Merge drm/drm-fixes into drm-misc-fixes

Backmerging drm/drm-fixes for commit 3755d35ee1d2 ("drm/panel: Select
DRM_DP_HELPER for DRM_PANEL_EDP").

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

3 files changed, 80 insertions, 4 deletions

diff --git a/fs/cachefiles/interface.c b/fs/cachefiles/interface.c
index 51c968cd00a6..ae93cee9d25d 100644
--- a/fs/cachefiles/interface.c
+++ b/fs/cachefiles/interface.c
@@ -254,7 +254,7 @@ static bool cachefiles_shorten_object(struct cachefiles_object *object,
 		ret = cachefiles_inject_write_error();
 		if (ret == 0)
 			ret = vfs_fallocate(file, FALLOC_FL_ZERO_RANGE,
-					    new_size, dio_size);
+					    new_size, dio_size - new_size);
 		if (ret < 0) {
 			trace_cachefiles_io_error(object, file_inode(file), ret,
 						  cachefiles_trace_fallocate_error);
diff --git a/fs/cachefiles/io.c b/fs/cachefiles/io.c
index 04eb52736990..753986ea1583 100644
--- a/fs/cachefiles/io.c
+++ b/fs/cachefiles/io.c
@@ -192,6 +192,64 @@ presubmission_error:
 }
 
 /*
+ * Query the occupancy of the cache in a region, returning where the next chunk
+ * of data starts and how long it is.
+ */
+static int cachefiles_query_occupancy(struct netfs_cache_resources *cres,
+				      loff_t start, size_t len, size_t granularity,
+				      loff_t *_data_start, size_t *_data_len)
+{
+	struct cachefiles_object *object;
+	struct file *file;
+	loff_t off, off2;
+
+	*_data_start = -1;
+	*_data_len = 0;
+
+	if (!fscache_wait_for_operation(cres, FSCACHE_WANT_READ))
+		return -ENOBUFS;
+
+	object = cachefiles_cres_object(cres);
+	file = cachefiles_cres_file(cres);
+	granularity = max_t(size_t, object->volume->cache->bsize, granularity);
+
+	_enter("%pD,%li,%llx,%zx/%llx",
+	       file, file_inode(file)->i_ino, start, len,
+	       i_size_read(file_inode(file)));
+
+	off = cachefiles_inject_read_error();
+	if (off == 0)
+		off = vfs_llseek(file, start, SEEK_DATA);
+	if (off == -ENXIO)
+		return -ENODATA; /* Beyond EOF */
+	if (off < 0 && off >= (loff_t)-MAX_ERRNO)
+		return -ENOBUFS; /* Error. */
+	if (round_up(off, granularity) >= start + len)
+		return -ENODATA; /* No data in range */
+
+	off2 = cachefiles_inject_read_error();
+	if (off2 == 0)
+		off2 = vfs_llseek(file, off, SEEK_HOLE);
+	if (off2 == -ENXIO)
+		return -ENODATA; /* Beyond EOF */
+	if (off2 < 0 && off2 >= (loff_t)-MAX_ERRNO)
+		return -ENOBUFS; /* Error. */
+
+	/* Round away partial blocks */
+	off = round_up(off, granularity);
+	off2 = round_down(off2, granularity);
+	if (off2 <= off)
+		return -ENODATA;
+
+	*_data_start = off;
+	if (off2 > start + len)
+		*_data_len = len;
+	else
+		*_data_len = off2 - off;
+	return 0;
+}
+
+/*
  * Handle completion of a write to the cache.
  */
 static void cachefiles_write_complete(struct kiocb *iocb, long ret)
@@ -545,6 +603,7 @@ static const struct netfs_cache_ops cachefiles_netfs_cache_ops = {
 	.write			= cachefiles_write,
 	.prepare_read		= cachefiles_prepare_read,
 	.prepare_write		= cachefiles_prepare_write,
+	.query_occupancy	= cachefiles_query_occupancy,
 };
 
 /*
diff --git a/fs/cachefiles/xattr.c b/fs/cachefiles/xattr.c
index 83f41bd0c3a9..35465109d9c4 100644
--- a/fs/cachefiles/xattr.c
+++ b/fs/cachefiles/xattr.c
@@ -28,6 +28,11 @@ struct cachefiles_xattr {
 static const char cachefiles_xattr_cache[] =
 	XATTR_USER_PREFIX "CacheFiles.cache";
 
+struct cachefiles_vol_xattr {
+	__be32	reserved;	/* Reserved, should be 0 */
+	__u8	data[];		/* netfs volume coherency data */
+} __packed;
+
 /*
  * set the state xattr on a cache file
  */
@@ -185,6 +190,7 @@ void cachefiles_prepare_to_write(struct fscache_cookie *cookie)
  */
 bool cachefiles_set_volume_xattr(struct cachefiles_volume *volume)
 {
+	struct cachefiles_vol_xattr *buf;
 	unsigned int len = volume->vcookie->coherency_len;
 	const void *p = volume->vcookie->coherency;
 	struct dentry *dentry = volume->dentry;
@@ -192,10 +198,17 @@ bool cachefiles_set_volume_xattr(struct cachefiles_volume *volume)
 
 	_enter("%x,#%d", volume->vcookie->debug_id, len);
 
+	len += sizeof(*buf);
+	buf = kmalloc(len, GFP_KERNEL);
+	if (!buf)
+		return false;
+	buf->reserved = cpu_to_be32(0);
+	memcpy(buf->data, p, len);
+
 	ret = cachefiles_inject_write_error();
 	if (ret == 0)
 		ret = vfs_setxattr(&init_user_ns, dentry, cachefiles_xattr_cache,
-				   p, len, 0);
+				   buf, len, 0);
 	if (ret < 0) {
 		trace_cachefiles_vfs_error(NULL, d_inode(dentry), ret,
 					   cachefiles_trace_setxattr_error);
@@ -209,6 +222,7 @@ bool cachefiles_set_volume_xattr(struct cachefiles_volume *volume)
 					       cachefiles_coherency_vol_set_ok);
 	}
 
+	kfree(buf);
 	_leave(" = %d", ret);
 	return ret == 0;
 }
@@ -218,7 +232,7 @@ bool cachefiles_set_volume_xattr(struct cachefiles_volume *volume)
  */
 int cachefiles_check_volume_xattr(struct cachefiles_volume *volume)
 {
-	struct cachefiles_xattr *buf;
+	struct cachefiles_vol_xattr *buf;
 	struct dentry *dentry = volume->dentry;
 	unsigned int len = volume->vcookie->coherency_len;
 	const void *p = volume->vcookie->coherency;
@@ -228,6 +242,7 @@ int cachefiles_check_volume_xattr(struct cachefiles_volume *volume)
 
 	_enter("");
 
+	len += sizeof(*buf);
 	buf = kmalloc(len, GFP_KERNEL);
 	if (!buf)
 		return -ENOMEM;
@@ -245,7 +260,9 @@ int cachefiles_check_volume_xattr(struct cachefiles_volume *volume)
 					"Failed to read xattr with error %zd", xlen);
 		}
 		why = cachefiles_coherency_vol_check_xattr;
-	} else if (memcmp(buf->data, p, len) != 0) {
+	} else if (buf->reserved != cpu_to_be32(0)) {
+		why = cachefiles_coherency_vol_check_resv;
+	} else if (memcmp(buf->data, p, len - sizeof(*buf)) != 0) {
 		why = cachefiles_coherency_vol_check_cmp;
 	} else {
 		why = cachefiles_coherency_vol_check_ok;