[SCSI] libosd: attributes Support

Support for both List-Mode and Page-Mode osd attributes. One of
these operations may be added to most other operations.

Define the OSD standard's attribute pages constants and structures
(osd_attributes.h)

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Reviewed-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

1 files changed, 579 insertions, 0 deletions

diff --git a/drivers/scsi/osd/osd_initiator.c b/drivers/scsi/osd/osd_initiator.c
index 0e6d906f1113..b982d767bf99 100644
--- a/drivers/scsi/osd/osd_initiator.c
+++ b/drivers/scsi/osd/osd_initiator.c
@@ -45,6 +45,10 @@
 
 #include "osd_debug.h"
 
+#ifndef __unused
+#    define __unused                    __attribute__((unused))
+#endif
+
 enum { OSD_REQ_RETRIES = 1 };
 
 MODULE_AUTHOR("Boaz Harrosh <bharrosh@panasas.com>");
@@ -63,6 +67,50 @@ static unsigned _osd_req_cdb_len(struct osd_request *or)
         return OSDv1_TOTAL_CDB_LEN;
 }
 
+static unsigned _osd_req_alist_elem_size(struct osd_request *or, unsigned len)
+{
+        return osdv1_attr_list_elem_size(len);
+}
+
+static unsigned _osd_req_alist_size(struct osd_request *or, void *list_head)
+{
+        return osdv1_list_size(list_head);
+}
+
+static unsigned _osd_req_sizeof_alist_header(struct osd_request *or)
+{
+        return sizeof(struct osdv1_attributes_list_header);
+}
+
+static void _osd_req_set_alist_type(struct osd_request *or,
+        void *list, int list_type)
+{
+        struct osdv1_attributes_list_header *attr_list = list;
+
+        memset(attr_list, 0, sizeof(*attr_list));
+        attr_list->type = list_type;
+}
+
+static bool _osd_req_is_alist_type(struct osd_request *or,
+        void *list, int list_type)
+{
+        if (!list)
+                return false;
+
+        if (1) {
+                struct osdv1_attributes_list_header *attr_list = list;
+
+                return attr_list->type == list_type;
+        }
+}
+
+static osd_cdb_offset osd_req_encode_offset(struct osd_request *or,
+        u64 offset, unsigned *padding)
+{
+        return __osd_encode_offset(offset, padding,
+                                  OSDv1_OFFSET_MIN_SHIFT, OSD_OFFSET_MAX_SHIFT);
+}
+
 void osd_dev_init(struct osd_dev *osdd, struct scsi_device *scsi_device)
 {
         memset(osdd, 0, sizeof(*osdd));
@@ -125,10 +173,25 @@ static void _abort_unexecuted_bios(struct request *rq)
         }
 }
 
+static void _osd_free_seg(struct osd_request *or __unused,
+        struct _osd_req_data_segment *seg)
+{
+        if (!seg->buff || !seg->alloc_size)
+                return;
+
+        kfree(seg->buff);
+        seg->buff = NULL;
+        seg->alloc_size = 0;
+}
+
 void osd_end_request(struct osd_request *or)
 {
         struct request *rq = or->request;
 
+        _osd_free_seg(or, &or->set_attr);
+        _osd_free_seg(or, &or->enc_get_attr);
+        _osd_free_seg(or, &or->get_attr);
+
         if (rq) {
                 if (rq->next_rq) {
                         _abort_unexecuted_bios(rq->next_rq);
@@ -176,6 +239,54 @@ int osd_execute_request_async(struct osd_request *or,
 }
 EXPORT_SYMBOL(osd_execute_request_async);
 
