diff options
| -rw-r--r-- | tests/basic/uss.t | 22 | ||||
| -rw-r--r-- | xlators/features/snapview-server/src/snapview-server.c | 160 | ||||
| -rw-r--r-- | xlators/features/snapview-server/src/snapview-server.h | 29 |
3 files changed, 177 insertions, 34 deletions
diff --git a/tests/basic/uss.t b/tests/basic/uss.t index f97cd59883e..04d4baf64a5 100644 --- a/tests/basic/uss.t +++ b/tests/basic/uss.t @@ -101,20 +101,31 @@ TEST fd_close $fd3 # test 44 TEST mount_nfs $H0:/$V0 $N0 nolock; -TEST ls -l $N0/.snaps; - NUM_SNAPS=$(ls $N0/.snaps | wc -l); TEST [ $NUM_SNAPS == 4 ]; +TEST stat $N0/.snaps/snap1; +TEST stat $N0/.snaps/snap2; + +TEST ls -l $N0/.snaps; + +# readdir + lookup on each entry TEST ls -l $N0/.snaps/snap1; TEST ls -l $N0/.snaps/snap2; -TEST ls -l $N0/.snaps/snap3; -TEST ls -l $N0/.snaps/snap4; + +# readdir + access each entry by doing stat. If snapview-server has not +# filled the fs instance and handle in the inode context of the entry as +# part of readdirp, then when stat comes (i.e fop comes directly without +# a previous lookup), snapview-server should do a lookup of the entry via +# gfapi call and fill in the fs instance + handle information in the inode +# context +TEST ls $N0/.snaps/snap3/; +TEST stat $N0/.snaps/snap3/dir1; +TEST stat $N0/.snaps/snap3/dir2; TEST ls -l $N0/.snaps/snap3/dir1; TEST ls -l $N0/.snaps/snap3/dir2; - TEST ls -l $N0/.snaps/snap4/dir1; TEST ls -l $N0/.snaps/snap4/dir2; @@ -123,6 +134,7 @@ TEST ! ls -l $N0/dir2/.snaps/snap2; TEST ls -l $N0/dir1/.snaps/snap3; TEST ls -l $N0/dir2/.snaps/snap4; + TEST fd1=`fd_available` TEST fd_open $fd1 'r' $N0/.snaps/snap1/file1; TEST fd_cat $fd1 diff --git a/xlators/features/snapview-server/src/snapview-server.c b/xlators/features/snapview-server/src/snapview-server.c index 21f3dbee563..a9c95850f3e 100644 --- a/xlators/features/snapview-server/src/snapview-server.c +++ b/xlators/features/snapview-server/src/snapview-server.c @@ -575,8 +575,10 @@ svs_opendir (call_frame_t *frame, xlator_t *this, loc_t *loc, fd_t *fd, op_errno = 0; goto out; } else if (inode_ctx->type == SNAP_VIEW_VIRTUAL_INODE) { - fs = inode_ctx->fs; - object = inode_ctx->object; + + SVS_GET_INODE_CTX_INFO(inode_ctx, fs, object, this, loc, op_ret, + op_errno, out); + glfd = glfs_h_opendir (fs, object); if (!glfd) { op_ret = -1; @@ -701,8 +703,10 @@ svs_getxattr (call_frame_t *frame, xlator_t *this, loc_t *loc, const char *name, op_errno = EINVAL; goto out; } else if (inode_ctx->type == SNAP_VIEW_VIRTUAL_INODE) { - fs = inode_ctx->fs; - object = inode_ctx->object; + + SVS_GET_INODE_CTX_INFO(inode_ctx, fs, object, this, loc, op_ret, + op_errno, out); + dict = dict_new (); if (!dict) { gf_log (this->name, GF_LOG_ERROR, "failed to " @@ -1439,6 +1443,118 @@ unwind: return 0; } +/* + * This function is mainly helpful for NFS. Till now NFS server was not linking + * the inodes in readdirp, which caused problems when below operations were + * performed. + * + * 1) ls -l in one of the snaopshots (snapview-server would generate gfids for + * each entry on the fly and link the inodes associated with those entries) + * 2) NFS server upon getting readdirp reply would not link the inodes of the + * entries. But it used to generate filehandles for each entry and associate + * the gfid of that entry with the filehandle and send it as part of the + * reply to nfs client. + * 3) NFS client would send the filehandle of one of those entries when some + * activity is done on it. + * 4) NFS