Merge tag 'nilfs2-v7.0-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/vdubeyko/nilfs2

Pull nilfs2 updates from Viacheslav Dubeyko:

 - Fix potential block overflow that cause system hang

   When executing the FITRIM command, an underflow can occur in the
   calculation of nblocks. This ultimately leads to the block layer
   function __blkdev_issue_discard() taking an excessively long time
   to process the bio chain, and the ns_segctor_sem lock remains held
   for a long period.

   This prevents other tasks from acquiring the ns_segctor_sem lock,
   resulting in a hang reported by syzbot (Edward Adam Davis)

 - Fix missing struct keywords in nilfs2_api.h kernel-doc (Ryusuke
   Konishi)

 - Convert nilfs_super_block to kernel-doc

   Eliminate 40+ kernel-doc warnings in nilfs2_ondisk.h by converting
   all of the struct member comments to kernel-doc comments (Randy
   Dunlap)

* tag 'nilfs2-v7.0-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/vdubeyko/nilfs2:
  nilfs2: fix missing struct keywords in nilfs2_api.h kernel-doc
  nilfs2: convert nilfs_super_block to kernel-doc
  nilfs2: Fix potential block overflow that cause system hang

Author: torvalds

fs/nilfs2/sufile.c

@@ -1093,6 +1093,9 @@ int nilfs_sufile_trim_fs(struct inode *sufile, struct fstrim_range *range)
 	else
 		end_block = start_block + len - 1;
 
+	if (end_block < nilfs->ns_first_data_block)
+		goto out;
+
 	segnum = nilfs_get_segnum_of_block(nilfs, start_block);
 	segnum_end = nilfs_get_segnum_of_block(nilfs, end_block);
 
@@ -1191,6 +1194,7 @@ int nilfs_sufile_trim_fs(struct inode *sufile, struct fstrim_range *range)
 out_sem:
 	up_read(&NILFS_MDT(sufile)->mi_sem);
 
+out:
 	range->len = ndiscarded << nilfs->ns_blocksize_bits;
 	return ret;
 }

include/uapi/linux/nilfs2_api.h

@@ -58,7 +58,7 @@ NILFS_CPINFO_FNS(INVALID, invalid)
 NILFS_CPINFO_FNS(MINOR, minor)
 
 /**
- * nilfs_suinfo - segment usage information
+ * struct nilfs_suinfo - segment usage information
  * @sui_lastmod: timestamp of last modification
  * @sui_nblocks: number of written blocks in segment
  * @sui_flags: segment usage flags
@@ -93,7 +93,7 @@ static inline int nilfs_suinfo_clean(const struct nilfs_suinfo *si)
 }
 
 /**
- * nilfs_suinfo_update - segment usage information update
+ * struct nilfs_suinfo_update - segment usage information update
  * @sup_segnum: segment number
  * @sup_flags: flags for which fields are active in sup_sui
  * @sup_reserved: reserved necessary for alignment

