]> git.karo-electronics.de Git - karo-tx-linux.git/blobdiff - fs/ext4/file.c
Merge remote-tracking branch 'thermal-soc/next'
[karo-tx-linux.git] / fs / ext4 / file.c
index 113837e7ba98d5cf866ee365a40a89d7fc781a71..474f1a4d2ca8f45be1c0c97ce8c13a90cf75d34d 100644 (file)
@@ -113,7 +113,7 @@ ext4_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
                ext4_unwritten_wait(inode);
        }
 
-       mutex_lock(&inode->i_mutex);
+       inode_lock(inode);
        ret = generic_write_checks(iocb, from);
        if (ret <= 0)
                goto out;
@@ -169,7 +169,7 @@ ext4_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
        }
 
        ret = __generic_file_write_iter(iocb, from);
-       mutex_unlock(&inode->i_mutex);
+       inode_unlock(inode);
 
        if (ret > 0) {
                ssize_t err;
@@ -186,50 +186,42 @@ ext4_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
        return ret;
 
 out:
-       mutex_unlock(&inode->i_mutex);
+       inode_unlock(inode);
        if (aio_mutex)
                mutex_unlock(aio_mutex);
        return ret;
 }
 
 #ifdef CONFIG_FS_DAX
-static void ext4_end_io_unwritten(struct buffer_head *bh, int uptodate)
-{
-       struct inode *inode = bh->b_assoc_map->host;
-       /* XXX: breaks on 32-bit > 16TB. Is that even supported? */
-       loff_t offset = (loff_t)(uintptr_t)bh->b_private << inode->i_blkbits;
-       int err;
-       if (!uptodate)
-               return;
-       WARN_ON(!buffer_unwritten(bh));
-       err = ext4_convert_unwritten_extents(NULL, inode, offset, bh->b_size);
-}
-
 static int ext4_dax_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 {
        int result;
        handle_t *handle = NULL;
-       struct super_block *sb = file_inode(vma->vm_file)->i_sb;
+       struct inode *inode = file_inode(vma->vm_file);
+       struct super_block *sb = inode->i_sb;
        bool write = vmf->flags & FAULT_FLAG_WRITE;
 
        if (write) {
                sb_start_pagefault(sb);
                file_update_time(vma->vm_file);
+               down_read(&EXT4_I(inode)->i_mmap_sem);
                handle = ext4_journal_start_sb(sb, EXT4_HT_WRITE_PAGE,
                                                EXT4_DATA_TRANS_BLOCKS(sb));
-       }
+       } else
+               down_read(&EXT4_I(inode)->i_mmap_sem);
 
        if (IS_ERR(handle))
                result = VM_FAULT_SIGBUS;
        else
-               result = __dax_fault(vma, vmf, ext4_get_block_dax,
-                                               ext4_end_io_unwritten);
+               result = __dax_fault(vma, vmf, ext4_dax_mmap_get_block, NULL);
 
        if (write) {
                if (!IS_ERR(handle))
                        ext4_journal_stop(handle);
+               up_read(&EXT4_I(inode)->i_mmap_sem);
                sb_end_pagefault(sb);
-       }
+       } else
+               up_read(&EXT4_I(inode)->i_mmap_sem);
 
        return result;
 }
@@ -246,44 +238,88 @@ static int ext4_dax_pmd_fault(struct vm_area_struct *vma, unsigned long addr,
        if (write) {
                sb_start_pagefault(sb);
                file_update_time(vma->vm_file);
+               down_read(&EXT4_I(inode)->i_mmap_sem);
                handle = ext4_journal_start_sb(sb, EXT4_HT_WRITE_PAGE,
                                ext4_chunk_trans_blocks(inode,
                                                        PMD_SIZE / PAGE_SIZE));
-       }
+       } else
+               down_read(&EXT4_I(inode)->i_mmap_sem);
 
        if (IS_ERR(handle))
                result = VM_FAULT_SIGBUS;
        else
                result = __dax_pmd_fault(vma, addr, pmd, flags,
-                               ext4_get_block_dax, ext4_end_io_unwritten);
+                               ext4_dax_mmap_get_block, NULL);
 
        if (write) {
                if (!IS_ERR(handle))
                        ext4_journal_stop(handle);
+               up_read(&EXT4_I(inode)->i_mmap_sem);
                sb_end_pagefault(sb);
-       }
+       } else
+               up_read(&EXT4_I(inode)->i_mmap_sem);
 
