From: gaoyongliang <gaoyongliang@xxxxxxxxxx>
1. create inode by insert_inode_locked, and return inode with I_NEW.
2. has writed the dnode successfully in the end of one block, then
release the c->alloc_sem, but the dirent is not written yet.
3. the gc or jffs2_reserve_space which has got the c->alloc_sem may
find the block which the dnode we just writed in, the dnode can't
be gc because the dirent is not written and the state of inode is
still I_NEW, we can only wait on inode without release c->alloc_sem.
4. we can't get the c->alloc_sem to write the dirent, so the inode
state keep I_NEW forever.
5. this will cause deadlock, like ABBA deadlock.
lockf2.test D c02dead8 0 11666 1 0x00000001
locked:
c90f9be8 &inode->i_mutex 0 [<c00bf158>] generic_file_aio_write+0x40/0xb0
c2c54c44 &c->alloc_sem 1 [<bf056f9c>] jffs2_garbage_collect_pass+0x1c/0xf08 [jffs2]
[<c02dead8>] (__schedule+0x458/0x604) from [<c0114090>] (inode_wait+0x8/0x10)
[<c0114090>] (inode_wait+0x8/0x10) from [<c02dd050>] (__wait_on_bit+0x54/0xa0)
[<c02dd050>] (__wait_on_bit+0x54/0xa0) from [<c02dd114>] (out_of_line_wait_on_bit+0x78/0x84)
[<c02dd114>] (out_of_line_wait_on_bit+0x78/0x84) from [<c01157a0>] (iget_locked+0x90/0x1b0)
[<c01157a0>] (iget_locked+0x90/0x1b0) from [<bf059fe8>] (jffs2_iget+0xc/0x344 [jffs2])
[<bf059fe8>] (jffs2_iget+0xc/0x344 [jffs2]) from [<bf05a6fc>] (jffs2_gc_fetch_inode+0x104/0x158 [jffs2])
[<bf05a6fc>] (jffs2_gc_fetch_inode+0x104/0x158 [jffs2]) from [<bf0577f0>] (jffs2_garbage_collect_pass+0x870/0xf08 [jffs2])
[<bf0577f0>] (jffs2_garbage_collect_pass+0x870/0xf08 [jffs2]) from [<bf051248>] (jffs2_reserve_space+0x154/0x3b4 [jffs2])
[<bf051248>] (jffs2_reserve_space+0x154/0x3b4 [jffs2]) from [<bf053eac>] (jffs2_write_inode_range+0x58/0x3ac [jffs2])
[<bf053eac>] (jffs2_write_inode_range+0x58/0x3ac [jffs2]) from [<bf04ec20>] (jffs2_write_end+0x11c/0x224 [jffs2])
[<bf04ec20>] (jffs2_write_end+0x11c/0x224 [jffs2]) from [<c00bdfa4>] (generic_file_buffered_write+0x160/0x23c)
[<c00bdfa4>] (generic_file_buffered_write+0x160/0x23c) from [<c00bf0ac>] (__generic_file_aio_write+0x328/0x394)
[<c00bf0ac>] (__generic_file_aio_write+0x328/0x394) from [<c00bf16c>] (generic_file_aio_write+0x54/0xb0)
[<c00bf16c>] (generic_file_aio_write+0x54/0xb0) from [<c00fdc24>] (do_sync_write+0x74/0x98)
[<c00fdc24>] (do_sync_write+0x74/0x98) from [<c00fe550>] (vfs_write+0xcc/0x174)
[<c00fe550>] (vfs_write+0xcc/0x174) from [<c00fe8a8>] (SyS_write+0x38/0x64)
[<c00fe8a8>] (SyS_write+0x38/0x64) from [<c000f0c0>] (ret_fast_syscall+0x0/0x58)
Fixes: e72e6497e74811e01d72b4c1b7537b3aea3ee857
Cc: <stable@xxxxxxxxxxxxxxx> # 3.10.y+
Signed-off-by: gaoyongliang <gaoyongliang@xxxxxxxxxx>
---
fs/jffs2/dir.c | 25 +++++++++++++++++++++++++
fs/jffs2/fs.c | 1 +
fs/jffs2/gc.c | 11 +++++++++++
fs/jffs2/jffs2_fs_sb.h | 1 +
fs/jffs2/nodelist.h | 4 ++++
fs/jffs2/super.c | 1 +
fs/jffs2/write.c | 1 +
7 files changed, 44 insertions(+), 0 deletions(-)
diff --git a/fs/jffs2/dir.c b/fs/jffs2/dir.c
index d211b8e..808ec17 100644
--- a/fs/jffs2/dir.c
+++ b/fs/jffs2/dir.c
@@ -195,7 +195,9 @@ static int jffs2_create(struct inode *dir_i, struct dentry *dentry,
no chance of AB-BA deadlock involving its f->sem). */
mutex_unlock(&f->sem);
+ mutex_lock(&c->create_sem);
ret = jffs2_do_create(c, dir_f, f, ri, &dentry->d_name);
+ mutex_unlock(&c->create_sem);
if (ret)
goto fail;
@@ -208,12 +210,14 @@ static int jffs2_create(struct inode *dir_i, struct dentry *dentry,