include/uapi/linux/nilfs2_ondisk.h

@@ -133,73 +133,104 @@ struct nilfs_super_root {
 
 /**
  * struct nilfs_super_block - structure of super block on disk
+ * @s_rev_level:		Revision level
+ * @s_minor_rev_level:		minor revision level
+ * @s_magic:			Magic signature
+ * @s_bytes:			Bytes count of CRC calculation for
+ *				  this structure.  s_reserved is excluded.
+ * @s_flags:			flags
+ * @s_crc_seed:			Seed value of CRC calculation
+ * @s_sum:			Check sum of super block
+ * @s_log_block_size:		Block size represented as follows:
+ *				  blocksize = 1 << (s_log_block_size + 10)
+ * @s_nsegments:		Number of segments in filesystem
+ * @s_dev_size:			block device size in bytes
+ * @s_first_data_block:		1st seg disk block number
+ * @s_blocks_per_segment:	number of blocks per full segment
+ * @s_r_segments_percentage:	Reserved segments percentage
+ * @s_last_cno:			Last checkpoint number
+ * @s_last_pseg:		disk block addr pseg written last
+ * @s_last_seq:			seq. number of seg written last
+ * @s_free_blocks_count:	Free blocks count
+ * @s_ctime:			Creation time (execution time of newfs)
+ * @s_mtime:			Mount time
+ * @s_wtime:			Write time
+ * @s_mnt_count:		Mount count
+ * @s_max_mnt_count:		Maximal mount count
+ * @s_state:			File system state
+ * @s_errors:			Behaviour when detecting errors
+ * @s_lastcheck:		time of last check
+ * @s_checkinterval:		max. time between checks
+ * @s_creator_os:		OS
+ * @s_def_resuid:		Default uid for reserved blocks
+ * @s_def_resgid:		Default gid for reserved blocks
+ * @s_first_ino:		First non-reserved inode
+ * @s_inode_size:		Size of an inode
+ * @s_dat_entry_size:		Size of a dat entry
+ * @s_checkpoint_size:		Size of a checkpoint
+ * @s_segment_usage_size:	Size of a segment usage
+ * @s_uuid:			128-bit uuid for volume
+ * @s_volume_name:		volume name
+ * @s_c_interval:		Commit interval of segment
+ * @s_c_block_max:		Threshold of data amount for the
+ *				  segment construction
+ * @s_feature_compat:		Compatible feature set
+ * @s_feature_compat_ro:	Read-only compatible feature set
+ * @s_feature_incompat:		Incompatible feature set
+ * @s_reserved:			padding to the end of the block
  */
 struct nilfs_super_block {
-/*00*/	__le32	s_rev_level;		/* Revision level */
-	__le16	s_minor_rev_level;	/* minor revision level */
-	__le16	s_magic;		/* Magic signature */
-
-	__le16  s_bytes;		/*
-					 * Bytes count of CRC calculation
-					 * for this structure. s_reserved
-					 * is excluded.
-					 */
-	__le16  s_flags;		/* flags */
-	__le32  s_crc_seed;		/* Seed value of CRC calculation */
-/*10*/	__le32	s_sum;			/* Check sum of super block */
-
-	__le32	s_log_block_size;	/*
-					 * Block size represented as follows
-					 * blocksize =
-					 *     1 << (s_log_block_size + 10)
-					 */
-	__le64  s_nsegments;		/* Number of segments in filesystem */
-/*20*/	__le64  s_dev_size;		/* block device size in bytes */
-	__le64	s_first_data_block;	/* 1st seg disk block number */
-/*30*/	__le32  s_blocks_per_segment;   /* number of blocks per full segment */
-	__le32	s_r_segments_percentage; /* Reserved segments percentage */
-
-	__le64  s_last_cno;		/* Last checkpoint number */
-/*40*/	__le64  s_last_pseg;		/* disk block addr pseg written last */
-	__le64  s_last_seq;             /* seq. number of seg written last */
-/*50*/	__le64	s_free_blocks_count;	/* Free blocks count */
-
-	__le64	s_ctime;		/*
-					 * Creation time (execution time of
-					 * newfs)
-					 */
-/*60*/	__le64	s_mtime;		/* Mount time */
-	__le64	s_wtime;		/* Write time */
-/*70*/	__le16	s_mnt_count;		/* Mount count */
-	__le16	s_max_mnt_count;	/* Maximal mount count */
-	__le16	s_state;		/* File system state */
-	__le16	s_errors;		/* Behaviour when detecting errors */
-	__le64	s_lastcheck;		/* time of last check */
-
-/*80*/	__le32	s_checkinterval;	/* max. time between checks */
-	__le32	s_creator_os;		/* OS */
-	__le16	s_def_resuid;		/* Default uid for reserved blocks */
-	__le16	s_def_resgid;		/* Default gid for reserved blocks */
-	__le32	s_first_ino;		/* First non-reserved inode */
-
-/*90*/	__le16  s_inode_size;		/* Size of an inode */
-	__le16  s_dat_entry_size;       /* Size of a dat entry */
-	__le16  s_checkpoint_size;      /* Size of a checkpoint */
-	__le16	s_segment_usage_size;	/* Size of a segment usage */
-
-/*98*/	__u8	s_uuid[16];		/* 128-bit uuid for volume */
-/*A8*/	char	s_volume_name[80]	/* volume name */
-			__kernel_nonstring;
-
-/*F8*/	__le32  s_c_interval;           /* Commit interval of segment */
-	__le32  s_c_block_max;          /*
-					 * Threshold of data amount for
-					 * the segment construction
-					 */
-/*100*/	__le64  s_feature_compat;	/* Compatible feature set */
-	__le64  s_feature_compat_ro;	/* Read-only compatible feature set */
-	__le64  s_feature_incompat;	/* Incompatible feature set */
-	__u32	s_reserved[186];	/* padding to the end of the block */
+/*00*/	__le32	s_rev_level;
+	__le16	s_minor_rev_level;
+	__le16	s_magic;
+
+	__le16  s_bytes;
+	__le16  s_flags;
+	__le32  s_crc_seed;
+/*10*/	__le32	s_sum;
+
+	__le32	s_log_block_size;
+	__le64  s_nsegments;
+/*20*/	__le64  s_dev_size;
+	__le64	s_first_data_block;
+/*30*/	__le32  s_blocks_per_segment;
+	__le32	s_r_segments_percentage;
+
+	__le64  s_last_cno;
+/*40*/	__le64  s_last_pseg;
+	__le64  s_last_seq;
+/*50*/	__le64	s_free_blocks_count;
+
+	__le64	s_ctime;
+/*60*/	__le64	s_mtime;
+	__le64	s_wtime;
+/*70*/	__le16	s_mnt_count;
+	__le16	s_max_mnt_count;
+	__le16	s_state;
+	__le16	s_errors;
+	__le64	s_lastcheck;
+
+/*80*/	__le32	s_checkinterval;
+	__le32	s_creator_os;
+	__le16	s_def_resuid;
+	__le16	s_def_resgid;
+	__le32	s_first_ino;
+
+/*90*/	__le16  s_inode_size;
+	__le16  s_dat_entry_size;
+	__le16  s_checkpoint_size;
+	__le16	s_segment_usage_size;
+
+/*98*/	__u8	s_uuid[16];
+/*A8*/	char	s_volume_name[80]	__kernel_nonstring;
+
+/*F8*/	__le32  s_c_interval;
+	__le32  s_c_block_max;
+
+/*100*/	__le64  s_feature_compat;
+	__le64  s_feature_compat_ro;
+	__le64  s_feature_incompat;
+	__u32	s_reserved[186];
 };
 
 /*
@@ -449,7 +480,7 @@ struct nilfs_btree_node {
 /**
  * struct nilfs_direct_node - header of built-in bmap array
  * @dn_flags: flags
- * @dn_pad: padding
+ * @pad: padding
  */
 struct nilfs_direct_node {
 	__u8 dn_flags;