--- /dev/null
+/*
+ * linux/fs/nfs/blocklayout/blocklayout.c
+ *
+ * Module for the NFSv4.1 pNFS block layout driver.
+ *
+ * Copyright (c) 2006 The Regents of the University of Michigan.
+ * All rights reserved.
+ *
+ * Andy Adamson <andros@citi.umich.edu>
+ * Fred Isaman <iisaman@umich.edu>
+ *
+ * permission is granted to use, copy, create derivative works and
+ * redistribute this software and such derivative works for any purpose,
+ * so long as the name of the university of michigan is not used in
+ * any advertising or publicity pertaining to the use or distribution
+ * of this software without specific, written prior authorization. if
+ * the above copyright notice or any other identification of the
+ * university of michigan is included in any copy of any portion of
+ * this software, then the disclaimer below must also be included.
+ *
+ * this software is provided as is, without representation from the
+ * university of michigan as to its fitness for any purpose, and without
+ * warranty by the university of michigan of any kind, either express
+ * or implied, including without limitation the implied warranties of
+ * merchantability and fitness for a particular purpose. the regents
+ * of the university of michigan shall not be liable for any damages,
+ * including special, indirect, incidental, or consequential damages,
+ * with respect to any claim arising out or in connection with the use
+ * of the software, even if it has been or is hereafter advised of the
+ * possibility of such damages.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/mount.h>
+#include <linux/namei.h>
+#include <linux/bio.h> /* struct bio */
+#include <linux/prefetch.h>
+#include <linux/pagevec.h>
+
+#include "../pnfs.h"
+#include "../nfs4session.h"
+#include "../internal.h"
+#include "blocklayout.h"
+
+#define NFSDBG_FACILITY NFSDBG_PNFS_LD
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Andy Adamson <andros@citi.umich.edu>");
+MODULE_DESCRIPTION("The NFSv4.1 pNFS Block layout driver");
+
+static bool is_hole(struct pnfs_block_extent *be)
+{
+ switch (be->be_state) {
+ case PNFS_BLOCK_NONE_DATA:
+ return true;
+ case PNFS_BLOCK_INVALID_DATA:
+ return be->be_tag ? false : true;
+ default:
+ return false;
+ }
+}
+
+/* The data we are handed might be spread across several bios. We need
+ * to track when the last one is finished.
+ */
+struct parallel_io {
+ struct kref refcnt;
+ void (*pnfs_callback) (void *data);
+ void *data;
+};
+
+static inline struct parallel_io *alloc_parallel(void *data)
+{
+ struct parallel_io *rv;
+
+ rv = kmalloc(sizeof(*rv), GFP_NOFS);
+ if (rv) {
+ rv->data = data;
+ kref_init(&rv->refcnt);
+ }
+ return rv;
+}
+
+static inline void get_parallel(struct parallel_io *p)
+{
+ kref_get(&p->refcnt);
+}
+
+static void destroy_parallel(struct kref *kref)
+{
+ struct parallel_io *p = container_of(kref, struct parallel_io, refcnt);
+
+ dprintk("%s enter\n", __func__);
+ p->pnfs_callback(p->data);
+ kfree(p);
+}
+
+static inline void put_parallel(struct parallel_io *p)
+{
+ kref_put(&p->refcnt, destroy_parallel);
+}
+
+static struct bio *
+bl_submit_bio(int rw, struct bio *bio)
+{
+ if (bio) {
+ get_parallel(bio->bi_private);
+ dprintk("%s submitting %s bio %u@%llu\n", __func__,
+ rw == READ ? "read" : "write", bio->bi_iter.bi_size,
+ (unsigned long long)bio->bi_iter.bi_sector);
+ submit_bio(rw, bio);
+ }
+ return NULL;
+}
+
+static struct bio *
+bl_alloc_init_bio(int npg, struct block_device *bdev, sector_t disk_sector,
+ void (*end_io)(struct bio *, int err), struct parallel_io *par)
+{
+ struct bio *bio;
+
