[PATCH] v9fs: handle kthread_create failure, minor bugfixes

- remove unnecessary -ENOMEM assignments
- return correct value when buf_check_size for second time in a buffer
- handle failures when create_workqueue and kthread_create are called
- use kzalloc instead of kmalloc/memset 0
- v9fs_str_copy and v9fs_str_compare were buggy, were used only in one
  place, correct the logic and move it to the place it is used.

Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Cc: Eric Van Hensbergen <ericvh@ericvh.myip.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/fs/9p/9p.c b/fs/9p/9p.c
index dc3ce44..1a6d087 100644 (file)
--- a/fs/9p/9p.c
+++ b/fs/9p/9p.c
@@ -86,7 +86,6 @@ v9fs_t_attach(struct v9fs_session_info *v9ses, char *uname, char *aname,
        dprintk(DEBUG_9P, "uname '%s' aname '%s' fid %d afid %d\n", uname,
                aname, fid, afid);
 
-       ret = -ENOMEM;
        tc = v9fs_create_tattach(fid, afid, uname, aname);
        if (!IS_ERR(tc)) {
                ret = v9fs_mux_rpc(v9ses->mux, tc, rcp);
@@ -136,7 +135,6 @@ v9fs_t_clunk(struct v9fs_session_info *v9ses, u32 fid)
 
        dprintk(DEBUG_9P, "fid %d\n", fid);
 
-       ret = -ENOMEM;
        rc = NULL;
        tc = v9fs_create_tclunk(fid);
        if (!IS_ERR(tc))
@@ -165,7 +163,6 @@ int v9fs_t_flush(struct v9fs_session_info *v9ses, u16 oldtag)
 
        dprintk(DEBUG_9P, "oldtag %d\n", oldtag);
 
-       ret = -ENOMEM;
        tc = v9fs_create_tflush(oldtag);
        if (!IS_ERR(tc)) {
                ret = v9fs_mux_rpc(v9ses->mux, tc, NULL);
@@ -221,7 +218,6 @@ v9fs_t_wstat(struct v9fs_session_info *v9ses, u32 fid,
 
        dprintk(DEBUG_9P, "fid %d\n", fid);
 
-       ret = -ENOMEM;
        tc = v9fs_create_twstat(fid, wstat, v9ses->extended);
        if (!IS_ERR(tc)) {
                ret = v9fs_mux_rpc(v9ses->mux, tc, rcp);
@@ -259,7 +255,6 @@ v9fs_t_walk(struct v9fs_session_info *v9ses, u32 fid, u32 newfid,
        else
                nwname = 0;
 
-       ret = -ENOMEM;
        tc = v9fs_create_twalk(fid, newfid, nwname, &name);
        if (!IS_ERR(tc)) {
                ret = v9fs_mux_rpc(v9ses->mux, tc, rcp);
@@ -289,7 +284,6 @@ v9fs_t_open(struct v9fs_session_info *v9ses, u32 fid, u8 mode,
 
        dprintk(DEBUG_9P, "fid %d mode %d\n", fid, mode);
 
-       ret = -ENOMEM;
        tc = v9fs_create_topen(fid, mode);
        if (!IS_ERR(tc)) {
                ret = v9fs_mux_rpc(v9ses->mux, tc, rcp);
@@ -317,7 +311,6 @@ v9fs_t_remove(struct v9fs_session_info *v9ses, u32 fid,
 
        dprintk(DEBUG_9P, "fid %d\n", fid);
 
-       ret = -ENOMEM;
        tc = v9fs_create_tremove(fid);
        if (!IS_ERR(tc)) {
                ret = v9fs_mux_rpc(v9ses->mux, tc, rcp);
@@ -349,7 +342,6 @@ v9fs_t_create(struct v9fs_session_info *v9ses, u32 fid, char *name,
        dprintk(DEBUG_9P, "fid %d name '%s' perm %x mode %d\n",
                fid, name, perm, mode);
 
-       ret = -ENOMEM;
        tc = v9fs_create_tcreate(fid, name, perm, mode);
        if (!IS_ERR(tc)) {
                ret = v9fs_mux_rpc(v9ses->mux, tc, rcp);
@@ -380,7 +372,6 @@ v9fs_t_read(struct v9fs_session_info *v9ses, u32 fid, u64 offset,
        dprintk(DEBUG_9P, "fid %d offset 0x%llux count 0x%x\n", fid,
                (long long unsigned) offset, count);
 