+u8 sg_out_pad_buffer[1 << OSDv1_OFFSET_MIN_SHIFT];
+u8 sg_in_pad_buffer[1 << OSDv1_OFFSET_MIN_SHIFT];
+
+static int _osd_realloc_seg(struct osd_request *or,
+        struct _osd_req_data_segment *seg, unsigned max_bytes)
+{
+        void *buff;
+
+        if (seg->alloc_size >= max_bytes)
+                return 0;
+
+        buff = krealloc(seg->buff, max_bytes, or->alloc_flags);
+        if (!buff) {
+                OSD_ERR("Failed to Realloc %d-bytes was-%d\n", max_bytes,
+                        seg->alloc_size);
+                return -ENOMEM;
+        }
+
+        memset(buff + seg->alloc_size, 0, max_bytes - seg->alloc_size);
+        seg->buff = buff;
+        seg->alloc_size = max_bytes;
+        return 0;
+}
+
+static int _alloc_set_attr_list(struct osd_request *or,
+        const struct osd_attr *oa, unsigned nelem, unsigned add_bytes)
+{
+        unsigned total_bytes = add_bytes;
+
+        for (; nelem; --nelem, ++oa)
+                total_bytes += _osd_req_alist_elem_size(or, oa->len);
+
+        OSD_DEBUG("total_bytes=%d\n", total_bytes);
+        return _osd_realloc_seg(or, &or->set_attr, total_bytes);
+}
+
+static int _alloc_get_attr_desc(struct osd_request *or, unsigned max_bytes)
+{
+        OSD_DEBUG("total_bytes=%d\n", max_bytes);
+        return _osd_realloc_seg(or, &or->enc_get_attr, max_bytes);
+}
+
+static int _alloc_get_attr_list(struct osd_request *or)
+{
+        OSD_DEBUG("total_bytes=%d\n", or->get_attr.total_bytes);
+        return _osd_realloc_seg(or, &or->get_attr, or->get_attr.total_bytes);
+}
+
 /*
  * Common to all OSD commands
  */
@@ -284,6 +395,410 @@ void osd_req_read(struct osd_request *or,
 }
 EXPORT_SYMBOL(osd_req_read);
 
