diff options
Diffstat (limited to 'module/zfs/zfs_znode.c')
| -rw-r--r-- | module/zfs/zfs_znode.c | 119 |
1 files changed, 114 insertions, 5 deletions
diff --git a/module/zfs/zfs_znode.c b/module/zfs/zfs_znode.c index 5fcb9e930..f2e305f7a 100644 --- a/module/zfs/zfs_znode.c +++ b/module/zfs/zfs_znode.c @@ -1345,6 +1345,50 @@ zfs_extend(znode_t *zp, uint64_t end) } /* + * zfs_zero_partial_page - Modeled after update_pages() but + * with different arguments and semantics for use by zfs_freesp(). + * + * Zeroes a piece of a single page cache entry for zp at offset + * start and length len. + * + * Caller must acquire a range lock on the file for the region + * being zeroed in order that the ARC and page cache stay in sync. + */ +static void +zfs_zero_partial_page(znode_t *zp, uint64_t start, uint64_t len) +{ + struct address_space *mp = ZTOI(zp)->i_mapping; + struct page *pp; + int64_t off; + void *pb; + + ASSERT((start & PAGE_CACHE_MASK) == + ((start + len - 1) & PAGE_CACHE_MASK)); + + off = start & (PAGE_CACHE_SIZE - 1); + start &= PAGE_CACHE_MASK; + + pp = find_lock_page(mp, start >> PAGE_CACHE_SHIFT); + if (pp) { + if (mapping_writably_mapped(mp)) + flush_dcache_page(pp); + + pb = kmap(pp); + bzero(pb + off, len); + kunmap(pp); + + if (mapping_writably_mapped(mp)) + flush_dcache_page(pp); + + mark_page_accessed(pp); + SetPageUptodate(pp); + ClearPageError(pp); + unlock_page(pp); + page_cache_release(pp); + } +} + +/* * Free space in a file. * * IN: zp - znode of file to free data in. @@ -1378,6 +1422,40 @@ zfs_free_range(znode_t *zp, uint64_t off, uint64_t len) error = dmu_free_long_range(zsb->z_os, zp->z_id, off, len); + /* + * Zero partial page cache entries. This must be done under a + * range lock in order to keep the ARC and page cache in sync. + */ + if (zp->z_is_mapped) { + loff_t first_page, last_page, page_len; + loff_t first_page_offset, last_page_offset; + + /* first possible full page in hole */ + first_page = (off + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; + /* last page of hole */ + last_page = (off + len) >> PAGE_CACHE_SHIFT; + + /* offset of first_page */ + first_page_offset = first_page << PAGE_CACHE_SHIFT; + /* offset of last_page */ + last_page_offset = last_page << PAGE_CACHE_SHIFT; + + if (first_page > last_page) { + /* entire punched area within a single page */ + zfs_zero_partial_page(zp, off, len); + } else { + /* beginning of punched area at the end of a page */ + page_len = first_page_offset - off; + if (page_len > 0) + zfs_zero_partial_page(zp, off, page_len); + + /* end of punched area at the beginning of a page */ + page_len = off + len - last_page_offset; + if (page_len > 0) + zfs_zero_partial_page(zp, last_page_offset, + page_len); + } + } zfs_range_unlock(rl); return (error); @@ -1479,8 +1557,7 @@ zfs_freesp(znode_t *zp, uint64_t off, uint64_t len, int flag, boolean_t log) error = zfs_extend(zp, off+len); if (error == 0 && log) goto log; - else - return (error); + goto out; } /* @@ -1500,7 +1577,7 @@ zfs_freesp(znode_t *zp, uint64_t off, uint64_t len, int flag, boolean_t log) error = zfs_extend(zp, off+len); } if (error || !log) - return (error); + goto out; log: tx = dmu_tx_create(zsb->z_os); dmu_tx_hold_sa(tx, zp->z_sa_hdl, B_FALSE); @@ -1508,7 +1585,7 @@ log: error = dmu_tx_assign(tx, TXG_WAIT); if (error) { dmu_tx_abort(tx); - return (error); + goto out; } SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_MTIME(zsb), NULL, mtime, 16); @@ -1522,8 +1599,40 @@ log: zfs_log_truncate(zilog, tx, TX_TRUNCATE, zp, off, len); dmu_tx_commit(tx); + zfs_inode_update(zp); - return (0); + error = 0; + +out: + /* + * Truncate the page cache - for file truncate operations, use + * the purpose-built API for truncations. For punching operations, + * truncate only whole pages within the region; partial pages are + * zeroed under a range lock in zfs_free_range(). + */ + if (len == 0) + truncate_setsize(ZTOI(zp), off); + else if (zp->z_is_mapped) { + loff_t first_page, last_page; + loff_t first_page_offset, last_page_offset; + + /* first possible full page in hole */ + first_page = (off + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; + /* last page of hole */ + last_page = (off + len) >> PAGE_CACHE_SHIFT; + + /* offset of first_page */ + first_page_offset = first_page << PAGE_CACHE_SHIFT; + /* offset of last_page */ + last_page_offset = last_page << PAGE_CACHE_SHIFT; + + /* truncate whole pages */ + if (last_page_offset > first_page_offset) { + truncate_inode_pages_range(ZTOI(zp)->i_mapping, + first_page_offset, last_page_offset - 1); + } + } + return (error); } void |