staging: lustre: lov: refactor lov_object_fiemap()
authorBobi Jam <bobijam.xu@intel.com>
Wed, 26 Jul 2017 15:37:59 +0000 (11:37 -0400)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sun, 30 Jul 2017 15:04:11 +0000 (08:04 -0700)
Add fiemap_for_stripe() to get file map extent from each stripe
device.

Signed-off-by: Bobi Jam <bobijam.xu@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-8773
Reviewed-on: https://review.whamcloud.com/23461
Reviewed-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Jinshan Xiong <jinshan.xiong@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>
Signed-off-by: James Simmons <jsimmons@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/staging/lustre/lustre/lov/lov_object.c

index 8365e7ab73f0cdb1eb77c7fc591a791d7cb3722e..a33955aabbc54326fd3be6fb6addd451e49c9004 100644 (file)
@@ -1126,6 +1126,190 @@ static u64 fiemap_calc_fm_end_offset(struct fiemap *fiemap,
        return fm_end_offset;
 }
 
+struct fiemap_state {
+       struct fiemap   *fs_fm;
+       u64             fs_start;
+       u64             fs_length;
+       u64             fs_end;
+       u64             fs_end_offset;
+       int             fs_cur_extent;
+       int             fs_cnt_need;
+       int             fs_start_stripe;
+       int             fs_last_stripe;
+       bool            fs_device_done;
+       bool            fs_finish;
+       bool            fs_enough;
+};
+
+int fiemap_for_stripe(const struct lu_env *env, struct cl_object *obj,
+                     struct lov_stripe_md *lsm,
+                     struct fiemap *fiemap, size_t *buflen,
+                     struct ll_fiemap_info_key *fmkey, int stripeno,
+                     struct fiemap_state *fs)
+{
+       struct cl_object *subobj;
+       struct lov_obd *lov = lu2lov_dev(obj->co_lu.lo_dev)->ld_lov;
+       struct fiemap_extent *fm_ext = &fs->fs_fm->fm_extents[0];
+       u64 req_fm_len; /* Stores length of required mapping */
+       u64 len_mapped_single_call;
+       u64 lun_start;
+       u64 lun_end;
+       u64 obd_object_end;
+       unsigned int ext_count;
+       /* EOF for object */
+       bool ost_eof = false;
+       /* done with required mapping for this OST? */
+       bool ost_done = false;
+       int ost_index;
+       int rc = 0;
+
+       fs->fs_device_done = false;
+       /* Find out range of mapping on this stripe */
+       if ((lov_stripe_intersects(lsm, stripeno, fs->fs_start, fs->fs_end,
+                                  &lun_start, &obd_object_end)) == 0)
+               return 0;
+
+       if (lov_oinfo_is_dummy(lsm->lsm_oinfo[stripeno]))
+               return -EIO;
+
+       /* If this is a continuation FIEMAP call and we are on
+        * starting stripe then lun_start needs to be set to
+        * end_offset */
+       if (fs->fs_end_offset != 0 && stripeno == fs->fs_start_stripe)
+               lun_start = fs->fs_end_offset;
+
+       lun_end = fs->fs_length;
+       if (lun_end != ~0ULL) {
+               /* Handle fs->fs_start + fs->fs_length overflow */
+               if (fs->fs_start + fs->fs_length < fs->fs_start)
+                       fs->fs_length = ~0ULL - fs->fs_start;
+               lun_end = lov_size_to_stripe(lsm, fs->fs_start + fs->fs_length,
+                                            stripeno);
+       }
+
+       if (lun_start == lun_end)
+               return 0;
+
+       req_fm_len = obd_object_end - lun_start;
+       fs->fs_fm->fm_length = 0;
+       len_mapped_single_call = 0;
+
+       /* find lobsub object */
+       subobj = lov_find_subobj(env, cl2lov(obj), lsm, stripeno);
+       if (IS_ERR(subobj))
+               return PTR_ERR(subobj);
+       /* If the output buffer is very large and the objects have many
+        * extents we may need to loop on a single OST repeatedly */
+       do {
+               if (fiemap->fm_extent_count > 0) {
+                       /* Don't get too many extents. */
+                       if (fs->fs_cur_extent + fs->fs_cnt_need >
+                           fiemap->fm_extent_count)
+                               fs->fs_cnt_need = fiemap->fm_extent_count -
+                                                 fs->fs_cur_extent;
+               }
+
+               lun_start += len_mapped_single_call;
+               fs->fs_fm->fm_length = req_fm_len - len_mapped_single_call;
+               req_fm_len = fs->fs_fm->fm_length;
+               fs->fs_fm->fm_extent_count = fs->fs_enough ?
