Author: mav Date: Tue Jan 26 13:49:46 2016 New Revision: 294821 URL: https://svnweb.freebsd.org/changeset/base/294821
Log: 6529 Properly handle updates of variably-sized SA entries. Reviewed by: Brian Behlendorf <[email protected]> Reviewed by: Matthew Ahrens <[email protected]> Reviewed by: Ned Bass <[email protected]> Reviewed by: Tim Chase <[email protected]> Approved by: Gordon Ross <[email protected]> Author: Andriy Gapon <[email protected]> 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. Modified: vendor-sys/illumos/dist/uts/common/fs/zfs/sa.c Modified: vendor-sys/illumos/dist/uts/common/fs/zfs/sa.c ============================================================================== --- vendor-sys/illumos/dist/uts/common/fs/zfs/sa.c Tue Jan 26 13:45:41 2016 (r294820) +++ vendor-sys/illumos/dist/uts/common/fs/zfs/sa.c Tue Jan 26 13:49:46 2016 (r294821) @@ -1628,8 +1628,11 @@ sa_replace_all_by_template(sa_handle_t * } /* - * add/remove/replace a single attribute and then rewrite the entire set + * Add/remove a single attribute or replace a variable-sized attribute value + * with a value of a different size, and then rewrite the entire set * of attributes. + * Same-length attribute value replacement (including fixed-length attributes) + * is handled more efficiently by the upper layers. */ static int sa_modify_attrs(sa_handle_t *hdl, sa_attr_type_t newattr, @@ -1646,7 +1649,7 @@ sa_modify_attrs(sa_handle_t *hdl, sa_att 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; @@ -1706,26 +1709,45 @@ sa_modify_attrs(sa_handle_t *hdl, sa_att 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]; + reg_length = SA_REGISTERED_LEN(sa, attr); + if (reg_length == 0) { + length = hdr->sa_lengths[length_idx]; + length_idx++; + } else { + length = reg_length; + } if (attr == newattr) { - if (action == SA_REMOVE) { - j++; + /* + * There is nothing to do for SA_REMOVE, + * so it is just skipped. + */ + if (action == SA_REMOVE) continue; - } - ASSERT(SA_REGISTERED_LEN(sa, attr) == 0); - ASSERT(action == SA_REPLACE); + + /* + * 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 { - length = SA_REGISTERED_LEN(sa, attr); - if (length == 0) { - length = hdr->sa_lengths[length_idx++]; - } - SA_ADD_BULK_ATTR(attr_desc, j, attr, NULL, (void *) (TOC_OFF(idx_tab->sa_idx_tab[attr]) + @@ -1741,13 +1763,12 @@ sa_modify_attrs(sa_handle_t *hdl, sa_att } } 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); } + ASSERT3U(j, ==, attr_count); error = sa_build_layouts(hdl, attr_desc, attr_count, tx); _______________________________________________ [email protected] mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "[email protected]"
