MFV r294821: 6529 Properly handle updates of variably-sized SA entries.

Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Ned Bass <bass6@llnl.gov>
Reviewed by: Tim Chase <tim@chase2k.com>
Approved by: Gordon Ross <gwr@nexenta.com>
Author: Andriy Gapon <avg@icyb.net.ua>

illumos/illumos-gate@e7e978b1f7

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.
This commit is contained in:
Andriy Gapon 2016-02-01 15:40:40 +00:00
commit 984777c43f

View File

@ -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);
}