+                                            1 : fs->fs_cnt_need;
+               fs->fs_fm->fm_mapped_extents = 0;
+               fs->fs_fm->fm_flags = fiemap->fm_flags;
+
+               ost_index = lsm->lsm_oinfo[stripeno]->loi_ost_idx;
+
+               if (ost_index < 0 || ost_index >= lov->desc.ld_tgt_count) {
+                       rc = -EINVAL;
+                       goto obj_put;
+               }
+               /* If OST is inactive, return extent with UNKNOWN flag. */
+               if (!lov->lov_tgts[ost_index]->ltd_active) {
+                       fs->fs_fm->fm_flags |= FIEMAP_EXTENT_LAST;
+                       fs->fs_fm->fm_mapped_extents = 1;
+
+                       fm_ext[0].fe_logical = lun_start;
+                       fm_ext[0].fe_length = obd_object_end - lun_start;
+                       fm_ext[0].fe_flags |= FIEMAP_EXTENT_UNKNOWN;
+
+                       goto inactive_tgt;
+               }
+
+               fs->fs_fm->fm_start = lun_start;
+               fs->fs_fm->fm_flags &= ~FIEMAP_FLAG_DEVICE_ORDER;
+               memcpy(&fmkey->lfik_fiemap, fs->fs_fm, sizeof(*fs->fs_fm));
+               *buflen = fiemap_count_to_size(fs->fs_fm->fm_extent_count);
+
+               rc = cl_object_fiemap(env, subobj, fmkey, fs->fs_fm, buflen);
+               if (rc)
+                       goto obj_put;
+inactive_tgt:
+               ext_count = fs->fs_fm->fm_mapped_extents;
+               if (ext_count == 0) {
+                       ost_done = true;
+                       fs->fs_device_done = true;
+                       /* If last stripe has hold at the end,
+                        * we need to return */
+                       if (stripeno == fs->fs_last_stripe) {
+                               fiemap->fm_mapped_extents = 0;
+                               fs->fs_finish = true;
+                               goto obj_put;
+                       }
+                       break;
+               } else if (fs->fs_enough) {
+                       /*
+                        * We've collected enough extents and there are
+                        * more extents after it.
+                        */
+                       fs->fs_finish = true;
+                       goto obj_put;
+               }
+
+               /* If we just need num of extents, got to next device */
+               if (fiemap->fm_extent_count == 0) {
+                       fs->fs_cur_extent += ext_count;
+                       break;
+               }
+
+               /* prepare to copy retrived map extents */
+               len_mapped_single_call = fm_ext[ext_count - 1].fe_logical +
+                                        fm_ext[ext_count - 1].fe_length -
+                                        lun_start;
+
+               /* Have we finished mapping on this device? */
+               if (req_fm_len <= len_mapped_single_call) {
+                       ost_done = true;
+                       fs->fs_device_done = true;
+               }
+
+               /* Clear the EXTENT_LAST flag which can be present on
+                * the last extent */
+               if (fm_ext[ext_count - 1].fe_flags & FIEMAP_EXTENT_LAST)
+                       fm_ext[ext_count - 1].fe_flags &= ~FIEMAP_EXTENT_LAST;
+               if (lov_stripe_size(lsm, fm_ext[ext_count - 1].fe_logical +
+                                        fm_ext[ext_count - 1].fe_length,
+                                   stripeno) >= fmkey->lfik_oa.o_size) {
+                       ost_eof = true;
+                       fs->fs_device_done = true;
+               }
+
+               fiemap_prepare_and_copy_exts(fiemap, fm_ext, ost_index,
+                                            ext_count, fs->fs_cur_extent);
+               fs->fs_cur_extent += ext_count;
+
+               /* Ran out of available extents? */
+               if (fs->fs_cur_extent >= fiemap->fm_extent_count)
+                       fs->fs_enough = true;
+       } while (!ost_done && !ost_eof);
+
+       if (stripeno == fs->fs_last_stripe)
+               fs->fs_finish = true;
+obj_put:
+       cl_object_put(env, subobj);
+
+       return rc;
+}
+
 /**
  * Break down the FIEMAP request and send appropriate calls to individual OSTs.