        return result;
 }
 
 static int ext4_dax_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
 {
-       return dax_mkwrite(vma, vmf, ext4_get_block_dax,
-                               ext4_end_io_unwritten);
+       int err;
+       struct inode *inode = file_inode(vma->vm_file);
+
+       sb_start_pagefault(inode->i_sb);
+       file_update_time(vma->vm_file);
+       down_read(&EXT4_I(inode)->i_mmap_sem);
+       err = __dax_mkwrite(vma, vmf, ext4_dax_mmap_get_block, NULL);
+       up_read(&EXT4_I(inode)->i_mmap_sem);
+       sb_end_pagefault(inode->i_sb);
+
+       return err;
+}
+
+/*
+ * Handle write fault for VM_MIXEDMAP mappings. Similarly to ext4_dax_mkwrite()
+ * handler we check for races agaist truncate. Note that since we cycle through
+ * i_mmap_sem, we are sure that also any hole punching that began before we
+ * were called is finished by now and so if it included part of the file we
+ * are working on, our pte will get unmapped and the check for pte_same() in
+ * wp_pfn_shared() fails. Thus fault gets retried and things work out as
+ * desired.
+ */
+static int ext4_dax_pfn_mkwrite(struct vm_area_struct *vma,
+                               struct vm_fault *vmf)
+{
+       struct inode *inode = file_inode(vma->vm_file);
+       struct super_block *sb = inode->i_sb;
+       loff_t size;
+       int ret;
+
+       sb_start_pagefault(sb);
+       file_update_time(vma->vm_file);
+       down_read(&EXT4_I(inode)->i_mmap_sem);
+       size = (i_size_read(inode) + PAGE_SIZE - 1) >> PAGE_SHIFT;
+       if (vmf->pgoff >= size)
+               ret = VM_FAULT_SIGBUS;
+       else
+               ret = dax_pfn_mkwrite(vma, vmf);
+       up_read(&EXT4_I(inode)->i_mmap_sem);
+       sb_end_pagefault(sb);
+
+       return ret;
 }
 
 static const struct vm_operations_struct ext4_dax_vm_ops = {
        .fault          = ext4_dax_fault,
        .pmd_fault      = ext4_dax_pmd_fault,
        .page_mkwrite   = ext4_dax_mkwrite,
-       .pfn_mkwrite    = dax_pfn_mkwrite,
+       .pfn_mkwrite    = ext4_dax_pfn_mkwrite,
 };
 #else
 #define ext4_dax_vm_ops        ext4_file_vm_ops
 #endif
 
 static const struct vm_operations_struct ext4_file_vm_ops = {
-       .fault          = filemap_fault,
+       .fault          = ext4_filemap_fault,
        .map_pages      = filemap_map_pages,
        .page_mkwrite   = ext4_page_mkwrite,
 };
@@ -314,6 +350,7 @@ static int ext4_file_open(struct inode * inode, struct file * filp)
        struct super_block *sb = inode->i_sb;
        struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
        struct vfsmount *mnt = filp->f_path.mnt;
+       struct inode *dir = filp->f_path.dentry->d_parent->d_inode;
        struct path path;
        char buf[64], *cp;
        int ret;
@@ -357,6 +394,14 @@ static int ext4_file_open(struct inode * inode, struct file * filp)
                if (ext4_encryption_info(inode) == NULL)
                        return -ENOKEY;
        }
+       if (ext4_encrypted_inode(dir) &&
+           !ext4_is_child_context_consistent_with_parent(dir, inode)) {
+               ext4_warning(inode->i_sb,
+                            "Inconsistent encryption contexts: %lu/%lu\n",
+                            (unsigned long) dir->i_ino,
+                            (unsigned long) inode->i_ino);
+               return -EPERM;
+       }
        /*
         * Set up the jbd2_inode if we are opening the inode for
         * writing and the journal is present
@@ -527,11 +572,11 @@ static loff_t ext4_seek_data(struct file *file, loff_t offset, loff_t maxsize)
        int blkbits;
        int ret = 0;
 
-       mutex_lock(&inode->i_mutex);
+       inode_lock(inode);
 
        isize = i_size_read(inode);
        if (offset >= isize) {
-               mutex_unlock(&inode->i_mutex);
+               inode_unlock(inode);
                return -ENXIO;
        }
 
@@ -579,7 +624,7 @@ static loff_t ext4_seek_data(struct file *file, loff_t offset, loff_t maxsize)
                dataoff = (loff_t)last << blkbits;
        } while (last <= end);
 
-       mutex_unlock(&inode->i_mutex);
+       inode_unlock(inode);
 
        if (dataoff > isize)
                return -ENXIO;
@@ -600,11 +645,11 @@ static loff_t ext4_seek_hole(struct file *file, loff_t offset, loff_t maxsize)
        int blkbits;
        int ret = 0;
 
-       mutex_lock(&inode->i_mutex);
+       inode_lock(inode);
 
        isize = i_size_read(inode);
        if (offset >= isize) {
-               mutex_unlock(&inode->i_mutex);
+               inode_unlock(inode);
                return -ENXIO;
        }
 
@@ -655,7 +700,7 @@ static loff_t ext4_seek_hole(struct file *file, loff_t offset, loff_t maxsize)
                break;
        } while (last <= end);
 
-       mutex_unlock(&inode->i_mutex);
+       inode_unlock(inode);
 
        if (holeoff > isize)
                holeoff = isize;