f->inocache->pino_nlink, inode->i_mapping->nrpages);
unlock_new_inode(inode);
+ f->inocache->state_new = INO_STATE_N_NEW;
d_instantiate(dentry, inode);
return 0;
fail:
iget_failed(inode);
jffs2_free_raw_inode(ri);
+ f->inocache->state_new = INO_STATE_N_NEW;
return ret;
}
@@ -304,11 +308,13 @@ static int jffs2_symlink (struct inode *dir_i, struct dentry *dentry, const char
* Just the node will do for now, though
*/
namelen = dentry->d_name.len;
+ mutex_lock(&c->create_sem);
ret = jffs2_reserve_space(c, sizeof(*ri) + targetlen, &alloclen,
ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
if (ret) {
jffs2_free_raw_inode(ri);
+ mutex_unlock(&c->create_sem);
return ret;
}
@@ -317,6 +323,7 @@ static int jffs2_symlink (struct inode *dir_i, struct dentry *dentry, const char
if (IS_ERR(inode)) {
jffs2_free_raw_inode(ri);
jffs2_complete_reservation(c);
+ mutex_unlock(&c->create_sem);
return PTR_ERR(inode);
}
@@ -429,11 +436,15 @@ static int jffs2_symlink (struct inode *dir_i, struct dentry *dentry, const char
jffs2_complete_reservation(c);
unlock_new_inode(inode);
+ f->inocache->state_new = INO_STATE_N_NEW;
+ mutex_unlock(&c->create_sem);
d_instantiate(dentry, inode);
return 0;
fail:
iget_failed(inode);
+ f->inocache->state_new = INO_STATE_N_NEW;
+ mutex_unlock(&c->create_sem);
return ret;
}
@@ -463,11 +474,13 @@ static int jffs2_mkdir (struct inode *dir_i, struct dentry *dentry, umode_t mode
* Just the node will do for now, though
*/
namelen = dentry->d_name.len;
+ mutex_lock(&c->create_sem);
ret = jffs2_reserve_space(c, sizeof(*ri), &alloclen, ALLOC_NORMAL,
JFFS2_SUMMARY_INODE_SIZE);
if (ret) {
jffs2_free_raw_inode(ri);
+ mutex_unlock(&c->create_sem);
return ret;
}
@@ -476,6 +489,7 @@ static int jffs2_mkdir (struct inode *dir_i, struct dentry *dentry, umode_t mode
if (IS_ERR(inode)) {
jffs2_free_raw_inode(ri);
jffs2_complete_reservation(c);
+ mutex_unlock(&c->create_sem);
return PTR_ERR(inode);
}
@@ -574,11 +588,15 @@ static int jffs2_mkdir (struct inode *dir_i, struct dentry *dentry, umode_t mode
jffs2_complete_reservation(c);
unlock_new_inode(inode);
+ f->inocache->state_new = INO_STATE_N_NEW;
+ mutex_unlock(&c->create_sem);
d_instantiate(dentry, inode);
return 0;
fail:
iget_failed(inode);
+ f->inocache->state_new = INO_STATE_N_NEW;
+ mutex_unlock(&c->create_sem);
return ret;
}
@@ -634,11 +652,13 @@ static int jffs2_mknod (struct inode *dir_i, struct dentry *dentry, umode_t mode
* Just the node will do for now, though
*/
namelen = dentry->d_name.len;
+ mutex_lock(&c->create_sem);
ret = jffs2_reserve_space(c, sizeof(*ri) + devlen, &alloclen,
ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
if (ret) {
jffs2_free_raw_inode(ri);
+ mutex_unlock(&c->create_sem);
return ret;
}
@@ -647,6 +667,7 @@ static int jffs2_mknod (struct inode *dir_i, struct dentry *dentry, umode_t mode
if (IS_ERR(inode)) {
jffs2_free_raw_inode(ri);
jffs2_complete_reservation(c);
+ mutex_unlock(&c->create_sem);
return PTR_ERR(inode);
}
inode->i_op = &jffs2_file_inode_operations;
@@ -746,11 +767,15 @@ static int jffs2_mknod (struct inode *dir_i, struct dentry *dentry, umode_t mode
jffs2_complete_reservation(c);
unlock_new_inode(inode);
+ f->inocache->state_new = INO_STATE_N_NEW;
+ mutex_unlock(&c->create_sem);
d_instantiate(dentry, inode);
return 0;
fail:
iget_failed(inode);
+ f->inocache->state_new = INO_STATE_N_NEW;
+ mutex_unlock(&c->create_sem);
