From: Andrew Morton We need set_page_dirty() to return true if it actually transitioned the page from a clean to dirty state. This wasn't right in a couple of places. Do a kernel-wide audit, fix things up. This leaves open the possibility of returning a negative errno from set_page_dirty() sometime in the future. But we don't do that at present. Signed-off-by: Andrew Morton --- arch/cris/arch-v32/drivers/cryptocop.c | 2 +- drivers/block/rd.c | 3 ++- fs/buffer.c | 2 +- include/linux/fs.h | 2 +- mm/page-writeback.c | 11 ++++++----- 5 files changed, 11 insertions(+), 9 deletions(-) diff -puN arch/cris/arch-v32/drivers/cryptocop.c~set_page_dirty-return-value-fixes arch/cris/arch-v32/drivers/cryptocop.c --- devel/arch/cris/arch-v32/drivers/cryptocop.c~set_page_dirty-return-value-fixes 2006-02-10 14:59:04.000000000 -0800 +++ devel-akpm/arch/cris/arch-v32/drivers/cryptocop.c 2006-02-10 14:59:04.000000000 -0800 @@ -2944,7 +2944,7 @@ static int cryptocop_ioctl_process(struc int spdl_err; /* Mark output pages dirty. */ spdl_err = set_page_dirty_lock(outpages[i]); - DEBUG(if (spdl_err)printk("cryptocop_ioctl_process: set_page_dirty_lock returned %d\n", spdl_err)); + DEBUG(if (spdl_err < 0)printk("cryptocop_ioctl_process: set_page_dirty_lock returned %d\n", spdl_err)); } for (i = 0; i < nooutpages; i++){ put_page(outpages[i]); diff -puN drivers/block/rd.c~set_page_dirty-return-value-fixes drivers/block/rd.c --- devel/drivers/block/rd.c~set_page_dirty-return-value-fixes 2006-02-10 14:59:04.000000000 -0800 +++ devel-akpm/drivers/block/rd.c 2006-02-10 14:59:04.000000000 -0800 @@ -186,7 +186,8 @@ static int ramdisk_writepages(struct add */ static int ramdisk_set_page_dirty(struct page *page) { - SetPageDirty(page); + if (!TestSetPageDirty(page)) + return 1; return 0; } diff -puN fs/buffer.c~set_page_dirty-return-value-fixes fs/buffer.c --- devel/fs/buffer.c~set_page_dirty-return-value-fixes 2006-02-10 14:59:04.000000000 -0800 +++ devel-akpm/fs/buffer.c 2006-02-10 14:59:04.000000000 -0800 @@ -865,8 +865,8 @@ int __set_page_dirty_buffers(struct page } write_unlock_irq(&mapping->tree_lock); __mark_inode_dirty(mapping->host, I_DIRTY_PAGES); + return 1; } - return 0; } EXPORT_SYMBOL(__set_page_dirty_buffers); diff -puN include/linux/fs.h~set_page_dirty-return-value-fixes include/linux/fs.h --- devel/include/linux/fs.h~set_page_dirty-return-value-fixes 2006-02-10 14:59:04.000000000 -0800 +++ devel-akpm/include/linux/fs.h 2006-02-10 14:59:04.000000000 -0800 @@ -347,7 +347,7 @@ struct address_space_operations { /* Write back some dirty pages from this mapping. */ int (*writepages)(struct address_space *, struct writeback_control *); - /* Set a page dirty */ + /* Set a page dirty. Return true if this dirtied it */ int (*set_page_dirty)(struct page *page); int (*readpages)(struct file *filp, struct address_space *mapping, diff -puN mm/page-writeback.c~set_page_dirty-return-value-fixes mm/page-writeback.c --- devel/mm/page-writeback.c~set_page_dirty-return-value-fixes 2006-02-10 14:59:04.000000000 -0800 +++ devel-akpm/mm/page-writeback.c 2006-02-10 14:59:04.000000000 -0800 @@ -628,8 +628,6 @@ EXPORT_SYMBOL(write_one_page); */ int __set_page_dirty_nobuffers(struct page *page) { - int ret = 0; - if (!TestSetPageDirty(page)) { struct address_space *mapping = page_mapping(page); struct address_space *mapping2; @@ -651,8 +649,9 @@ int __set_page_dirty_nobuffers(struct pa I_DIRTY_PAGES); } } + return 1; } - return ret; + return 0; } EXPORT_SYMBOL(__set_page_dirty_nobuffers); @@ -682,8 +681,10 @@ int fastcall set_page_dirty(struct page return (*spd)(page); return __set_page_dirty_buffers(page); } - if (!PageDirty(page)) - SetPageDirty(page); + if (!PageDirty(page)) { + if (!TestSetPageDirty(page)) + return 1; + } return 0; } EXPORT_SYMBOL(set_page_dirty); _