ext4: fix SEEK_HOLE/SEEK_DATA for blocksize < pagesize

[sfrench/cifs-2.6.git] / fs / ext4 / file.c

diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 02ce7e7bbdf5ba4da0db50e50d8d4cab49cde4a3..0d7cf0cc9b87562bbc52b17224794d9147208910 100644 (file)
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -37,7 +37,11 @@ static ssize_t ext4_dax_read_iter(struct kiocb *iocb, struct iov_iter *to)
        struct inode *inode = file_inode(iocb->ki_filp);
        ssize_t ret;
 
-       inode_lock_shared(inode);
+       if (!inode_trylock_shared(inode)) {
+               if (iocb->ki_flags & IOCB_NOWAIT)
+                       return -EAGAIN;
+               inode_lock_shared(inode);
+       }
        /*
         * Recheck under inode lock - at this point we are sure it cannot
         * change anymore
@@ -179,7 +183,11 @@ ext4_dax_write_iter(struct kiocb *iocb, struct iov_iter *from)
        struct inode *inode = file_inode(iocb->ki_filp);
        ssize_t ret;
 
-       inode_lock(inode);
+       if (!inode_trylock(inode)) {
+               if (iocb->ki_flags & IOCB_NOWAIT)
+                       return -EAGAIN;
+               inode_lock(inode);
+       }
        ret = ext4_write_checks(iocb, from);
        if (ret <= 0)
                goto out;
@@ -216,7 +224,12 @@ ext4_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
                return ext4_dax_write_iter(iocb, from);
 #endif
 
-       inode_lock(inode);
+       if (!inode_trylock(inode)) {
+               if (iocb->ki_flags & IOCB_NOWAIT)
+                       return -EAGAIN;
+               inode_lock(inode);
+       }
+
        ret = ext4_write_checks(iocb, from);
        if (ret <= 0)
                goto out;
@@ -235,9 +248,15 @@ ext4_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
 
        iocb->private = &overwrite;
        /* Check whether we do a DIO overwrite or not */
-       if (o_direct && ext4_should_dioread_nolock(inode) && !unaligned_aio &&
-           ext4_overwrite_io(inode, iocb->ki_pos, iov_iter_count(from)))
-               overwrite = 1;
+       if (o_direct && !unaligned_aio) {
+               if (ext4_overwrite_io(inode, iocb->ki_pos, iov_iter_count(from))) {
+                       if (ext4_should_dioread_nolock(inode))
+                               overwrite = 1;
+               } else if (iocb->ki_flags & IOCB_NOWAIT) {
+                       ret = -EAGAIN;
+                       goto out;
+               }
+       }
 
        ret = __generic_file_write_iter(iocb, from);
        inode_unlock(inode);
@@ -345,13 +364,6 @@ static int ext4_file_mmap(struct file *file, struct vm_area_struct *vma)
        if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
                return -EIO;
 
-       if (ext4_encrypted_inode(inode)) {
-               int err = fscrypt_get_encryption_info(inode);
-               if (err)
-                       return 0;
-               if (!fscrypt_has_encryption_key(inode))
-                       return -ENOKEY;
-       }
        file_accessed(file);
        if (IS_DAX(file_inode(file))) {
                vma->vm_ops = &ext4_dax_vm_ops;
@@ -435,6 +447,10 @@ static int ext4_file_open(struct inode * inode, struct file * filp)
                if (ret < 0)
                        return ret;
        }
+
+       /* Set the flags to support nowait AIO */
+       filp->f_mode |= FMODE_AIO_NOWAIT;
+
        return dquot_file_open(inode, filp);
 }
 
@@ -521,6 +537,8 @@ static int ext4_find_unwritten_pgoff(struct inode *inode,
                                lastoff = page_offset(page);
                                bh = head = page_buffers(page);
                                do {
+                                       if (lastoff + bh->b_size <= startoff)
+                                               goto next;
                                        if (buffer_uptodate(bh) ||
                                            buffer_unwritten(bh)) {
                                                if (whence == SEEK_DATA)
@@ -535,6 +553,7 @@ static int ext4_find_unwritten_pgoff(struct inode *inode,
                                                unlock_page(page);
                                                goto out;
                                        }
+next:
                                        lastoff += bh->b_size;
                                        bh = bh->b_this_page;
                                } while (bh != head);