[PATCH 06/24] pnfs: filelayout: clean and breakup nfs4_pnfs_dserver_get

Fred Isaman
2010-06-08T04:19:46Z

Rewrite nfs4_pnfs_dserver_get as two functions, nfs4_fl_calc_ds_index() and
nfs4_fl_prepare_ds(). This cleans up the code a bit and prepares for more
extensive rewrite of filelayout_commit().

Signed-off-by: Fred Isaman <iisaman@netapp.com>
---
fs/nfs/nfs4filelayout.c | 75 ++++++++++++----------------------
fs/nfs/nfs4filelayout.h | 33 +++++++--------
fs/nfs/nfs4filelayoutdev.c | 95 +++++++++++++++----------------------------
3 files changed, 75 insertions(+), 128 deletions(-)

diff --git a/fs/nfs/nfs4filelayout.c b/fs/nfs/nfs4filelayout.c
index b0cda5d..2ffca74 100644
--- a/fs/nfs/nfs4filelayout.c
+++ b/fs/nfs/nfs4filelayout.c
@@ -196,8 +196,8 @@ filelayout_read_pagelist(struct pnfs_layout_type *layoutid,
{
struct inode *inode = PNFS_INODE(layoutid);
struct nfs4_filelayout_segment *flseg;
- struct nfs4_pnfs_dserver dserver;
- int status;
+ struct nfs4_pnfs_ds *ds;
+ u32 idx;

dprintk("--> %s ino %lu nr_pages %d pgbase %u req %Zu@%llu\n",
__func__, inode->i_ino, nr_pages, pgbase, count, offset);
@@ -205,23 +205,19 @@ filelayout_read_pagelist(struct pnfs_layout_type *layoutid,
flseg = LSEG_LD_DATA(data->pdata.lseg);

/* Retrieve the correct rpc_client for the byte range */
- status = nfs4_pnfs_dserver_get(data->pdata.lseg,
- offset,
- count,
- &dserver);
- if (status) {
- printk(KERN_ERR "%s: dserver get failed status %d use MDS\n",
- __func__, status);
+ idx = nfs4_fl_calc_ds_index(data->pdata.lseg, offset);
+ ds = nfs4_fl_prepare_ds(data->pdata.lseg, idx);
+ if (!ds) {
+ printk(KERN_ERR "%s: prepare_ds failed, use MDS\n", __func__);
return PNFS_NOT_ATTEMPTED;
}
-
dprintk("%s USE DS:ip %x %s\n", __func__,
- htonl(dserver.ds->ds_ip_addr), dserver.ds->r_addr);
+ htonl(ds->ds_ip_addr), ds->r_addr);

/* just try the first data server for the index..*/
- data->fldata.pnfs_client = dserver.ds->ds_clp->cl_rpcclient;
- data->fldata.ds_nfs_client = dserver.ds->ds_clp;
- data->args.fh = dserver.fh;
+ data->fldata.ds_nfs_client = ds->ds_clp;
+ data->fldata.pnfs_client = ds->ds_clp->cl_rpcclient;
+ data->args.fh = nfs4_fl_select_ds_fh(flseg, idx);

/* Now get the file offset on the dserver
* Set the read offset to this offset, and
@@ -255,32 +251,26 @@ filelayout_write_pagelist(struct pnfs_layout_type *layoutid,
{
struct inode *inode = PNFS_INODE(layoutid);
struct nfs4_filelayout_segment *flseg = LSEG_LD_DATA(data->pdata.lseg);
- struct nfs4_pnfs_dserver dserver;
- int status;
+ struct nfs4_pnfs_ds *ds;
+ u32 idx;

dprintk("--> %s ino %lu nr_pages %d pgbase %u req %Zu@%llu sync %d\n",
__func__, inode->i_ino, nr_pages, pgbase, count, offset, sync);

/* Retrieve the correct rpc_client for the byte range */
- status = nfs4_pnfs_dserver_get(data->pdata.lseg,
- offset,
- count,
- &dserver);
-
- if (status) {
- printk(KERN_ERR "%s: dserver get failed status %d use MDS\n",
- __func__, status);
+ idx = nfs4_fl_calc_ds_index(data->pdata.lseg, offset);
+ ds = nfs4_fl_prepare_ds(data->pdata.lseg, idx);
+ if (!ds) {
+ printk(KERN_ERR "%s: prepare_ds failed, use MDS\n", __func__);
return PNFS_NOT_ATTEMPTED;
}
-
dprintk("%s ino %lu %Zu@%llu DS:%x:%hu %s\n",
__func__, inode->i_ino, count, offset,
- htonl(dserver.ds->ds_ip_addr), ntohs(dserver.ds->ds_port),
- dserver.ds->r_addr);
+ htonl(ds->ds_ip_addr), ntohs(ds->ds_port), ds->r_addr);