+void osd_req_get_attributes(struct osd_request *or,
+        const struct osd_obj_id *obj)
+{
+        _osd_req_encode_common(or, OSD_ACT_GET_ATTRIBUTES, obj, 0, 0);
+}
+EXPORT_SYMBOL(osd_req_get_attributes);
+
+void osd_req_set_attributes(struct osd_request *or,
+        const struct osd_obj_id *obj)
+{
+        _osd_req_encode_common(or, OSD_ACT_SET_ATTRIBUTES, obj, 0, 0);
+}
+EXPORT_SYMBOL(osd_req_set_attributes);
+
+/*
+ * Attributes List-mode
+ */
+
+int osd_req_add_set_attr_list(struct osd_request *or,
+        const struct osd_attr *oa, unsigned nelem)
+{
+        unsigned total_bytes = or->set_attr.total_bytes;
+        void *attr_last;
+        int ret;
+
+        if (or->attributes_mode &&
+            or->attributes_mode != OSD_CDB_GET_SET_ATTR_LISTS) {
+                WARN_ON(1);
+                return -EINVAL;
+        }
+        or->attributes_mode = OSD_CDB_GET_SET_ATTR_LISTS;
+
+        if (!total_bytes) { /* first-time: allocate and put list header */
+                total_bytes = _osd_req_sizeof_alist_header(or);
+                ret = _alloc_set_attr_list(or, oa, nelem, total_bytes);
+                if (ret)
+                        return ret;
+                _osd_req_set_alist_type(or, or->set_attr.buff,
+                                        OSD_ATTR_LIST_SET_RETRIEVE);
+        }
+        attr_last = or->set_attr.buff + total_bytes;
+
+        for (; nelem; --nelem) {
+                struct osd_attributes_list_element *attr;
+                unsigned elem_size = _osd_req_alist_elem_size(or, oa->len);
+
+                total_bytes += elem_size;
+                if (unlikely(or->set_attr.alloc_size < total_bytes)) {
+                        or->set_attr.total_bytes = total_bytes - elem_size;
+                        ret = _alloc_set_attr_list(or, oa, nelem, total_bytes);
+                        if (ret)
+                                return ret;
+                        attr_last =
+                                or->set_attr.buff + or->set_attr.total_bytes;
+                }
+
+                attr = attr_last;
+                attr->attr_page = cpu_to_be32(oa->attr_page);
+                attr->attr_id = cpu_to_be32(oa->attr_id);
+                attr->attr_bytes = cpu_to_be16(oa->len);
+                memcpy(attr->attr_val, oa->val_ptr, oa->len);
+
+                attr_last += elem_size;
+                ++oa;
+        }
+
+        or->set_attr.total_bytes = total_bytes;
+        return 0;
+}
+EXPORT_SYMBOL(osd_req_add_set_attr_list);
+
+static int _append_map_kern(struct request *req,
+        void *buff, unsigned len, gfp_t flags)
+{
+        struct bio *bio;
+        int ret;
+
+        bio = bio_map_kern(req->q, buff, len, flags);
+        if (IS_ERR(bio)) {
+                OSD_ERR("Failed bio_map_kern(%p, %d) => %ld\n", buff, len,
+                        PTR_ERR(bio));
+                return PTR_ERR(bio);
+        }
+        ret = blk_rq_append_bio(req->q, req, bio);
+        if (ret) {
+                OSD_ERR("Failed blk_rq_append_bio(%p) => %d\n", bio, ret);
+                bio_put(bio);
+        }
+        return ret;
+}
+
+static int _req_append_segment(struct osd_request *or,
+        unsigned padding, struct _osd_req_data_segment *seg,
+        struct _osd_req_data_segment *last_seg, struct _osd_io_info *io)
+{
+        void *pad_buff;
+        int ret;
+
+        if (padding) {
+                /* check if we can just add it to last buffer */
+                if (last_seg &&
+                    (padding <= last_seg->alloc_size - last_seg->total_bytes))
+                        pad_buff = last_seg->buff + last_seg->total_bytes;
+                else
+                        pad_buff = io->pad_buff;
+
+                ret = _append_map_kern(io->req, pad_buff, padding,
+                                       or->alloc_flags);
+                if (ret)
+                        return ret;
+                io->total_bytes += padding;
+        }
+
+        ret = _append_map_kern(io->req, seg->buff, seg->total_bytes,
+                               or->alloc_flags);
+        if (ret)
+                return ret;
+
+        io->total_bytes += seg->total_bytes;
+        OSD_DEBUG("padding=%d buff=%p total_bytes=%d\n", padding, seg->buff,
+                  seg->total_bytes);
+        return 0;
+}
+
+static int _osd_req_finalize_set_attr_list(struct osd_request *or)
+{
+        struct osd_cdb_head *cdbh = osd_cdb_head(&or->cdb);
+        unsigned padding;
+        int ret;
+
+        if (!or->set_attr.total_bytes) {
+                cdbh->attrs_list.set_attr_offset = OSD_OFFSET_UNUSED;
+                return 0;
+        }
+
+        cdbh->attrs_list.set_attr_bytes = cpu_to_be32(or->set_attr.total_bytes);
+        cdbh->attrs_list.set_attr_offset =
+                osd_req_encode_offset(or, or->out.total_bytes, &padding);
+
+        ret = _req_append_segment(or, padding, &or->set_attr,
+                                  or->out.last_seg, &or->out);