return ret;
}
diff --git a/fs/jffs2/fs.c b/fs/jffs2/fs.c
index 2caf168..c98fd3c 100644
--- a/fs/jffs2/fs.c
+++ b/fs/jffs2/fs.c
@@ -482,6 +482,7 @@ struct inode *jffs2_new_inode (struct inode *dir_i, umode_t mode, struct jffs2_r
mutex_unlock(&f->sem);
make_bad_inode(inode);
iput(inode);
+ f->inocache->state_new = INO_STATE_N_NEW;
return ERR_PTR(-EINVAL);
}
diff --git a/fs/jffs2/gc.c b/fs/jffs2/gc.c
index 5a2dec2..51f2a4b 100644
--- a/fs/jffs2/gc.c
+++ b/fs/jffs2/gc.c
@@ -333,6 +333,17 @@ int jffs2_garbage_collect_pass(struct jffs2_sb_info *c)
__func__, jeb->offset, ref_offset(raw), ref_flags(raw),
ic->ino);
+ /* create but not finished so find next block */
+ if (ic->state_new == INO_STATE_I_NEW) {
+ jffs2_dbg(1, "%s(): ino #%u in state new so find next block\n",
+ __func__, ic->ino);
+ c->gcblock = NULL;
+ list_add_tail(&jeb->list, &c->dirty_list);
+ mutex_unlock(&c->alloc_sem);
+ spin_unlock(&c->inocache_lock);
+ return 0;
+ }
+
/* Three possibilities:
1. Inode is already in-core. We must iget it and do proper
updating to its fragtree, etc.
diff --git a/fs/jffs2/jffs2_fs_sb.h b/fs/jffs2/jffs2_fs_sb.h
index 046fee8..32193b7 100644
--- a/fs/jffs2/jffs2_fs_sb.h
+++ b/fs/jffs2/jffs2_fs_sb.h
@@ -57,6 +57,7 @@ struct jffs2_sb_info {
struct completion gc_thread_start; /* GC thread start completion */
struct completion gc_thread_exit; /* GC thread exit completion port */
+ struct mutex create_sem; /* Used to protect write dnode and dirent in order */
struct mutex alloc_sem; /* Used to protect all the following
fields, and also to protect against
out-of-order writing of nodes. And GC. */
diff --git a/fs/jffs2/nodelist.h b/fs/jffs2/nodelist.h
index fa35ff7..ec377e0 100644
--- a/fs/jffs2/nodelist.h
+++ b/fs/jffs2/nodelist.h
@@ -180,6 +180,7 @@ struct jffs2_inode_cache {
here; other inodes store nlink.
Zero always means that it's
completely unlinked. */
+ uint32_t state_new; /* create flag */
};
/* Inode states for 'state' above. We need the 'GC' state to prevent
@@ -193,6 +194,9 @@ struct jffs2_inode_cache {
#define INO_STATE_READING 5 /* In read_inode() */
#define INO_STATE_CLEARING 6 /* In clear_inode() */
+#define INO_STATE_N_NEW 0 /* Finish to create */
+#define INO_STATE_I_NEW 1 /* Just create but not finish */
+
#define INO_FLAGS_XATTR_CHECKED 0x01 /* has no duplicate xattr_ref */
#define RAWNODE_CLASS_INODE_CACHE 0
diff --git a/fs/jffs2/super.c b/fs/jffs2/super.c
index d86c5e3..99c5715 100644
--- a/fs/jffs2/super.c
+++ b/fs/jffs2/super.c
@@ -292,6 +292,7 @@ static int jffs2_fill_super(struct super_block *sb, void *data, int silent)
/* Initialize JFFS2 superblock locks, the further initialization will
* be done later */
+ mutex_init(&c->create_sem);
mutex_init(&c->alloc_sem);
mutex_init(&c->erase_free_sem);
init_waitqueue_head(&c->erase_wait);
diff --git a/fs/jffs2/write.c b/fs/jffs2/write.c
index b634de4..dc8242d 100644
--- a/fs/jffs2/write.c
+++ b/fs/jffs2/write.c
@@ -36,6 +36,7 @@ int jffs2_do_new_inode(struct jffs2_sb_info *c, struct jffs2_inode_info *f,
f->inocache->pino_nlink = 1; /* Will be overwritten shortly for directories */
f->inocache->nodes = (struct jffs2_raw_node_ref *)f->inocache;
f->inocache->state = INO_STATE_PRESENT;
+ f->inocache->state_new = INO_STATE_I_NEW;
jffs2_add_ino_cache(c, f->inocache);
jffs2_dbg(1, "%s(): Assigned ino# %d\n", __func__, f->inocache->ino);
--
1.7.6
--
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