| Message ID | 20180702125036.GA3366@lst.de (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
On Mon, Jul 02, 2018 at 02:50:36PM +0200, Christoph Hellwig wrote: > The problem is that we need to split extents at the eof block > so that the existing zeroing actually takes effect. The patch below > fixes the test case for me: > Looks sane at a glance. I'll take a closer look at v7 and run some more testing.. Brian > diff --git a/fs/iomap.c b/fs/iomap.c > index e8f1bcdc95cf..9c88b8736de0 100644 > --- a/fs/iomap.c > +++ b/fs/iomap.c > @@ -143,13 +143,20 @@ static void > iomap_adjust_read_range(struct inode *inode, struct iomap_page *iop, > loff_t *pos, loff_t length, unsigned *offp, unsigned *lenp) > { > + unsigned block_bits = inode->i_blkbits; > + unsigned block_size = (1 << block_bits); > unsigned poff = *pos & (PAGE_SIZE - 1); > unsigned plen = min_t(loff_t, PAGE_SIZE - poff, length); > + unsigned first = poff >> block_bits; > + unsigned last = (poff + plen - 1) >> block_bits; > + unsigned end = (i_size_read(inode) & (PAGE_SIZE - 1)) >> block_bits; > > + /* > + * If the block size is smaller than the page size we need to check the > + * per-block uptodate status and adjust the offset and length if needed > + * to avoid reading in already uptodate ranges. > + */ > if (iop) { > - unsigned block_size = i_blocksize(inode); > - unsigned first = poff >> inode->i_blkbits; > - unsigned last = (poff + plen - 1) >> inode->i_blkbits; > unsigned int i; > > /* move forward for each leading block marked uptodate */ > @@ -159,17 +166,27 @@ iomap_adjust_read_range(struct inode *inode, struct iomap_page *iop, > *pos += block_size; > poff += block_size; > plen -= block_size; > + first++; > } > > /* truncate len if we find any trailing uptodate block(s) */ > for ( ; i <= last; i++) { > if (test_bit(i, iop->uptodate)) { > plen -= (last - i + 1) * block_size; > + last = i - 1; > break; > } > } > } > > + /* > + * If the extent spans the block that contains the i_size we need to > + * handle both halves separately so that we properly zero data in the > + * page cache for blocks that are entirely outside of i_size. > + */ > + if (first <= end && last > end) > + plen -= (last - end) * block_size; > + > *offp = poff; > *lenp = plen; > } > -- > To unsubscribe from this list: send the line "unsubscribe linux-xfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/iomap.c b/fs/iomap.c index e8f1bcdc95cf..9c88b8736de0 100644 --- a/fs/iomap.c +++ b/fs/iomap.c @@ -143,13 +143,20 @@ static void iomap_adjust_read_range(struct inode *inode, struct iomap_page *iop, loff_t *pos, loff_t length, unsigned *offp, unsigned *lenp) { + unsigned block_bits = inode->i_blkbits; + unsigned block_size = (1 << block_bits); unsigned poff = *pos & (PAGE_SIZE - 1); unsigned plen = min_t(loff_t, PAGE_SIZE - poff, length); + unsigned first = poff >> block_bits; + unsigned last = (poff + plen - 1) >> block_bits; + unsigned end = (i_size_read(inode) & (PAGE_SIZE - 1)) >> block_bits; + /* + * If the block size is smaller than the page size we need to check the + * per-block uptodate status and adjust the offset and length if needed + * to avoid reading in already uptodate ranges. + */ if (iop) { - unsigned block_size = i_blocksize(inode); - unsigned first = poff >> inode->i_blkbits; - unsigned last = (poff + plen - 1) >> inode->i_blkbits; unsigned int i; /* move forward for each leading block marked uptodate */ @@ -159,17 +166,27 @@ iomap_adjust_read_range(struct inode *inode, struct iomap_page *iop, *pos += block_size; poff += block_size; plen -= block_size; + first++; } /* truncate len if we find any trailing uptodate block(s) */ for ( ; i <= last; i++) { if (test_bit(i, iop->uptodate)) { plen -= (last - i + 1) * block_size; + last = i - 1; break; } } } + /* + * If the extent spans the block that contains the i_size we need to + * handle both halves separately so that we properly zero data in the + * page cache for blocks that are entirely outside of i_size. + */ + if (first <= end && last > end) + plen -= (last - end) * block_size; + *offp = poff; *lenp = plen; }