From 22ddc556380cf5645c52292b6d980766646eb864 Mon Sep 17 00:00:00 2001 From: Boaz Harrosh Date: Tue, 19 Jan 2010 19:24:45 +0200 Subject: [PATCH] exofs: Recover in the case of read-passed-end-of-file In check_io, implement the case of reading passed end of file, by clearing the pages and recover with no error. In a raid arrangement this can become a legitimate situation in case of holes in the file. Signed-off-by: Boaz Harrosh --- fs/exofs/ios.c | 36 ++++++++++++++++++++++++++++++------ 1 file changed, 30 insertions(+), 6 deletions(-) diff --git a/fs/exofs/ios.c b/fs/exofs/ios.c index 3cc0dd3f0eb2..439c5d097b27 100644 --- a/fs/exofs/ios.c +++ b/fs/exofs/ios.c @@ -173,6 +173,21 @@ static int exofs_io_execute(struct exofs_io_state *ios) return ret; } +static void _clear_bio(struct bio *bio) +{ + struct bio_vec *bv; + unsigned i; + + __bio_for_each_segment(bv, bio, i, 0) { + unsigned this_count = bv->bv_len; + + if (likely(PAGE_SIZE == this_count)) + clear_highpage(bv->bv_page); + else + zero_user(bv->bv_page, bv->bv_offset, this_count); + } +} + int exofs_check_io(struct exofs_io_state *ios, u64 *resid) { enum osd_err_priority acumulated_osd_err = 0; @@ -181,16 +196,25 @@ int exofs_check_io(struct exofs_io_state *ios, u64 *resid) for (i = 0; i < ios->numdevs; i++) { struct osd_sense_info osi; - int ret = osd_req_decode_sense(ios->per_dev[i].or, &osi); + struct osd_request *or = ios->per_dev[i].or; + int ret; + + if (unlikely(!or)) + continue; + ret = osd_req_decode_sense(or, &osi); if (likely(!ret)) continue; - if (unlikely(ret == -EFAULT)) { - EXOFS_DBGMSG("%s: EFAULT Need page clear\n", __func__); - /*FIXME: All the pages in this device range should: - * clear_highpage(page); - */ + if (OSD_ERR_PRI_CLEAR_PAGES == osi.osd_err_pri) { + /* start read offset passed endof file */ + _clear_bio(ios->per_dev[i].bio); + EXOFS_DBGMSG("start read offset passed end of file " + "offset=0x%llx, length=0x%llx\n", + _LLU(ios->offset), + _LLU(ios->length)); + + continue; /* we recovered */ } if (osi.osd_err_pri >= acumulated_osd_err) { -- GitLab