That patch looks fine by me. Happy to put it in the queue. Thanks Al. On Tue, Apr 14, 2015 at 11:07 AM Al Viro <v...@zeniv.linux.org.uk> wrote:
> On Mon, Apr 13, 2015 at 04:05:28PM +0000, Eric Van Hensbergen wrote: > > Well, technically fid 3 isn't 'open', only fid 2 is open - at least > > according to the protocol. fid 3 and fid 2 are both clones of fid 1. > > However, thanks for the alternative workaround. If you get a chance, can > > you check that my change to the client to partially fix this for the > other > > servers doesn't break nfs-ganesha: > > > > > https://github.com/ericvh/linux/commit/fddc7721d6d19e4e6be4905f37ade5b0521f4ed5 > > BTW, what the hell is going on in v9fs_vfs_mknod() and v9fs_vfs_link()? > You allocate 4Kb buffer, sprintf into it ("b %u %u", "c %u %u", or "%d\n") > feed it to v9fs_vfs_mkspecial() and immediately free it. What's wrong with > a local array of char? In the worst case it needs to be char name[24] - > surely, we are not so tight on stack that extra 16 bytes (that array > instead > of a pointer) would drive us over the cliff? > > IOW, do you have any problem with this: > diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c > index 703342e..cda68f7 100644 > --- a/fs/9p/vfs_inode.c > +++ b/fs/9p/vfs_inode.c > @@ -1370,6 +1370,8 @@ v9fs_vfs_symlink(struct inode *dir, struct dentry > *dentry, const char *symname) > return v9fs_vfs_mkspecial(dir, dentry, P9_DMSYMLINK, symname); > } > > +#define U32_MAX_DIGITS 10 > + > /** > * v9fs_vfs_link - create a hardlink > * @old_dentry: dentry for file to link to > @@ -1383,7 +1385,7 @@ v9fs_vfs_link(struct dentry *old_dentry, struct > inode *dir, > struct dentry *dentry) > { > int retval; > - char *name; > + char name[1 + U32_MAX_DIGITS + 2]; /* sign + number + \n + \0 */ > struct p9_fid *oldfid; > > p9_debug(P9_DEBUG_VFS, " %lu,%pd,%pd\n", > @@ -1393,20 +1395,12 @@ v9fs_vfs_link(struct dentry *old_dentry, struct > inode *dir, > if (IS_ERR(oldfid)) > return PTR_ERR(oldfid); > > - name = __getname(); > - if (unlikely(!name)) { > - retval = -ENOMEM; > - goto clunk_fid; > - } > - > sprintf(name, "%d\n", oldfid->fid); > retval = v9fs_vfs_mkspecial(dir, dentry, P9_DMLINK, name); > - __putname(name); > if (!retval) { > v9fs_refresh_inode(oldfid, d_inode(old_dentry)); > v9fs_invalidate_inode_attr(dir); > } > -clunk_fid: > p9_client_clunk(oldfid); > return retval; > } > @@ -1425,7 +1419,7 @@ v9fs_vfs_mknod(struct inode *dir, struct dentry > *dentry, umode_t mode, dev_t rde > { > struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dir); > int retval; > - char *name; > + char name[2 + U32_MAX_DIGITS + 1 + U32_MAX_DIGITS + 1]; > u32 perm; > > p9_debug(P9_DEBUG_VFS, " %lu,%pd mode: %hx MAJOR: %u MINOR: %u\n", > @@ -1435,26 +1429,16 @@ v9fs_vfs_mknod(struct inode *dir, struct dentry > *dentry, umode_t mode, dev_t rde > if (!new_valid_dev(rdev)) > return -EINVAL; > > - name = __getname(); > - if (!name) > - return -ENOMEM; > /* build extension */ > if (S_ISBLK(mode)) > sprintf(name, "b %u %u", MAJOR(rdev), MINOR(rdev)); > else if (S_ISCHR(mode)) > sprintf(name, "c %u %u", MAJOR(rdev), MINOR(rdev)); > - else if (S_ISFIFO(mode)) > - *name = 0; > - else if (S_ISSOCK(mode)) > + else > *name = 0; > - else { > - __putname(name); > - return -EINVAL; > - } > > perm = unixmode2p9mode(v9ses, mode); > retval = v9fs_vfs_mkspecial(dir, dentry, perm, name); > - __putname(name); > > return retval; > } >