+        if (ret)
+                return ret;
+
+        or->out.last_seg = &or->set_attr;
+        return 0;
+}
+
+int osd_req_add_get_attr_list(struct osd_request *or,
+        const struct osd_attr *oa, unsigned nelem)
+{
+        unsigned total_bytes = or->enc_get_attr.total_bytes;
+        void *attr_last;
+        int ret;
+
+        if (or->attributes_mode &&
+            or->attributes_mode != OSD_CDB_GET_SET_ATTR_LISTS) {
+                WARN_ON(1);
+                return -EINVAL;
+        }
+        or->attributes_mode = OSD_CDB_GET_SET_ATTR_LISTS;
+
+        /* first time calc data-in list header size */
+        if (!or->get_attr.total_bytes)
+                or->get_attr.total_bytes = _osd_req_sizeof_alist_header(or);
+
+        /* calc data-out info */
+        if (!total_bytes) { /* first-time: allocate and put list header */
+                unsigned max_bytes;
+
+                total_bytes = _osd_req_sizeof_alist_header(or);
+                max_bytes = total_bytes +
+                        nelem * sizeof(struct osd_attributes_list_attrid);
+                ret = _alloc_get_attr_desc(or, max_bytes);
+                if (ret)
+                        return ret;
+
+                _osd_req_set_alist_type(or, or->enc_get_attr.buff,
+                                        OSD_ATTR_LIST_GET);
+        }
+        attr_last = or->enc_get_attr.buff + total_bytes;
+
+        for (; nelem; --nelem) {
+                struct osd_attributes_list_attrid *attrid;
+                const unsigned cur_size = sizeof(*attrid);
+
+                total_bytes += cur_size;
+                if (unlikely(or->enc_get_attr.alloc_size < total_bytes)) {
+                        or->enc_get_attr.total_bytes = total_bytes - cur_size;
+                        ret = _alloc_get_attr_desc(or,
+                                        total_bytes + nelem * sizeof(*attrid));
+                        if (ret)
+                                return ret;
+                        attr_last = or->enc_get_attr.buff +
+                                or->enc_get_attr.total_bytes;
+                }
+
+                attrid = attr_last;
+                attrid->attr_page = cpu_to_be32(oa->attr_page);
+                attrid->attr_id = cpu_to_be32(oa->attr_id);
+
+                attr_last += cur_size;
+
+                /* calc data-in size */
+                or->get_attr.total_bytes +=
+                        _osd_req_alist_elem_size(or, oa->len);
+                ++oa;
+        }
+
+        or->enc_get_attr.total_bytes = total_bytes;
+
+        OSD_DEBUG(
+               "get_attr.total_bytes=%u(%u) enc_get_attr.total_bytes=%u(%Zu)\n",
+               or->get_attr.total_bytes,
+               or->get_attr.total_bytes - _osd_req_sizeof_alist_header(or),
+               or->enc_get_attr.total_bytes,
+               (or->enc_get_attr.total_bytes - _osd_req_sizeof_alist_header(or))
+                        / sizeof(struct osd_attributes_list_attrid));
+
+        return 0;
+}
+EXPORT_SYMBOL(osd_req_add_get_attr_list);
+
+static int _osd_req_finalize_get_attr_list(struct osd_request *or)
+{
+        struct osd_cdb_head *cdbh = osd_cdb_head(&or->cdb);
+        unsigned out_padding;
+        unsigned in_padding;
+        int ret;
+
+        if (!or->enc_get_attr.total_bytes) {
+                cdbh->attrs_list.get_attr_desc_offset = OSD_OFFSET_UNUSED;
+                cdbh->attrs_list.get_attr_offset = OSD_OFFSET_UNUSED;
+                return 0;
+        }
+
+        ret = _alloc_get_attr_list(or);
+        if (ret)
+                return ret;
+
+        /* The out-going buffer info update */
+        OSD_DEBUG("out-going\n");
+        cdbh->attrs_list.get_attr_desc_bytes =
+                cpu_to_be32(or->enc_get_attr.total_bytes);
+
+        cdbh->attrs_list.get_attr_desc_offset =
+                osd_req_encode_offset(or, or->out.total_bytes, &out_padding);
+
+        ret = _req_append_segment(or, out_padding, &or->enc_get_attr,
+                                  or->out.last_seg, &or->out);
+        if (ret)
+                return ret;
+        or->out.last_seg = &or->enc_get_attr;
+
+        /* The incoming buffer info update */
+        OSD_DEBUG("in-coming\n");
+        cdbh->attrs_list.get_attr_alloc_length =
+                cpu_to_be32(or->get_attr.total_bytes);
+
+        cdbh->attrs_list.get_attr_offset =
+                osd_req_encode_offset(or, or->in.total_bytes, &in_padding);
+
+        ret = _req_append_segment(or, in_padding, &or->get_attr, NULL,
+                                  &or->in);
+        if (ret)
+                return ret;
+        or->in.last_seg = &or->get_attr;
+
+        return 0;
+}
+
+int osd_req_decode_get_attr_list(struct osd_request *or,
+        struct osd_attr *oa, int *nelem, void **iterator)
+{
+        unsigned cur_bytes, returned_bytes;
+        int n;
+        const unsigned sizeof_attr_list = _osd_req_sizeof_alist_header(or);
+        void *cur_p;
+