-       ret = -ENOMEM;
        tc = v9fs_create_tread(fid, offset, count);
        if (!IS_ERR(tc)) {
                ret = v9fs_mux_rpc(v9ses->mux, tc, &rc);
@@ -418,7 +409,6 @@ v9fs_t_write(struct v9fs_session_info *v9ses, u32 fid, u64 offset, u32 count,
        dprintk(DEBUG_9P, "fid %d offset 0x%llux count 0x%x\n", fid,
                (long long unsigned) offset, count);
 
-       ret = -ENOMEM;
        tc = v9fs_create_twrite(fid, offset, count, data);
        if (!IS_ERR(tc)) {
                ret = v9fs_mux_rpc(v9ses->mux, tc, &rc);

diff --git a/fs/9p/9p.h b/fs/9p/9p.h
index 007ff63..0cd374d 100644 (file)
--- a/fs/9p/9p.h
+++ b/fs/9p/9p.h
@@ -340,9 +340,6 @@ struct v9fs_fcall {
        fcall?fcall->params.rerror.error.len:0, \
        fcall?fcall->params.rerror.error.str:"");
 
-char *v9fs_str_copy(char *buf, int buflen, struct v9fs_str *str);
-int v9fs_str_compare(char *buf, struct v9fs_str *str);
-
 int v9fs_t_version(struct v9fs_session_info *v9ses, u32 msize,
                   char *version, struct v9fs_fcall **rcall);
 

diff --git a/fs/9p/conv.c b/fs/9p/conv.c
index f62434d..55ccfa1 100644 (file)
--- a/fs/9p/conv.c
+++ b/fs/9p/conv.c
@@ -45,37 +45,6 @@ struct cbuf {
        unsigned char *ep;
 };
 
-char *v9fs_str_copy(char *buf, int buflen, struct v9fs_str *str)
-{
-       int n;
-
-       if (buflen < str->len)
-               n = buflen;
-       else
-               n = str->len;
-
-       memmove(buf, str->str, n - 1);
-
-       return buf;
-}
-
-int v9fs_str_compare(char *buf, struct v9fs_str *str)
-{
-       int n, ret;
-
-       ret = strncmp(buf, str->str, str->len);
-
-       if (!ret) {
-               n = strlen(buf);
-               if (n < str->len)
-                       ret = -1;
-               else if (n > str->len)
-                       ret = 1;
-       }
-
-       return ret;
-}
-
 static inline void buf_init(struct cbuf *buf, void *data, int datalen)
 {
        buf->sp = buf->p = data;
@@ -89,11 +58,14 @@ static inline int buf_check_overflow(struct cbuf *buf)
 
 static inline int buf_check_size(struct cbuf *buf, int len)
 {
-       if (buf->p + len > buf->ep && buf->p < buf->ep) {
-               eprintk(KERN_ERR, "buffer overflow: want %d has %d\n",
-                       len, (int)(buf->ep - buf->p));
-               dump_stack();
-               buf->p = buf->ep + 1;
+       if (buf->p + len > buf->ep) {
+               if (buf->p < buf->ep) {
+                       eprintk(KERN_ERR, "buffer overflow: want %d has %d\n",
+                               len, (int)(buf->ep - buf->p));
+                       dump_stack();
+                       buf->p = buf->ep + 1;
+               }
+
                return 0;
        }
 
@@ -527,6 +499,7 @@ v9fs_create_common(struct cbuf *bufp, u32 size, u8 id)
 
 void v9fs_set_tag(struct v9fs_fcall *fc, u16 tag)
 {
+       fc->tag = tag;
        *(__le16 *) (fc->sdata + 5) = cpu_to_le16(tag);
 }
 

diff --git a/fs/9p/error.h b/fs/9p/error.h
index 8b3176b..a9794e8 100644 (file)
--- a/fs/9p/error.h
+++ b/fs/9p/error.h
@@ -176,4 +176,3 @@ static struct errormap errmap[] = {
 };
 
 extern int v9fs_error_init(void);
-extern int v9fs_errstr2errno(char *errstr, int len);

diff --git a/fs/9p/mux.c b/fs/9p/mux.c
index f21cf50..945cb36 100644 (file)
--- a/fs/9p/mux.c
+++ b/fs/9p/mux.c
@@ -102,8 +102,6 @@ struct v9fs_mux_rpc {
        wait_queue_head_t wqueue;
 };
 
