The compiler, at least for ix86 and m68k, validly warns that the comparison: next <= (loff_t)-1 is always true (and it's always true also for x86-64 and probably all other arches - as long as pgoff_t isn't wider than loff_t). The intention appears to be to avoid wrapping of "next", so rather than eliminating the pointless comparison, fix the loop to indeed get exited when "next" would otherwise wrap. On m68k the following warning is observed: fs/fscache/page.c: In function '__fscache_uncache_all_inode_pages': fs/fscache/page.c:979: warning: comparison is always false due to limited range of data type
Unified · Split
| @@ -976,16 +976,12 @@ void __fscache_uncache_all_inode_pages(struct fscache_cookie *cookie, · 975 unmodified lines | ||
| 976 | 976 | |
| 977 | 977 | pagevec_init(&pvec, 0); |
| 978 | 978 | next = 0; |
| 979 | − while (next <= (loff_t)-1 && | |
| 980 | − pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE) | |
| 981 | − ) { | |
| 979 | + do { | |
| 980 | + if (!pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) | |
| 981 | + break; | |
| 982 | 982 | for (i = 0; i < pagevec_count(&pvec); i++) { |
| 983 | 983 | struct page *page = pvec.pages[i]; |
| 984 | − pgoff_t page_index = page->index; | |
| 985 | − | |
| 986 | − ASSERTCMP(page_index, >=, next); | |
| 987 | − next = page_index + 1; | |
| 988 | − | |
| 984 | + next = page->index; | |
| 989 | 985 | if (PageFsCache(page)) { |
| 990 | 986 | __fscache_wait_on_page_write(cookie, page); |
| 991 | 987 | __fscache_uncache_page(cookie, page); |
| @@ -993,7 +989,7 @@ void __fscache_uncache_all_inode_pages(struct fscache_cookie *cookie, · 1 unmodified line | ||
| 993 | 989 | } |
| 994 | 990 | pagevec_release(&pvec); |
| 995 | 991 | cond_resched(); |
| 996 | − } | |
| 992 | + } while (++next); | |
| 997 | 993 | |
| 998 | 994 | _leave(""); |
| 999 | 995 | } |