+        if (!_osd_req_is_alist_type(or, or->get_attr.buff,
+                                    OSD_ATTR_LIST_SET_RETRIEVE)) {
+                oa->attr_page = 0;
+                oa->attr_id = 0;
+                oa->val_ptr = NULL;
+                oa->len = 0;
+                *iterator = NULL;
+                return 0;
+        }
+
+        if (*iterator) {
+                BUG_ON((*iterator < or->get_attr.buff) ||
+                     (or->get_attr.buff + or->get_attr.alloc_size < *iterator));
+                cur_p = *iterator;
+                cur_bytes = (*iterator - or->get_attr.buff) - sizeof_attr_list;
+                returned_bytes = or->get_attr.total_bytes;
+        } else { /* first time decode the list header */
+                cur_bytes = sizeof_attr_list;
+                returned_bytes = _osd_req_alist_size(or, or->get_attr.buff) +
+                                        sizeof_attr_list;
+
+                cur_p = or->get_attr.buff + sizeof_attr_list;
+
+                if (returned_bytes > or->get_attr.alloc_size) {
+                        OSD_DEBUG("target report: space was not big enough! "
+                                  "Allocate=%u Needed=%u\n",
+                                  or->get_attr.alloc_size,
+                                  returned_bytes + sizeof_attr_list);
+
+                        returned_bytes =
+                                or->get_attr.alloc_size - sizeof_attr_list;
+                }
+                or->get_attr.total_bytes = returned_bytes;
+        }
+
+        for (n = 0; (n < *nelem) && (cur_bytes < returned_bytes); ++n) {
+                struct osd_attributes_list_element *attr = cur_p;
+                unsigned inc;
+
+                oa->len = be16_to_cpu(attr->attr_bytes);
+                inc = _osd_req_alist_elem_size(or, oa->len);
+                OSD_DEBUG("oa->len=%d inc=%d cur_bytes=%d\n",
+                          oa->len, inc, cur_bytes);
+                cur_bytes += inc;
+                if (cur_bytes > returned_bytes) {
+                        OSD_ERR("BAD FOOD from target. list not valid!"
+                                "c=%d r=%d n=%d\n",
+                                cur_bytes, returned_bytes, n);
+                        oa->val_ptr = NULL;
+                        break;
+                }
+
+                oa->attr_page = be32_to_cpu(attr->attr_page);
+                oa->attr_id = be32_to_cpu(attr->attr_id);
+                oa->val_ptr = attr->attr_val;
+
+                cur_p += inc;
+                ++oa;
+        }
+
+        *iterator = (returned_bytes - cur_bytes) ? cur_p : NULL;
+        *nelem = n;
+        return returned_bytes - cur_bytes;
+}
+EXPORT_SYMBOL(osd_req_decode_get_attr_list);
+
+/*
+ * Attributes Page-mode
+ */
+
+int osd_req_add_get_attr_page(struct osd_request *or,
+        u32 page_id, void *attar_page, unsigned max_page_len,
+        const struct osd_attr *set_one_attr)
+{
+        struct osd_cdb_head *cdbh = osd_cdb_head(&or->cdb);
+
+        if (or->attributes_mode &&
+            or->attributes_mode != OSD_CDB_GET_ATTR_PAGE_SET_ONE) {
+                WARN_ON(1);
+                return -EINVAL;
+        }
+        or->attributes_mode = OSD_CDB_GET_ATTR_PAGE_SET_ONE;
+
+        or->get_attr.buff = attar_page;
+        or->get_attr.total_bytes = max_page_len;
+
+        or->set_attr.buff = set_one_attr->val_ptr;
+        or->set_attr.total_bytes = set_one_attr->len;
+
+        cdbh->attrs_page.get_attr_page = cpu_to_be32(page_id);
+        cdbh->attrs_page.get_attr_alloc_length = cpu_to_be32(max_page_len);
+        /* ocdb->attrs_page.get_attr_offset; */
+
+        cdbh->attrs_page.set_attr_page = cpu_to_be32(set_one_attr->attr_page);
+        cdbh->attrs_page.set_attr_id = cpu_to_be32(set_one_attr->attr_id);
+        cdbh->attrs_page.set_attr_length = cpu_to_be32(set_one_attr->len);
+        /* ocdb->attrs_page.set_attr_offset; */
+        return 0;
+}
+EXPORT_SYMBOL(osd_req_add_get_attr_page);
+
+static int _osd_req_finalize_attr_page(struct osd_request *or)
+{
+        struct osd_cdb_head *cdbh = osd_cdb_head(&or->cdb);
+        unsigned in_padding, out_padding;
+        int ret;
+
+        /* returned page */
+        cdbh->attrs_page.get_attr_offset =
+                osd_req_encode_offset(or, or->in.total_bytes, &in_padding);
+
+        ret = _req_append_segment(or, in_padding, &or->get_attr, NULL,
+                                  &or->in);
+        if (ret)
+                return ret;
+
+        /* set one value */
+        cdbh->attrs_page.set_attr_offset =
+                osd_req_encode_offset(or, or->out.total_bytes, &out_padding);
+
+        ret = _req_append_segment(or, out_padding, &or->enc_get_attr, NULL,
+                                  &or->out);
+        return ret;
+}
+
 /*
  * osd_finalize_request and helpers
  */
@@ -378,9 +893,31 @@ int osd_finalize_request(struct osd_request *or,
                         _LLU(or->in.total_bytes), or->in.req->data_len);
         }
 