server would not be able to find the inode for the gfid present in the + * filehandle (as the inode was not linked) and would go for hard resolution + * by sending a lookup on the gfid by creating a new inode. + * 5) snapview-client will not able to identify whether the inode is a real + * inode existing in the main volume or a virtual inode existing in the + * snapshots as there would not be any inode context. + * 6) Since the gfid upon which lookup is sent is a virtual gfid which is not + * present in the disk, lookup would fail and the application would get an + * error. + * + * The above problem is fixed by the below commit which makes snapview server + * more compatible with nfs server (1dea949cb60c3814c9206df6ba8dddec8d471a94). + * But now because NFS server does inode linking in readdirp has introduced + * the below issue. + * In readdirp though snapview-server allocates inode contexts it does not + * actually perform lookup on each entry it obtained in readdirp (as doing + * a lookup via gfapi over the network for each entry would be costly). + * + * Till now it was not a problem with NFS server, as NFS was sending a lookup on + * the gfid it got from NFS client, for which it was not able to find the right + * inode. So snapview-server was able to get the fs instance (glfs_t) of the + * snapshot volume to which the entry belongs to, and the handle for the entry + * from the corresponding snapshot volume and fill those informations in the + * inode context. + * + * But now, since NFS server is able to find the inode from the inode table for + * the gfid it got from the NFS client, it wont send lookup. Rather it directly + * sends the fop it received from the client. Now this causes problems for + * snapview-server. Because for each fop snapview-server assumes that lookup has + * been performed on that entry and the entry's inode context contains the + * pointers for the fs instance and the handle to the entry in that fs. When NFS + * server sends the fop and snapview-server finds that the fs instance and the + * handle within the inode context are NULL it unwinds with EINVAL. + * + * So to handle this, if fs instance or handle within the inode context are + * NULL, then do a lookup based on parent inode context's fs instance. And + * unwind the results obtained as part of lookup + */ + +int32_t +svs_get_handle (xlator_t *this, loc_t *loc, svs_inode_t *inode_ctx, + int32_t *op_errno) +{ + svs_inode_t *parent_ctx = NULL; + int ret = -1; + inode_t *parent = NULL; + struct iatt postparent = {0, }; + struct iatt buf = {0, }; + char uuid1[64]; + + GF_VALIDATE_OR_GOTO ("snap-view-daemon", this, out); + GF_VALIDATE_OR_GOTO (this->name, loc, out); + GF_VALIDATE_OR_GOTO (this->name, loc->inode, out); + + if (loc->path) { + if (!loc->name || (loc->name && !strcmp (loc->name, ""))) { + loc->name = strrchr (loc->path, '/'); + if (loc->name) + loc->name++; + } + } + + if (loc->parent) + parent = inode_ref (loc->parent); + else { + parent = inode_find (loc->inode->table, loc->pargfid); + if (!parent) + parent = inode_parent (loc->inode, NULL, NULL); + } + + if (parent) + parent_ctx = svs_inode_ctx_get (this, parent); + + if (!parent_ctx) { + gf_log (this->name, GF_LOG_WARNING, "failed to get the parent " + "context for %s (%s)", loc->path, + uuid_utoa_r (loc->inode->gfid, uuid1)); + *op_errno = EINVAL; + goto out; + } + + if (parent_ctx) { + if (parent_ctx->type == SNAP_VIEW_ENTRY_POINT_INODE) + ret = svs_lookup_snapshot (this, loc, &buf, + &postparent, parent, + parent_ctx, op_errno); + else + ret = svs_lookup_entry (this, loc, &buf, + &postparent, parent, + parent_ctx, op_errno); + } + +out: + if (parent) + inode_unref (parent); + + return ret; +} + int32_t svs_stat (call_frame_t *frame, xlator_t *this, loc_t *loc, dict_t *xdata) { @@ -1477,8 +1593,10 @@ svs_stat (call_frame_t *frame, xlator_t *this, loc_t *loc, dict_t *xdata) svs_iatt_fill (loc->inode->gfid, &buf); op_ret = 0; } else if (inode_ctx->type == SNAP_VIEW_VIRTUAL_INODE) { - fs = inode_ctx->fs; - object = inode_ctx->object; + + SVS_GET_INODE_CTX_INFO(inode_ctx, fs, object, this, loc, op_ret, + op_errno, out); + ret = glfs_h_stat (fs, object, &stat); if (ret) { gf_log (this->name, GF_LOG_ERROR, "glfs_h_stat on %s " @@ -1599,8 +1717,8 @@ svs_open (call_frame_t *frame, xlator_t *this, loc_t *loc, int32_t flags, if (inode_ctx->type == SNAP_VIEW_ENTRY_POINT_INODE) GF_ASSERT (0); // on entry point it should always be opendir - fs = inode_ctx->fs; - object = inode_ctx->object; + SVS_GET_INODE_CTX_INFO(inode_ctx, fs, object, this, loc, op_ret, + op_errno, out); glfd = glfs_h_open (fs, object, flags); if (!glfd) { @@ -1749,25 +1867,8 @@ svs_readlink (call_frame_t *frame, xlator_t *this, goto out; } - fs = inode_ctx->fs; - if (!fs) { - gf_log (this->name, GF_LOG_ERROR, "failed to get the fs " - "instance for %s (gfid: %s)", loc->name, - uuid_utoa (loc->inode->gfid)); - op_ret = -1; - op_errno = ESTALE; - goto out; - } - - object = inode_ctx->object; - if (!object) { - gf_log (this->name, GF_LOG_ERROR, "failed to get the object " - "for %s (gfid: %s)", loc->name, - uuid_utoa (loc->inode->gfid)); - op_ret = -1; - op_errno = ESTALE; - goto out; - } + SVS_GET_INODE_CTX_INFO(inode_ctx, fs, object, this, loc, op_ret, + op_errno, out); ret = glfs_h_stat (fs, object, &stat); if (ret) { @@ -1850,8 +1951,9 @@ svs_access (call_frame_t *frame, xlator_t *this, loc_t *loc, int mask, goto out; } - fs = inode_ctx->fs; - object = inode_ctx->object; + + SVS_GET_INODE_CTX_INFO(inode_ctx, fs, object, this, loc, op_ret, + op_errno, out); /* The actual posix_acl xlator does acl checks differently for fuse and nfs. So set frame->root->pid as fspid of the syncop diff --git a/xlators/features/snapview-server/src/snapview-server.h b/xlators/features/snapview-server/src/snapview-server.h index e689e4981a0..4b42aefcd98 100644 --- a/xlators/features/snapview-server/src/snapview-server.h +++ b/xlators/features/snapview-server/src/snapview-server.h @@ -53,6 +53,31 @@ STACK_DESTROY (((call_frame_t *)_frame)->root); \ } while (0) +#define SVS_GET_INODE_CTX_INFO(inode_ctx, fs, object, this, loc, ret, \ + op_errno, label) \ + do { \ + fs = inode_ctx->fs; \ + object = inode_ctx->object; \ + if (!fs || !object) { \ + int32_t tmp = -1; \ + char tmp_uuid[64]; \ + \ + tmp = svs_get_handle (this, loc, inode_ctx, \ + &op_errno); \ + if (tmp) { \ + gf_log (this->name, GF_LOG_ERROR, \ + "failed to get the handle for %s " \ + "(gfid: %s)", loc->path, \ + uuid_utoa_r (loc->inode->gfid, \ + tmp_uuid)); \ + ret = -1; \ + goto label; \ + } \ + \ + fs = inode_ctx->fs; \ + object = inode_ctx->object; \ + } \ + } while(0); int svs_mgmt_submit_request (void *req, call_frame_t *frame, @@ -168,4 +193,8 @@ svs_get_snap_dirent (xlator_t *this, const char *name); int svs_mgmt_init (xlator_t *this); +int32_t +svs_get_handle (xlator_t *this, loc_t *loc, svs_inode_t *inode_ctx, + int32_t *op_errno); + #endif /* __SNAP_VIEW_H__ */ |