||||
|
||||
ClunkFid:
|
||||
v9fs_fid_clunk(v9ses, fid);
|
||||
|
||||
return retval;
|
||||
}
|
||||
|
||||
|
|
@ -1123,52 +1146,58 @@ static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry,
|
|||
int err;
|
||||
u32 fid, perm;
|
||||
struct v9fs_session_info *v9ses;
|
||||
struct v9fs_fid *dfid, *vfid;
|
||||
struct inode *inode;
|
||||
struct v9fs_fid *dfid, *vfid = NULL;
|
||||
struct inode *inode = 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");
|
||||
return -EPERM;
|
||||
}
|
||||
|
||||
dfid = v9fs_fid_clone(dentry->d_parent);
|
||||
if(IS_ERR(dfid)) {
|
||||
err = PTR_ERR(dfid);
|
||||
goto error;
|
||||
}
|
||||
|
||||
perm = unixmode2p9mode(v9ses, mode);
|
||||
|
||||
err = v9fs_create(v9ses, dfid->fid, (char *) dentry->d_name.name,
|
||||
perm, V9FS_OREAD, (char *) extension, &fid, NULL, NULL);
|
||||
|
||||
if (err)
|
||||
goto error;
|
||||
goto clunk_dfid;
|
||||
|
||||
err = v9fs_t_clunk(v9ses, fid);
|
||||
if (err)
|
||||
goto error;
|
||||
goto clunk_dfid;
|
||||
|
||||
vfid = v9fs_clone_walk(v9ses, dfid->fid, dentry);
|
||||
if (IS_ERR(vfid)) {
|
||||
err = PTR_ERR(vfid);
|
||||
vfid = NULL;
|
||||
goto error;
|
||||
goto clunk_dfid;
|
||||
}
|
||||
|
||||
inode = v9fs_inode_from_fid(v9ses, vfid->fid, dir->i_sb);
|
||||
if (IS_ERR(inode)) {
|
||||
err = PTR_ERR(inode);
|
||||
inode = NULL;
|
||||
goto error;
|
||||
goto free_vfid;
|
||||
}
|
||||
|
||||
dentry->d_op = &v9fs_dentry_operations;
|
||||
d_instantiate(dentry, inode);
|
||||
return 0;
|
||||
|
||||
error:
|
||||
if (vfid)
|
||||
v9fs_fid_destroy(vfid);
|
||||
free_vfid:
|
||||
v9fs_fid_destroy(vfid);
|
||||
|
||||
clunk_dfid:
|
||||
v9fs_fid_clunk(v9ses, dfid);
|
||||
|
||||
error:
|
||||
return err;
|
||||
|
||||
}
|
||||
|
|
@ -1209,26 +1238,29 @@ v9fs_vfs_link(struct dentry *old_dentry, struct inode *dir,
|
|||
struct dentry *dentry)
|
||||
{
|
||||
int retval;
|
||||
struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dir);
|
||||
struct v9fs_fid *oldfid;
|
||||
char *name;
|
||||
|
||||
dprintk(DEBUG_VFS, " %lu,%s,%s\n", dir->i_ino, dentry->d_name.name,
|
||||
old_dentry->d_name.name);
|
||||
|
||||
oldfid = v9fs_fid_lookup(old_dentry);
|
||||
if (!oldfid) {
|
||||
dprintk(DEBUG_ERROR, "can't find oldfid\n");
|
||||
return -EPERM;
|
||||
}
|
||||
oldfid = v9fs_fid_clone(old_dentry);
|
||||
if(IS_ERR(oldfid))
|
||||
return PTR_ERR(oldfid);
|
||||
|
||||
name = __getname();
|
||||
if (unlikely(!name))
|
||||
return -ENOMEM;
|
||||
if (unlikely(!name)) {
|
||||
retval = -ENOMEM;
|
||||
goto clunk_fid;
|
||||
}
|
||||
|
||||
sprintf(name, "%d\n", oldfid->fid);
|
||||
retval = v9fs_vfs_mkspecial(dir, dentry, V9FS_DMLINK, name);
|
||||
__putname(name);
|
||||
|
||||
clunk_fid:
|
||||
v9fs_fid_clunk(v9ses, oldfid);
|
||||
return retval;
|
||||
}
|
||||
|
||||
|
|
|
|||
Loading…
Reference in a new issue