-extern int v9fs_errstr2errno(char *str, int len);
-
 static int v9fs_poll_proc(void *);
 static void v9fs_read_work(void *);
 static void v9fs_write_work(void *);
@@ -119,7 +117,7 @@ static int v9fs_mux_num;
 static int v9fs_mux_poll_task_num;
 static struct v9fs_mux_poll_task v9fs_mux_poll_tasks[100];
 
-void v9fs_mux_global_init(void)
+int v9fs_mux_global_init(void)
 {
        int i;
 
@@ -127,6 +125,10 @@ void v9fs_mux_global_init(void)
                v9fs_mux_poll_tasks[i].task = NULL;
 
        v9fs_mux_wq = create_workqueue("v9fs");
+       if (!v9fs_mux_wq)
+               return -ENOMEM;
+
+       return 0;
 }
 
 void v9fs_mux_global_exit(void)
@@ -156,10 +158,11 @@ inline int v9fs_mux_calc_poll_procs(int muxnum)
        return n;
 }
 
-static void v9fs_mux_poll_start(struct v9fs_mux_data *m)
+static int v9fs_mux_poll_start(struct v9fs_mux_data *m)
 {
        int i, n;
        struct v9fs_mux_poll_task *vpt, *vptlast;
+       struct task_struct *pproc;
 
        dprintk(DEBUG_MUX, "mux %p muxnum %d procnum %d\n", m, v9fs_mux_num,
                v9fs_mux_poll_task_num);
@@ -171,13 +174,16 @@ static void v9fs_mux_poll_start(struct v9fs_mux_data *m)
                        if (v9fs_mux_poll_tasks[i].task == NULL) {
                                vpt = &v9fs_mux_poll_tasks[i];
                                dprintk(DEBUG_MUX, "create proc %p\n", vpt);
-                               vpt->task =
-                                   kthread_create(v9fs_poll_proc, vpt,
+                               pproc = kthread_create(v9fs_poll_proc, vpt,
                                                   "v9fs-poll");
-                               INIT_LIST_HEAD(&vpt->mux_list);
-                               vpt->muxnum = 0;
-                               v9fs_mux_poll_task_num++;
-                               wake_up_process(vpt->task);
+
+                               if (!IS_ERR(pproc)) {
+                                       vpt->task = pproc;
+                                       INIT_LIST_HEAD(&vpt->mux_list);
+                                       vpt->muxnum = 0;
+                                       v9fs_mux_poll_task_num++;
+                                       wake_up_process(vpt->task);
+                               }
                                break;
                        }
                }
@@ -207,16 +213,21 @@ static void v9fs_mux_poll_start(struct v9fs_mux_data *m)
        }
 
        if (i >= ARRAY_SIZE(v9fs_mux_poll_tasks)) {
+               if (vptlast == NULL)
+                       return -ENOMEM;
+
                dprintk(DEBUG_MUX, "put in proc %d\n", i);
                list_add(&m->mux_list, &vptlast->mux_list);
                vptlast->muxnum++;
-               m->poll_task = vpt;
+               m->poll_task = vptlast;
                memset(&m->poll_waddr, 0, sizeof(m->poll_waddr));
                init_poll_funcptr(&m->pt, v9fs_pollwait);
        }
 
        v9fs_mux_num++;
        down(&v9fs_mux_task_lock);
+
+       return 0;
 }
 
 static void v9fs_mux_poll_stop(struct v9fs_mux_data *m)
@@ -283,7 +294,10 @@ struct v9fs_mux_data *v9fs_mux_init(struct v9fs_transport *trans, int msize,
        INIT_WORK(&m->wq, v9fs_write_work, m);
        m->wsched = 0;
        memset(&m->poll_waddr, 0, sizeof(m->poll_waddr));
-       v9fs_mux_poll_start(m);
+       m->poll_task = NULL;
+       n = v9fs_mux_poll_start(m);
+       if (n)
+               return ERR_PTR(n);
 
        n = trans->poll(trans, &m->pt);
        if (n & POLLIN) {

diff --git a/fs/9p/mux.h b/fs/9p/mux.h
index 02b13b1..9473b84 100644 (file)
--- a/fs/9p/mux.h
+++ b/fs/9p/mux.h
@@ -40,7 +40,7 @@ struct v9fs_mux_data;
 typedef void (*v9fs_mux_req_callback)(void *a, struct v9fs_fcall *tc,
        struct v9fs_fcall *rc, int err);
 
