Hi all, Here is the v3 of extent status tree. In this version, the biggest change is the i_es_lock (a rwlock_t) instead of i_data_sem, which is introduced to protect extent status tree. Moreover I improve the SEEK_DATA/SEEK_HOLE. In previous version, the unwritten extent is as a data, and now it will lookup page cache to determine it as a data or a hole. When it has some data at the given range, the unwritten extent will be as a data. Otherwise, it will be as a hole. Other changes contain some bug fixes. About introduction of extent status tree and future works in step2, please see the comments in patch 2. Here is a defect after introducing SEEK_DATA/SEEK_HOLE support, which will cause xfstest #285 failure when the file is block-mapped because in ext4 fallocate(2) is not supported by block-mapped file. However, in current version of xfstest, it cannot trigger any failure because in xfstest the test case has a bug that will cause no error is reported from #285. I have submitted a patch to fix it, but it still doesn't be applied. Thus, if someone are willing to test SEEK_DATA/SEEK_HOLE patch, please apply this patch firstly [1]. 1. http://patchwork.xfs.org/patch/4276/ I really thanks Jeff Liu, who gives me some advices and inspires me about SEEK_DATA/SEEK_HOLE improvement, and the function, which looks up page cache to determine whether an unwritten extent is as a data or a hole, is inspired by his work for xfs (d126d43f631f996daeee5006714fed914be32368). Thus, I add a Signed-off-by for his crediting. Jeff, I really appreicate if you could allow me to add Signed-off-by in patch 8. If doing like this is incorrect, please let me know. Thanks! v3 <- v2: - add rwlock to protect extent status tree - improve SEEK_DATA/SEEK_HOLE - fix some bugs Here is the second version: http://lwn.net/Articles/512899/ v2 <- v1: - add a BUG_ON to do a sanity check in extent_status_end - fix off-by-one problem in extent_status_end accroding to Lukas's comment - add more detailed comments in ext4_es_find_extent - try to lookup in extent tree cache firstly in ext4_es_find_extent - rename ext4_es_add_space to ext4_es_insert_extent - rename ext4_es_remove_space to ext4_es_remove_extent The first version is in this link: http://www.spinics.net/lists/linux-ext4/msg33101.html Any feedbacks are appreciated. Thanks! Regards, Zheng --- Zheng Liu (8): ext4: add two structures supporting extent status tree ext4: add operations on extent status tree ext4: initialize extent status tree ext4: let ext4 maintain extent status tree ext4: add some tracepoints in extent status tree ext4: reimplement ext4_find_delay_alloc_range on extent status tree ext4: reimplement fiemap on extent status tree ext4: introduce lseek SEEK_DATA/SEEK_HOLE support fs/ext4/Makefile | 2 +- fs/ext4/ext4.h | 10 +- fs/ext4/ext4_extents.h | 3 +- fs/ext4/extents.c | 305 +++++----------------------------- fs/ext4/extents_status.c | 499 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ fs/ext4/extents_status.h | 45 +++++ fs/ext4/file.c | 334 ++++++++++++++++++++++++++++++++++++- fs/ext4/indirect.c | 1 + fs/ext4/inode.c | 91 ++++------ fs/ext4/super.c | 14 +- include/trace/events/ext4.h | 101 +++++++++++ 11 files changed, 1078 insertions(+), 327 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
