Subject: + fat-zero-out-seek-range-on-_fat_get_block.patch added to -mm tree To: namjae.jeon@xxxxxxxxxxx,a.sahrawat@xxxxxxxxxxx,hirofumi@xxxxxxxxxxxxxxxxxx From: akpm@xxxxxxxxxxxxxxxxxxxx Date: Tue, 07 Jan 2014 15:18:53 -0800 The patch titled Subject: fat: zero out seek range on _fat_get_block has been added to the -mm tree. Its filename is fat-zero-out-seek-range-on-_fat_get_block.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/fat-zero-out-seek-range-on-_fat_get_block.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/fat-zero-out-seek-range-on-_fat_get_block.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Namjae Jeon <namjae.jeon@xxxxxxxxxxx> Subject: fat: zero out seek range on _fat_get_block For normal buffered write operations, normally if we try to write to an offset > than file size, it does a cont_expand_zero till that offset. Now, in case of fallocated regions, since the blocks are already allocated. So, make it zero out that buffers for those blocks till the seek'ed offset. Signed-off-by: Namjae Jeon <namjae.jeon@xxxxxxxxxxx> Signed-off-by: Amit Sahrawat <a.sahrawat@xxxxxxxxxxx> Cc: OGAWA Hirofumi <hirofumi@xxxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/fat/inode.c | 24 +++++++++++++++++++++++- 1 file changed, 23 insertions(+), 1 deletion(-) diff -puN fs/fat/inode.c~fat-zero-out-seek-range-on-_fat_get_block fs/fat/inode.c --- a/fs/fat/inode.c~fat-zero-out-seek-range-on-_fat_get_block +++ a/fs/fat/inode.c @@ -54,6 +54,25 @@ static int fat_add_cluster(struct inode return err; } +static void check_fallocated_region(struct inode *inode, sector_t iblock, + unsigned long *max_blocks, struct buffer_head *bh_result) +{ + struct super_block *sb = inode->i_sb; + sector_t last_block, disk_block; + const unsigned long blocksize = sb->s_blocksize; + const unsigned char blocksize_bits = sb->s_blocksize_bits; + + last_block = (MSDOS_I(inode)->mmu_private + (blocksize - 1)) + >> blocksize_bits; + disk_block = (MSDOS_I(inode)->i_disksize + (blocksize - 1)) + >> blocksize_bits; + if (iblock >= last_block && iblock <= disk_block) { + MSDOS_I(inode)->mmu_private += *max_blocks << blocksize_bits; + set_buffer_new(bh_result); + } + +} + static inline int __fat_get_block(struct inode *inode, sector_t iblock, unsigned long *max_blocks, struct buffer_head *bh_result, int create) @@ -68,8 +87,11 @@ static inline int __fat_get_block(struct if (err) return err; if (phys) { - map_bh(bh_result, sb, phys); *max_blocks = min(mapped_blocks, *max_blocks); + if (create) + check_fallocated_region(inode, iblock, max_blocks, + bh_result); + map_bh(bh_result, sb, phys); return 0; } if (!create) _ Patches currently in -mm which might be from namjae.jeon@xxxxxxxxxxx are fat-add-i_disksize-to-represent-uninitialized-size.patch fat-add-fat_fallocate-operation.patch fat-zero-out-seek-range-on-_fat_get_block.patch fat-fallback-to-buffered-write-in-case-of-fallocated-region-on-direct-io.patch fat-permit-to-return-phy-block-number-by-fibmap-in-fallocated-region.patch fat-update-the-limitation-for-fat-fallocate.patch linux-next.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html