  * This also handles the restarting of FIEMAP calls in case mapping overflows
@@ -1144,31 +1328,13 @@ static int lov_object_fiemap(const struct lu_env *env, struct cl_object *obj,
                             struct ll_fiemap_info_key *fmkey,
                             struct fiemap *fiemap, size_t *buflen)
 {
-       struct lov_obd *lov = lu2lov_dev(obj->co_lu.lo_dev)->ld_lov;
        unsigned int buffer_size = FIEMAP_BUFFER_SIZE;
-       struct fiemap_extent *lcl_fm_ext;
-       struct cl_object *subobj = NULL;
        struct fiemap *fm_local = NULL;
        struct lov_stripe_md *lsm;
-       u64 fm_start;
-       u64 fm_end;
-       u64 fm_length;
-       u64 fm_end_offset;
-       int count_local;
-       int ost_index = 0;
-       int start_stripe;
-       int current_extent = 0;
        int rc = 0;
-       int last_stripe;
-       int cur_stripe = 0;
-       int cur_stripe_wrap = 0;
+       int cur_stripe;
        int stripe_count;
-       /* Whether have we collected enough extents */
-       bool enough = false;
-       /* EOF for object */
-       bool ost_eof = false;
-       /* done with required mapping for this OST? */
-       bool ost_done = false;
+       struct fiemap_state fs = { 0 };
 
        lsm = lov_lsm_addref(cl2lov(obj));
        if (!lsm)
@@ -1215,28 +1381,37 @@ static int lov_object_fiemap(const struct lu_env *env, struct cl_object *obj,
                rc = -ENOMEM;
                goto out;
        }
-       lcl_fm_ext = &fm_local->fm_extents[0];
-       count_local = fiemap_size_to_count(buffer_size);
+       fs.fs_fm = fm_local;
+       fs.fs_cnt_need = fiemap_size_to_count(buffer_size);
 
-       fm_start = fiemap->fm_start;
-       fm_length = fiemap->fm_length;
+       fs.fs_start = fiemap->fm_start;
+       /* fs_start is beyond the end of the file */
+       if (fs.fs_start > fmkey->lfik_oa.o_size) {
+               rc = -EINVAL;
+               goto out;
+       }
        /* Calculate start stripe, last stripe and length of mapping */
-       start_stripe = lov_stripe_number(lsm, fm_start);
-       fm_end = (fm_length == ~0ULL) ? fmkey->lfik_oa.o_size :
-                                       fm_start + fm_length - 1;
-       /* If fm_length != ~0ULL but fm_start_fm_length-1 exceeds file size */
-       if (fm_end > fmkey->lfik_oa.o_size)
-               fm_end = fmkey->lfik_oa.o_size;
-
-       last_stripe = fiemap_calc_last_stripe(lsm, fm_start, fm_end,
-                                             start_stripe, &stripe_count);
-       fm_end_offset = fiemap_calc_fm_end_offset(fiemap, lsm, fm_start, fm_end,
-                                                 &start_stripe);
-       if (fm_end_offset == -EINVAL) {
+       fs.fs_start_stripe = lov_stripe_number(lsm, fs.fs_start);
+       fs.fs_end = (fs.fs_length == ~0ULL) ? fmkey->lfik_oa.o_size :
+                                             fs.fs_start + fs.fs_length - 1;
+       /* If fs_length != ~0ULL but fs_start+fs_length-1 exceeds file size */
+       if (fs.fs_end > fmkey->lfik_oa.o_size) {
+               fs.fs_end = fmkey->lfik_oa.o_size;
+               fs.fs_length = fs.fs_end - fs.fs_start;
+       }
+
+       fs.fs_last_stripe = fiemap_calc_last_stripe(lsm, fs.fs_start, fs.fs_end,
+                                                   fs.fs_start_stripe,
+                                                   &stripe_count);
+       fs.fs_end_offset = fiemap_calc_fm_end_offset(fiemap, lsm, fs.fs_start,
+                                                    fs.fs_end,
+                                                    &fs.fs_start_stripe);
+       if (fs.fs_end_offset == -EINVAL) {
                rc = -EINVAL;
                goto out;
        }
 
+
        /**
         * Requested extent count exceeds the fiemap buffer size, shrink our
         * ambition.