+        or->out.pad_buff = sg_out_pad_buffer;
+        or->in.pad_buff = sg_in_pad_buffer;
+
         if (!or->attributes_mode)
                 or->attributes_mode = OSD_CDB_GET_SET_ATTR_LISTS;
         cdbh->command_specific_options |= or->attributes_mode;
+        if (or->attributes_mode == OSD_CDB_GET_ATTR_PAGE_SET_ONE) {
+                ret = _osd_req_finalize_attr_page(or);
+        } else {
+                /* TODO: I think that for the GET_ATTR command these 2 should
+                 * be reversed to keep them in execution order (for embeded
+                 * targets with low memory footprint)
+                 */
+                ret = _osd_req_finalize_set_attr_list(or);
+                if (ret) {
+                        OSD_DEBUG("_osd_req_finalize_set_attr_list failed\n");
+                        return ret;
+                }
+
+                ret = _osd_req_finalize_get_attr_list(or);
+                if (ret) {
+                        OSD_DEBUG("_osd_req_finalize_get_attr_list failed\n");
+                        return ret;
+                }
+        }
 
         or->request->cmd = or->cdb.buff;
         or->request->cmd_len = _osd_req_cdb_len(or);
@@ -446,3 +983,45 @@ void osd_set_caps(struct osd_cdb *cdb, const void *caps)
 {
         memcpy(&cdb->v1.caps, caps, OSDv1_CAP_LEN);
 }
+
+/*
+ * Declared in osd_protocol.h
+ * 4.12.5 Data-In and Data-Out buffer offsets
+ * byte offset = mantissa * (2^(exponent+8))
+ * Returns the smallest allowed encoded offset that contains given @offset
+ * The actual encoded offset returned is @offset + *@padding.
+ */
+osd_cdb_offset __osd_encode_offset(
+        u64 offset, unsigned *padding, int min_shift, int max_shift)
+{
+        u64 try_offset = -1, mod, align;
+        osd_cdb_offset be32_offset;
+        int shift;
+
+        *padding = 0;
+        if (!offset)
+                return 0;
+
+        for (shift = min_shift; shift < max_shift; ++shift) {
+                try_offset = offset >> shift;
+                if (try_offset < (1 << OSD_OFFSET_MAX_BITS))
+                        break;
+        }
+
+        BUG_ON(shift == max_shift);
+
+        align = 1 << shift;
+        mod = offset & (align - 1);
+        if (mod) {
+                *padding = align - mod;
+                try_offset += 1;
+        }
+
+        try_offset |= ((shift - 8) & 0xf) << 28;
+        be32_offset = cpu_to_be32((u32)try_offset);
+
+        OSD_DEBUG("offset=%llu mantissa=%llu exp=%d encoded=%x pad=%d\n",
+                 _LLU(offset), _LLU(try_offset & 0x0FFFFFFF), shift,
+                 be32_offset, *padding);
+        return be32_offset;
+}