- data->fldata.pnfs_client = dserver.ds->ds_clp->cl_rpcclient;
- data->fldata.ds_nfs_client = dserver.ds->ds_clp;
- data->args.fh = dserver.fh;
+ data->fldata.ds_nfs_client = ds->ds_clp;
+ data->fldata.pnfs_client = ds->ds_clp->cl_rpcclient;
+ data->args.fh = nfs4_fl_select_ds_fh(flseg, idx);

/* Get the file offset on the dserver. Set the write offset to
* this offset and save the original offset.
@@ -568,15 +558,12 @@ filelayout_commit(struct pnfs_layout_type *layoutid, int sync,
{
struct nfs4_filelayout_segment *nfslay;
struct nfs_write_data *dsdata = NULL;
- struct nfs4_pnfs_dserver dserver;
struct nfs4_pnfs_ds *ds;
struct nfs_page *req, *reqt;
struct list_head *pos, *tmp, head, head2;
loff_t file_offset, comp_offset;
size_t stripesz, cbytes;
- int status;
enum pnfs_try_status trypnfs = PNFS_ATTEMPTED;
- struct nfs4_file_layout_dsaddr *dsaddr;
u32 idx1, idx2;

nfslay = LSEG_LD_DATA(data->pdata.lseg);
@@ -593,9 +580,6 @@ filelayout_commit(struct pnfs_layout_type *layoutid, int sync,
stripesz = filelayout_get_stripesize(layoutid);
dprintk("%s stripesize %Zd\n", __func__, stripesz);

- dsaddr = container_of(data->pdata.lseg->deviceid,
- struct nfs4_file_layout_dsaddr, deviceid);
-
INIT_LIST_HEAD(&head);
INIT_LIST_HEAD(&head2);
list_add(&head, &data->pages);
@@ -609,19 +593,13 @@ filelayout_commit(struct pnfs_layout_type *layoutid, int sync,
file_offset = (loff_t)req->wb_index << PAGE_CACHE_SHIFT;

/* Get dserver for the current page */
- status = nfs4_pnfs_dserver_get(data->pdata.lseg,
- file_offset,
- req->wb_bytes,
- &dserver);
- if (status) {
+ idx1 = nfs4_fl_calc_ds_index(data->pdata.lseg, file_offset);
+ ds = nfs4_fl_prepare_ds(data->pdata.lseg, idx1);
+ if (!ds) {
data->pdata.pnfs_error = -EIO;
goto err_rewind;
}

- /* Get its index */
- idx1 = filelayout_dserver_get_index(file_offset, dsaddr,
- nfslay);
-
/* Gather all pages going to the current data server by
* comparing their indices.
* XXX: This recalculates the indices unecessarily.
@@ -630,8 +608,8 @@ filelayout_commit(struct pnfs_layout_type *layoutid, int sync,
list_for_each_safe(pos, tmp, &head) {
reqt = nfs_list_entry(pos);
comp_offset = (loff_t)reqt->wb_index << PAGE_CACHE_SHIFT;
- idx2 = filelayout_dserver_get_index(comp_offset,
- dsaddr, nfslay);
+ idx2 = nfs4_fl_calc_ds_index(data->pdata.lseg,
+ comp_offset);
if (idx1 == idx2) {
nfs_list_remove_request(reqt);
nfs_list_add_request(reqt, &head2);
@@ -655,10 +633,9 @@ filelayout_commit(struct pnfs_layout_type *layoutid, int sync,
list_add(&dsdata->pages, &head2);
list_del_init(&head2);

- ds = dserver.ds;
dsdata->fldata.pnfs_client = ds->ds_clp->cl_rpcclient;
dsdata->fldata.ds_nfs_client = ds->ds_clp;
- dsdata->args.fh = dserver.fh;
+ dsdata->args.fh = nfs4_fl_select_ds_fh(nfslay, idx1);

dprintk("%s: Initiating commit: %Zu@%llu USE DS:\n",
__func__, cbytes, file_offset);
diff --git a/fs/nfs/nfs4filelayout.h b/fs/nfs/nfs4filelayout.h
index fbf307c..3697926 100644
--- a/fs/nfs/nfs4filelayout.h
+++ b/fs/nfs/nfs4filelayout.h
@@ -26,6 +26,9 @@