@@ -1244,186 +1419,23 @@ static int lov_object_fiemap(const struct lu_env *env, struct cl_object *obj,
        if (fiemap_count_to_size(fiemap->fm_extent_count) > *buflen)
                fiemap->fm_extent_count = fiemap_size_to_count(*buflen);
        if (!fiemap->fm_extent_count)
-               count_local = 0;
+               fs.fs_cnt_need = 0;
+
+       fs.fs_finish = false;
+       fs.fs_enough = false;
+       fs.fs_cur_extent = 0;
 
        /* Check each stripe */
-       for (cur_stripe = start_stripe; stripe_count > 0;
+       for (cur_stripe = fs.fs_start_stripe; stripe_count > 0;
             --stripe_count,
             cur_stripe = (cur_stripe + 1) % lsm->lsm_stripe_count) {
-               u64 req_fm_len; /* Stores length of required mapping */
-               u64 len_mapped_single_call;
-               u64 lun_start;
-               u64 lun_end;
-               u64 obd_object_end;
-               unsigned int ext_count;
-
-               cur_stripe_wrap = cur_stripe;
-
-               /* Find out range of mapping on this stripe */
-               if (!(lov_stripe_intersects(lsm, cur_stripe, fm_start, fm_end,
-                                           &lun_start, &obd_object_end)))
-                       continue;
-
-               if (lov_oinfo_is_dummy(lsm->lsm_oinfo[cur_stripe])) {
-                       rc = -EIO;
-                       goto out;
-               }
-
-               /*
-                * If this is a continuation FIEMAP call and we are on
-                * starting stripe then lun_start needs to be set to
-                * fm_end_offset
-                */
-               if (fm_end_offset && cur_stripe == start_stripe)
-                       lun_start = fm_end_offset;
-
-               if (fm_length != ~0ULL) {
-                       /* Handle fm_start + fm_length overflow */
-                       if (fm_start + fm_length < fm_start)
-                               fm_length = ~0ULL - fm_start;
-                       lun_end = lov_size_to_stripe(lsm, fm_start + fm_length,
-                                                    cur_stripe);
-               } else {
-                       lun_end = ~0ULL;
-               }
-
-               if (lun_start == lun_end)
-                       continue;
-
-               req_fm_len = obd_object_end - lun_start;
-               fm_local->fm_length = 0;
-               len_mapped_single_call = 0;
-
-               /* find lobsub object */
-               subobj = lov_find_subobj(env, cl2lov(obj), lsm,
-                                        cur_stripe);
-               if (IS_ERR(subobj)) {
-                       rc = PTR_ERR(subobj);
+               rc = fiemap_for_stripe(env, obj, lsm, fiemap, buflen, fmkey,
+                                      cur_stripe, &fs);
+               if (rc < 0)
                        goto out;
-               }
-               /*
-                * If the output buffer is very large and the objects have many
-                * extents we may need to loop on a single OST repeatedly
-                */
-               ost_eof = false;
-               ost_done = false;
-               do {
-                       if (fiemap->fm_extent_count > 0) {
-                               /* Don't get too many extents. */
-                               if (current_extent + count_local >
-                                   fiemap->fm_extent_count)
-                                       count_local = fiemap->fm_extent_count -
-                                                     current_extent;
-                       }
-
-                       lun_start += len_mapped_single_call;
-                       fm_local->fm_length = req_fm_len -
-                                             len_mapped_single_call;
-                       req_fm_len = fm_local->fm_length;
-                       fm_local->fm_extent_count = enough ? 1 : count_local;
-                       fm_local->fm_mapped_extents = 0;
-                       fm_local->fm_flags = fiemap->fm_flags;
-
-                       ost_index = lsm->lsm_oinfo[cur_stripe]->loi_ost_idx;
-
-                       if (ost_index < 0 ||
-                           ost_index >= lov->desc.ld_tgt_count) {
-                               rc = -EINVAL;
-                               goto obj_put;
-                       }
-                       /*
-                        * If OST is inactive, return extent with UNKNOWN
-                        * flag.