-void v9fs_mux_global_init(void);
+int v9fs_mux_global_init(void);
 void v9fs_mux_global_exit(void);
 
 struct v9fs_mux_data *v9fs_mux_init(struct v9fs_transport *trans, int msize,
@@ -55,3 +55,4 @@ int v9fs_mux_rpcnb(struct v9fs_mux_data *m, struct v9fs_fcall *tc,
 
 void v9fs_mux_flush(struct v9fs_mux_data *m, int sendflush);
 void v9fs_mux_cancel(struct v9fs_mux_data *m, int err);
+int v9fs_errstr2errno(char *errstr, int len);

diff --git a/fs/9p/v9fs.c b/fs/9p/v9fs.c
index 519b21d..5250c42 100644 (file)
--- a/fs/9p/v9fs.c
+++ b/fs/9p/v9fs.c
@@ -269,6 +269,7 @@ v9fs_session_init(struct v9fs_session_info *v9ses,
        int n = 0;
        int newfid = -1;
        int retval = -EINVAL;
+       struct v9fs_str *version;
 
        v9ses->name = __getname();
        if (!v9ses->name)
@@ -351,13 +352,16 @@ v9fs_session_init(struct v9fs_session_info *v9ses,
                        goto FreeFcall;
                }
 
-               /* Really should check for 9P1 and report error */
-               if (!v9fs_str_compare("9P2000.u", &fcall->params.rversion.version)) {
+               version = &fcall->params.rversion.version;
+               if (version->len==8 && !memcmp(version->str, "9P2000.u", 8)) {
                        dprintk(DEBUG_9P, "9P2000 UNIX extensions enabled\n");
                        v9ses->extended = 1;
-               } else {
+               } else if (version->len==6 && !memcmp(version->str, "9P2000", 6)) {
                        dprintk(DEBUG_9P, "9P2000 legacy mode enabled\n");
                        v9ses->extended = 0;
+               } else {
+                       retval = -EREMOTEIO;
+                       goto FreeFcall;
                }
 
                n = fcall->params.rversion.msize;
@@ -449,12 +453,17 @@ extern int v9fs_error_init(void);
 
 static int __init init_v9fs(void)
 {
+       int ret;
+
        v9fs_error_init();
 
        printk(KERN_INFO "Installing v9fs 9P2000 file system support\n");
 
-       v9fs_mux_global_init();
-       return register_filesystem(&v9fs_fs_type);
+       ret = v9fs_mux_global_init();
+       if (!ret)
+               ret = register_filesystem(&v9fs_fs_type);
+
+       return ret;
 }
 
 /**

diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index 742bcd0..d933ef1 100644 (file)
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -768,6 +768,7 @@ void
 v9fs_stat2inode(struct v9fs_stat *stat, struct inode *inode,
        struct super_block *sb)
 {
+       int n;
        char ext[32];
        struct v9fs_session_info *v9ses = sb->s_fs_info;
 
@@ -791,7 +792,11 @@ v9fs_stat2inode(struct v9fs_stat *stat, struct inode *inode,
                int major = -1;
                int minor = -1;
 
-               v9fs_str_copy(ext, sizeof(ext), &stat->extension);
+               n = stat->extension.len;
+               if (n > sizeof(ext)-1)
+                       n = sizeof(ext)-1;
+               memmove(ext, stat->extension.str, n);
+               ext[n] = 0;
                sscanf(ext, "%c %u %u", &type, &major, &minor);
                switch (type) {
                case 'c':

diff --git a/fs/9p/vfs_super.c b/fs/9p/vfs_super.c
index d4d71a9..ae0f06b 100644 (file)
--- a/fs/9p/vfs_super.c
+++ b/fs/9p/vfs_super.c
@@ -122,11 +122,10 @@ static struct super_block *v9fs_get_sb(struct file_system_type
 
        dprintk(DEBUG_VFS, " \n");
 
-       v9ses = kmalloc(sizeof(struct v9fs_session_info), GFP_KERNEL);
+       v9ses = kzalloc(sizeof(struct v9fs_session_info), GFP_KERNEL);
        if (!v9ses)
                return ERR_PTR(-ENOMEM);
 
-       memset(v9ses, 0, sizeof(struct v9fs_session_info));
        if ((newfid = v9fs_session_init(v9ses, dev_name, data)) < 0) {
                dprintk(DEBUG_ERROR, "problem initiating session\n");
                kfree(v9ses);