From c4666114939e3662f0f20763346a767379211db0 Mon Sep 17 00:00:00 2001 From: mav Date: Mon, 21 Mar 2016 00:07:56 +0000 Subject: [PATCH] MFC r295125: MFV r294821: 6529 Properly handle updates of variably-sized SA entries. Reviewed by: Brian Behlendorf Reviewed by: Matthew Ahrens Reviewed by: Ned Bass Reviewed by: Tim Chase Approved by: Gordon Ross Author: Andriy Gapon illumos/illumos-gate@e7e978b1f75353cb29673af9b35453c20c2827bf During the update process in sa_modify_attrs(), the sizes of existing variably-sized SA entries are obtained from sa_lengths[]. The case where a variably-sized SA was being replaced neglected to increment the index into sa_lengths[], so subsequent variable-length SAs would be rewritten with the wrong length. This patch adds the missing increment operation so all variably-sized SA entries are stored with their correct lengths. Another problem was that index into attr_desc[] was increased even when an attribute was removed. If that attribute was not the last attribute, then the last attribute was lost. git-svn-id: svn://svn.freebsd.org/base/stable/10@297106 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f --- .../opensolaris/uts/common/fs/zfs/sa.c | 58 ++++++++++++------- 1 file changed, 36 insertions(+), 22 deletions(-) diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sa.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sa.c index 9293e9a97..200369216 100644 --- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sa.c +++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sa.c @@ -1652,7 +1652,7 @@ sa_modify_attrs(sa_handle_t *hdl, sa_attr_type_t newattr, int spill_data_size = 0; int spill_attr_count = 0; int error; - uint16_t length; + uint16_t length, reg_length; int i, j, k, length_idx; sa_hdr_phys_t *hdr; sa_idx_tab_t *idx_tab; @@ -1712,34 +1712,50 @@ sa_modify_attrs(sa_handle_t *hdl, sa_attr_type_t newattr, hdr = SA_GET_HDR(hdl, SA_BONUS); idx_tab = SA_IDX_TAB_GET(hdl, SA_BONUS); for (; k != 2; k++) { - /* iterate over each attribute in layout */ + /* + * Iterate over each attribute in layout. Fetch the + * size of variable-length attributes needing rewrite + * from sa_lengths[]. + */ for (i = 0, length_idx = 0; i != count; i++) { sa_attr_type_t attr; attr = idx_tab->sa_layout->lot_attrs[i]; - if (attr == newattr) { - /* duplicate attributes are not allowed */ - ASSERT(action == SA_REPLACE || - action == SA_REMOVE); - /* must be variable-sized to be replaced here */ - if (action == SA_REPLACE) { - ASSERT(SA_REGISTERED_LEN(sa, attr) == 0); - SA_ADD_BULK_ATTR(attr_desc, j, attr, - locator, datastart, buflen); - } + reg_length = SA_REGISTERED_LEN(sa, attr); + if (reg_length == 0) { + length = hdr->sa_lengths[length_idx]; + length_idx++; } else { - length = SA_REGISTERED_LEN(sa, attr); - if (length == 0) { - length = hdr->sa_lengths[length_idx]; - } + length = reg_length; + } + if (attr == newattr) { + /* + * There is nothing to do for SA_REMOVE, + * so it is just skipped. + */ + if (action == SA_REMOVE) + continue; + /* + * Duplicate attributes are not allowed, so the + * action can not be SA_ADD here. + */ + ASSERT3S(action, ==, SA_REPLACE); + + /* + * Only a variable-sized attribute can be + * replaced here, and its size must be changing. + */ + ASSERT3U(reg_length, ==, 0); + ASSERT3U(length, !=, buflen); + SA_ADD_BULK_ATTR(attr_desc, j, attr, + locator, datastart, buflen); + } else { SA_ADD_BULK_ATTR(attr_desc, j, attr, NULL, (void *) (TOC_OFF(idx_tab->sa_idx_tab[attr]) + (uintptr_t)old_data[k]), length); } - if (SA_REGISTERED_LEN(sa, attr) == 0) - length_idx++; } if (k == 0 && hdl->sa_spill) { hdr = SA_GET_HDR(hdl, SA_SPILL); @@ -1750,10 +1766,8 @@ sa_modify_attrs(sa_handle_t *hdl, sa_attr_type_t newattr, } } if (action == SA_ADD) { - length = SA_REGISTERED_LEN(sa, newattr); - if (length == 0) { - length = buflen; - } + reg_length = SA_REGISTERED_LEN(sa, newattr); + IMPLY(reg_length != 0, reg_length == buflen); SA_ADD_BULK_ATTR(attr_desc, j, newattr, locator, datastart, buflen); } -- 2.45.0