#define FILE_MT(inode) ((struct filelayout_mount_type *) \
(NFS_SERVER(inode)->pnfs_mountid->mountid))
+#define FILE_DSADDR(lseg) (container_of(lseg->deviceid, \
+ struct nfs4_file_layout_dsaddr, \
+ deviceid))

enum stripetype4 {
STRIPE_SPARSE = 1,
@@ -55,16 +58,6 @@ struct nfs4_pnfs_dev_hlist {
struct hlist_head dev_list[NFS4_PNFS_DEV_HASH_SIZE];
};

-/*
- * Used for I/O, Maps a stripe index to a layout file handle and a
- * multipath data server.
- */
-
-struct nfs4_pnfs_dserver {
- struct nfs_fh *fh;
- struct nfs4_pnfs_ds *ds;
-};
-
struct nfs4_filelayout_segment {
u32 stripe_type;
u32 commit_through_mds;
@@ -87,18 +80,24 @@ struct filelayout_mount_type {
struct super_block *fl_sb;
};

+static inline struct nfs_fh *
+nfs4_fl_select_ds_fh(struct nfs4_filelayout_segment *flseg, u32 idx)
+{
+ /* FRED - what about case == 0??? */
+ if (flseg->num_fh == 1)
+ return &flseg->fh_array[0];
+ else
+ return &flseg->fh_array[idx];
+}
+
extern struct pnfs_client_operations *pnfs_callback_ops;

extern void nfs4_fl_free_deviceid_callback(struct kref *);
extern void print_ds(struct nfs4_pnfs_ds *ds);
char *deviceid_fmt(const struct pnfs_deviceid *dev_id);
-int nfs4_pnfs_dserver_get(struct pnfs_layout_segment *lseg,
- loff_t offset,
- size_t count,
- struct nfs4_pnfs_dserver *dserver);
-u32 filelayout_dserver_get_index(loff_t offset,
- struct nfs4_file_layout_dsaddr *di,
- struct nfs4_filelayout_segment *layout);
+u32 nfs4_fl_calc_ds_index(struct pnfs_layout_segment *lseg, loff_t offset);
+struct nfs4_pnfs_ds *nfs4_fl_prepare_ds(struct pnfs_layout_segment *lseg,
+ u32 ds_idx);
extern struct nfs4_file_layout_dsaddr *
nfs4_pnfs_device_item_find(struct nfs_client *, struct pnfs_deviceid *dev_id);
struct nfs4_file_layout_dsaddr *
diff --git a/fs/nfs/nfs4filelayoutdev.c b/fs/nfs/nfs4filelayoutdev.c
index f5eb5f1..404dd5f 100644
--- a/fs/nfs/nfs4filelayoutdev.c
+++ b/fs/nfs/nfs4filelayoutdev.c
@@ -554,90 +554,61 @@ nfs4_pnfs_device_item_find(struct nfs_client *clp, struct pnfs_deviceid *id)
container_of(d, struct nfs4_file_layout_dsaddr, deviceid);
}

-/* Want res = ((offset / layout->stripe_unit) % dsaddr->stripe_count)
+/* Want res = (offset - layout->pattern_offset)/ layout->stripe_unit
* Then: ((res + fsi) % dsaddr->stripe_count)
*/
-u32
-filelayout_dserver_get_index(loff_t offset,
- struct nfs4_file_layout_dsaddr *dsaddr,
- struct nfs4_filelayout_segment *layout)
+static inline u32
+_nfs4_fl_calc_j_index(loff_t offset,
+ struct nfs4_file_layout_dsaddr *dsaddr,
+ struct nfs4_filelayout_segment *layout)
{
- u64 tmp, tmp2;
+ u64 tmp;

- tmp = offset;
+ tmp = offset - layout->pattern_offset;
do_div(tmp, layout->stripe_unit);
- tmp2 = do_div(tmp, dsaddr->stripe_count) + layout->first_stripe_index;
- return do_div(tmp2, dsaddr->stripe_count);
+ tmp += layout->first_stripe_index;
+ return do_div(tmp, dsaddr->stripe_count);
}

