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-rw-r--r--fs/afs/inode.c47
-rw-r--r--fs/afs/internal.h1
-rw-r--r--fs/afs/write.c11
3 files changed, 50 insertions, 9 deletions
diff --git a/fs/afs/inode.c b/fs/afs/inode.c
index 1d13d2e882ad..0fe8844b4bee 100644
--- a/fs/afs/inode.c
+++ b/fs/afs/inode.c
@@ -810,14 +810,32 @@ void afs_evict_inode(struct inode *inode)
static void afs_setattr_success(struct afs_operation *op)
{
- struct inode *inode = &op->file[0].vnode->vfs_inode;
+ struct afs_vnode_param *vp = &op->file[0];
+ struct inode *inode = &vp->vnode->vfs_inode;
+ loff_t old_i_size = i_size_read(inode);
+
+ op->setattr.old_i_size = old_i_size;
+ afs_vnode_commit_status(op, vp);
+ /* inode->i_size has now been changed. */
+
+ if (op->setattr.attr->ia_valid & ATTR_SIZE) {
+ loff_t size = op->setattr.attr->ia_size;
+ if (size > old_i_size)
+ pagecache_isize_extended(inode, old_i_size, size);
+ }
+}
+
+static void afs_setattr_edit_file(struct afs_operation *op)
+{
+ struct afs_vnode_param *vp = &op->file[0];
+ struct inode *inode = &vp->vnode->vfs_inode;
- afs_vnode_commit_status(op, &op->file[0]);
if (op->setattr.attr->ia_valid & ATTR_SIZE) {
- loff_t i_size = inode->i_size, size = op->setattr.attr->ia_size;
- if (size > i_size)
- pagecache_isize_extended(inode, i_size, size);
- truncate_pagecache(inode, size);
+ loff_t size = op->setattr.attr->ia_size;
+ loff_t i_size = op->setattr.old_i_size;
+
+ if (size < i_size)
+ truncate_pagecache(inode, size);
}
}
@@ -825,6 +843,7 @@ static const struct afs_operation_ops afs_setattr_operation = {
.issue_afs_rpc = afs_fs_setattr,
.issue_yfs_rpc = yfs_fs_setattr,
.success = afs_setattr_success,
+ .edit_dir = afs_setattr_edit_file,
};
/*
@@ -863,11 +882,16 @@ int afs_setattr(struct dentry *dentry, struct iattr *attr)
if (S_ISREG(vnode->vfs_inode.i_mode))
filemap_write_and_wait(vnode->vfs_inode.i_mapping);
+ /* Prevent any new writebacks from starting whilst we do this. */
+ down_write(&vnode->validate_lock);
+
op = afs_alloc_operation(((attr->ia_valid & ATTR_FILE) ?
afs_file_key(attr->ia_file) : NULL),
vnode->volume);
- if (IS_ERR(op))
- return PTR_ERR(op);
+ if (IS_ERR(op)) {
+ ret = PTR_ERR(op);
+ goto out_unlock;
+ }
afs_op_set_vnode(op, 0, vnode);
op->setattr.attr = attr;
@@ -880,5 +904,10 @@ int afs_setattr(struct dentry *dentry, struct iattr *attr)
op->file[0].update_ctime = 1;
op->ops = &afs_setattr_operation;
- return afs_do_sync_operation(op);
+ ret = afs_do_sync_operation(op);
+
+out_unlock:
+ up_write(&vnode->validate_lock);
+ _leave(" = %d", ret);
+ return ret;
}
diff --git a/fs/afs/internal.h b/fs/afs/internal.h
index 18042b7dab6a..e5f0446f27e5 100644
--- a/fs/afs/internal.h
+++ b/fs/afs/internal.h
@@ -812,6 +812,7 @@ struct afs_operation {
} store;
struct {
struct iattr *attr;
+ loff_t old_i_size;
} setattr;
struct afs_acl *acl;
struct yfs_acl *yacl;
diff --git a/fs/afs/write.c b/fs/afs/write.c
index 4b2265cb1891..da12abd6db21 100644
--- a/fs/afs/write.c
+++ b/fs/afs/write.c
@@ -738,11 +738,21 @@ static int afs_writepages_region(struct address_space *mapping,
int afs_writepages(struct address_space *mapping,
struct writeback_control *wbc)
{
+ struct afs_vnode *vnode = AFS_FS_I(mapping->host);
pgoff_t start, end, next;
int ret;
_enter("");
+ /* We have to be careful as we can end up racing with setattr()
+ * truncating the pagecache since the caller doesn't take a lock here
+ * to prevent it.
+ */
+ if (wbc->sync_mode == WB_SYNC_ALL)
+ down_read(&vnode->validate_lock);
+ else if (!down_read_trylock(&vnode->validate_lock))
+ return 0;
+
if (wbc->range_cyclic) {
start = mapping->writeback_index;
end = -1;
@@ -762,6 +772,7 @@ int afs_writepages(struct address_space *mapping,
ret = afs_writepages_region(mapping, wbc, start, end, &next);
}
+ up_read(&vnode->validate_lock);
_leave(" = %d", ret);
return ret;
}