fs: Add uoff_t

In a recent commit, I inadvertently changed a comparison from being an unsigned comparison (on 64-bit systems) to being a signed comparison (which it had always been on 32-bit systems). This led to a sporadic fstests failure. To make sure this comparison is always unsigned, introduce a new type, uoff_t which is the unsigned version of loff_t. Generally file sizes are restricted to being a signed integer, but in these two places it is convenient to pass -1 to indicate "up to the end of the file".

Matthew Wilcox (Oracle) committed 11 months ago

Commit 37d369f1 parent a77a5956 files · +11 −9Browse files

Unified · Split

6 files

include/linux/mm.h +4 −4
include/linux/shmem_fs.h +1 −1
include/linux/types.h +1 −0
include/uapi/asm-generic/posix_types.h +1 −0
mm/shmem.c +3 −3
mm/truncate.c +1 −1

include/linux/mm.h+4−4

@@ -3495,10 +3495,10 @@ struct vm_unmapped_area_info { · 3494 unmodified lines
3495	3495	extern unsigned long vm_unmapped_area(struct vm_unmapped_area_info *info);
3496	3496
3497	3497	/* truncate.c */
3498		−extern void truncate_inode_pages(struct address_space *, loff_t);
3499		−extern void truncate_inode_pages_range(struct address_space *,
3500		− loff_t lstart, loff_t lend);
3501		−extern void truncate_inode_pages_final(struct address_space *);
	3498	+void truncate_inode_pages(struct address_space *mapping, loff_t lstart);
	3499	+void truncate_inode_pages_range(struct address_space *mapping, loff_t lstart,
	3500	+ uoff_t lend);
	3501	+void truncate_inode_pages_final(struct address_space *mapping);
3502	3502
3503	3503	/* generic vm_area_ops exported for stackable file systems */
3504	3504	extern vm_fault_t filemap_fault(struct vm_fault *vmf);

include/linux/shmem_fs.h+1−1

@@ -111,7 +111,7 @@ struct page shmem_read_mapping_page_gfp(struct address_space mapping, · 110 unmodified lines
111	111	pgoff_t index, gfp_t gfp_mask);
112	112	int shmem_writeout(struct folio folio, struct swap_iocb *plug,
113	113	struct list_head *folio_list);
114		−void shmem_truncate_range(struct inode *inode, loff_t start, loff_t end);
	114	+void shmem_truncate_range(struct inode *inode, loff_t start, uoff_t end);
115	115	int shmem_unuse(unsigned int type);
116	116
117	117	#ifdef CONFIG_TRANSPARENT_HUGEPAGE

include/linux/types.h+1−0

@@ -50,6 +50,7 @@ typedef __kernel_old_gid_t old_gid_t; · 49 unmodified lines
50	50
51	51	#if defined(__GNUC__)
52	52	typedef __kernel_loff_t loff_t;
	53	+typedef __kernel_uoff_t uoff_t;
53	54	#endif
54	55
55	56	/*

include/uapi/asm-generic/posix_types.h+1−0

@@ -86,6 +86,7 @@ typedef struct { · 85 unmodified lines
86	86	*/
87	87	typedef __kernel_long_t __kernel_off_t;
88	88	typedef long long __kernel_loff_t;
	89	+typedef unsigned long long __kernel_uoff_t;
89	90	typedef __kernel_long_t __kernel_old_time_t;
90	91	#ifndef __KERNEL__
91	92	typedef __kernel_long_t __kernel_time_t;

mm/shmem.c+3−3

@@ -1076,7 +1076,7 @@ static struct folio shmem_get_partial_folio(struct inode inode, pgoff_t index) · 1075 unmodified lines
1076	1076	* Remove range of pages and swap entries from page cache, and free them.
1077	1077	* If !unfalloc, truncate or punch hole; if unfalloc, undo failed fallocate.
1078	1078	*/
1079		−static void shmem_undo_range(struct inode *inode, loff_t lstart, loff_t lend,
	1079	+static void shmem_undo_range(struct inode *inode, loff_t lstart, uoff_t lend,
1080	1080	bool unfalloc)
1081	1081	{
1082	1082	struct address_space *mapping = inode->i_mapping;
@@ -1227,7 +1227,7 @@ whole_folios: · 144 unmodified lines
1227	1227	shmem_recalc_inode(inode, 0, -nr_swaps_freed);
1228	1228	}
1229	1229
1230		−void shmem_truncate_range(struct inode *inode, loff_t lstart, loff_t lend)
	1230	+void shmem_truncate_range(struct inode *inode, loff_t lstart, uoff_t lend)
1231	1231	{
1232	1232	shmem_undo_range(inode, lstart, lend, false);
1233	1233	inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode));
@@ -5776,7 +5776,7 @@ unsigned long shmem_get_unmapped_area(struct file *file, · 4542 unmodified lines
5776	5776	}
5777	5777	#endif
5778	5778
5779		−void shmem_truncate_range(struct inode *inode, loff_t lstart, loff_t lend)
	5779	+void shmem_truncate_range(struct inode *inode, loff_t lstart, uoff_t lend)
5780	5780	{
5781	5781	truncate_inode_pages_range(inode->i_mapping, lstart, lend);
5782	5782	}

mm/truncate.c+1−1

@@ -339,7 +339,7 @@ long mapping_evict_folio(struct address_space mapping, struct folio folio) · 338 unmodified lines
339	339	* page aligned properly.
340	340	*/
341	341	void truncate_inode_pages_range(struct address_space *mapping,
342		− loff_t lstart, loff_t lend)
	342	+ loff_t lstart, uoff_t lend)
343	343	{
344	344	pgoff_t start; /* inclusive */
345	345	pgoff_t end; /* exclusive */