-/* Retrieve the rpc client for a specified byte range
- * in 'inode' by filling in the contents of 'dserver'.
- */
-int
-nfs4_pnfs_dserver_get(struct pnfs_layout_segment *lseg,
- loff_t offset,
- size_t count,
- struct nfs4_pnfs_dserver *dserver)
+u32
+nfs4_fl_calc_ds_index(struct pnfs_layout_segment *lseg, loff_t offset)
{
- struct nfs4_filelayout_segment *layout = LSEG_LD_DATA(lseg);
- struct inode *inode = PNFS_INODE(lseg->layout);
- struct nfs_server *mds_srv = NFS_SERVER(inode);
+ struct nfs4_filelayout_segment *flseg = LSEG_LD_DATA(lseg);
struct nfs4_file_layout_dsaddr *dsaddr;
- u64 tmp, tmp2;
- u32 stripe_idx, end_idx, ds_idx;
-
- if (!layout)
- return 1;
-
- dsaddr = container_of(lseg->deviceid, struct nfs4_file_layout_dsaddr,
- deviceid);
-
- stripe_idx = filelayout_dserver_get_index(offset, dsaddr, layout);
-
- /* For debugging, ensure entire requested range is in this dserver */
- tmp = offset + count - 1;
- do_div(tmp, layout->stripe_unit);
- tmp2 = do_div(tmp, dsaddr->stripe_count) + layout->first_stripe_index;
- end_idx = do_div(tmp2, dsaddr->stripe_count);
+ u32 j;

- dprintk("%s: offset=%Lu, count=%Zu, si=%u, dsi=%u, "
- "stripe_count=%u, stripe_unit=%u first_stripe_index %u\n",
- __func__,
- offset, count, stripe_idx, end_idx, dsaddr->stripe_count,
- layout->stripe_unit, layout->first_stripe_index);
+ dsaddr = FILE_DSADDR(lseg);
+ j = _nfs4_fl_calc_j_index(offset, dsaddr, flseg);
+ return dsaddr->stripe_indices[j];
+}

- BUG_ON(end_idx != stripe_idx);
- BUG_ON(stripe_idx >= dsaddr->stripe_count);
+struct nfs4_pnfs_ds *
+nfs4_fl_prepare_ds(struct pnfs_layout_segment *lseg, u32 ds_idx)
+{
+ struct nfs4_filelayout_segment *flseg = LSEG_LD_DATA(lseg);
+ struct nfs4_file_layout_dsaddr *dsaddr;

- ds_idx = dsaddr->stripe_indices[stripe_idx];
+ dsaddr = FILE_DSADDR(lseg);
if (dsaddr->ds_list[ds_idx] == NULL) {
- printk(KERN_ERR "%s: No data server for device id (%s)!! \n",
- __func__, deviceid_fmt(&layout->dev_id));
- return 1;
+ printk(KERN_ERR "%s: No data server for device id (%s)!!\n",
+ __func__, deviceid_fmt(&flseg->dev_id));
+ return NULL;
}

if (!dsaddr->ds_list[ds_idx]->ds_clp) {
int err;

- err = nfs4_pnfs_ds_create(mds_srv, dsaddr->ds_list[ds_idx]);
+ err = nfs4_pnfs_ds_create(PNFS_NFS_SERVER(lseg->layout),
+ dsaddr->ds_list[ds_idx]);
if (err) {
printk(KERN_ERR "%s nfs4_pnfs_ds_create error %d\n",
__func__, err);
- return 1;
+ return NULL;
}
}
- dserver->ds = dsaddr->ds_list[ds_idx];
+ dprintk("%s: dev_id=%s, ds_idx=%u\n",
+ __func__, deviceid_fmt(&flseg->dev_id), ds_idx);

- if (layout->num_fh == 1)
- dserver->fh = &layout->fh_array[0];
- else
- dserver->fh = &layout->fh_array[ds_idx];
-
- dprintk("%s: dev_id=%s, ip:port=%s, ds_idx=%u stripe_idx=%u, "
- "offset=%llu, count=%Zu\n",
- __func__, deviceid_fmt(&layout->dev_id),
- dserver->ds->r_addr,
- ds_idx, stripe_idx, offset, count);
-
- return 0;
+ return dsaddr->ds_list[ds_idx];
}
+
--
1.6.6.1