-                        */
-                       if (!lov->lov_tgts[ost_index]->ltd_active) {
-                               fm_local->fm_flags |= FIEMAP_EXTENT_LAST;
-                               fm_local->fm_mapped_extents = 1;
-
-                               lcl_fm_ext[0].fe_logical = lun_start;
-                               lcl_fm_ext[0].fe_length = obd_object_end -
-                                                         lun_start;
-                               lcl_fm_ext[0].fe_flags |= FIEMAP_EXTENT_UNKNOWN;
-
-                               goto inactive_tgt;
-                       }
-
-                       fm_local->fm_start = lun_start;
-                       fm_local->fm_flags &= ~FIEMAP_FLAG_DEVICE_ORDER;
-                       memcpy(&fmkey->lfik_fiemap, fm_local, sizeof(*fm_local));
-                       *buflen = fiemap_count_to_size(fm_local->fm_extent_count);
-
-                       rc = cl_object_fiemap(env, subobj, fmkey, fm_local,
-                                             buflen);
-                       if (rc)
-                               goto obj_put;
-inactive_tgt:
-                       ext_count = fm_local->fm_mapped_extents;
-                       if (!ext_count) {
-                               ost_done = true;
-                               /*
-                                * If last stripe has hold at the end,
-                                * we need to return
-                                */
-                               if (cur_stripe_wrap == last_stripe) {
-                                       fiemap->fm_mapped_extents = 0;
-                                       goto finish;
-                               }
-                               break;
-                       } else if (enough) {
-                               /*
-                                * We've collected enough extents and there are
-                                * more extents after it.
-                                */
-                               goto finish;
-                       }
-
-                       /* If we just need num of extents, got to next device */
-                       if (!fiemap->fm_extent_count) {
-                               current_extent += ext_count;
-                               break;
-                       }
-
-                       /* prepare to copy retrived map extents */
-                       len_mapped_single_call =
-                               lcl_fm_ext[ext_count - 1].fe_logical -
-                               lun_start + lcl_fm_ext[ext_count - 1].fe_length;
-
-                       /* Have we finished mapping on this device? */
-                       if (req_fm_len <= len_mapped_single_call)
-                               ost_done = true;
-
-                       /*
-                        * Clear the EXTENT_LAST flag which can be present on
-                        * the last extent
-                        */
-                       if (lcl_fm_ext[ext_count - 1].fe_flags &
-                           FIEMAP_EXTENT_LAST)
-                               lcl_fm_ext[ext_count - 1].fe_flags &=
-                                       ~FIEMAP_EXTENT_LAST;
-
-                       if (lov_stripe_size(lsm,
-                                           lcl_fm_ext[ext_count - 1].fe_logical +
-                                           lcl_fm_ext[ext_count - 1].fe_length,
-                                           cur_stripe) >= fmkey->lfik_oa.o_size)
-                               ost_eof = true;
-
-                       fiemap_prepare_and_copy_exts(fiemap, lcl_fm_ext,
-                                                    ost_index, ext_count,
-                                                    current_extent);
-                       current_extent += ext_count;
-
-                       /* Ran out of available extents? */
-                       if (current_extent >= fiemap->fm_extent_count)
-                               enough = true;
-               } while (!ost_done && !ost_eof);
-
-               cl_object_put(env, subobj);
-               subobj = NULL;
-
-               if (cur_stripe_wrap == last_stripe)
-                       goto finish;
+               if (fs.fs_finish)
+                       break;
        } /* for each stripe */
-finish:
        /*
         * Indicate that we are returning device offsets unless file just has
         * single stripe
@@ -1438,14 +1450,11 @@ finish:
         * Check if we have reached the last stripe and whether mapping for that
         * stripe is done.
         */
-       if ((cur_stripe_wrap == last_stripe) && (ost_done || ost_eof))
-               fiemap->fm_extents[current_extent - 1].fe_flags |=
+       if ((cur_stripe == fs.fs_last_stripe) && fs.fs_device_done)
+               fiemap->fm_extents[fs.fs_cur_extent - 1].fe_flags |=
                                                        FIEMAP_EXTENT_LAST;
 skip_last_device_calc:
-       fiemap->fm_mapped_extents = current_extent;
-obj_put:
-       if (subobj)
-               cl_object_put(env, subobj);
+       fiemap->fm_mapped_extents = fs.fs_cur_extent;
 out:
        kvfree(fm_local);
        lov_lsm_put(lsm);