+ npg = min(npg, BIO_MAX_PAGES);
+ bio = bio_alloc(GFP_NOIO, npg);
+ if (!bio && (current->flags & PF_MEMALLOC)) {
+ while (!bio && (npg /= 2))
+ bio = bio_alloc(GFP_NOIO, npg);
+ }
+
+ if (bio) {
+ bio->bi_iter.bi_sector = disk_sector;
+ bio->bi_bdev = bdev;
+ bio->bi_end_io = end_io;
+ bio->bi_private = par;
+ }
+ return bio;
+}
+
+static struct bio *
+do_add_page_to_bio(struct bio *bio, int npg, int rw, sector_t isect,
+ struct page *page, struct pnfs_block_dev_map *map,
+ struct pnfs_block_extent *be,
+ void (*end_io)(struct bio *, int err),
+ struct parallel_io *par, unsigned int offset, int *len)
+{
+ struct pnfs_block_dev *dev =
+ container_of(be->be_device, struct pnfs_block_dev, node);
+ u64 disk_addr, end;
+
+ dprintk("%s: npg %d rw %d isect %llu offset %u len %d\n", __func__,
+ npg, rw, (unsigned long long)isect, offset, *len);
+
+ /* translate to device offset */
+ isect += be->be_v_offset;
+ isect -= be->be_f_offset;
+
+ /* translate to physical disk offset */
+ disk_addr = (u64)isect << SECTOR_SHIFT;
+ if (disk_addr < map->start || disk_addr >= map->start + map->len) {
+ if (!dev->map(dev, disk_addr, map))
+ return ERR_PTR(-EIO);
+ bio = bl_submit_bio(rw, bio);
+ }
+ disk_addr += map->disk_offset;
+ disk_addr -= map->start;
+
+ /* limit length to what the device mapping allows */
+ end = disk_addr + *len;
+ if (end >= map->start + map->len)
+ *len = map->start + map->len - disk_addr;
+
+retry:
+ if (!bio) {
+ bio = bl_alloc_init_bio(npg, map->bdev,
+ disk_addr >> SECTOR_SHIFT, end_io, par);
+ if (!bio)
+ return ERR_PTR(-ENOMEM);
+ }
+ if (bio_add_page(bio, page, *len, offset) < *len) {
+ bio = bl_submit_bio(rw, bio);
+ goto retry;
+ }
+ return bio;
+}
+
+static void bl_end_io_read(struct bio *bio, int err)
+{
+ struct parallel_io *par = bio->bi_private;
+
+ if (err) {
+ struct nfs_pgio_header *header = par->data;
+
+ if (!header->pnfs_error)
+ header->pnfs_error = -EIO;
+ pnfs_set_lo_fail(header->lseg);
+ }
+
+ bio_put(bio);
+ put_parallel(par);
+}
+
+static void bl_read_cleanup(struct work_struct *work)
+{
+ struct rpc_task *task;
+ struct nfs_pgio_header *hdr;
+ dprintk("%s enter\n", __func__);
+ task = container_of(work, struct rpc_task, u.tk_work);
+ hdr = container_of(task, struct nfs_pgio_header, task);
+ pnfs_ld_read_done(hdr);
+}
+
+static void
+bl_end_par_io_read(void *data)
+{
+ struct nfs_pgio_header *hdr = data;
+
+ hdr->task.tk_status = hdr->pnfs_error;
+ INIT_WORK(&hdr->task.u.tk_work, bl_read_cleanup);
+ schedule_work(&hdr->task.u.tk_work);
+}
+
+static enum pnfs_try_status
+bl_read_pagelist(struct nfs_pgio_header *header)
+{
+ struct pnfs_block_layout *bl = BLK_LSEG2EXT(header->lseg);
+ struct pnfs_block_dev_map map = { .start = NFS4_MAX_UINT64 };
+ struct bio *bio = NULL;
+ struct pnfs_block_extent be;
+ sector_t isect, extent_length = 0;
+ struct parallel_io *par;
+ loff_t f_offset = header->args.offset;
+ size_t bytes_left = header->args.count;
+ unsigned int pg_offset, pg_len;
+ struct page **pages = header->args.pages;
+ int pg_index = header->args.pgbase >> PAGE_CACHE_SHIFT;
+ const bool is_dio = (header->dreq != NULL);
+ struct blk_plug plug;
+ int i;
+
+ dprintk("%s enter nr_pages %u offset %lld count %u\n", __func__,
+ header->page_array.npages, f_offset,
+ (unsigned int)header->args.count);
+
+ par = alloc_parallel(header);
+ if (!par)
+ return PNFS_NOT_ATTEMPTED;
+ par->pnfs_callback = bl_end_par_io_read;
+
+ blk_start_plug(&plug);
+
+ isect = (sector_t) (f_offset >> SECTOR_SHIFT);
+ /* Code assumes extents are page-aligned */
+ for (i = pg_index; i < header->page_array.npages; i++) {
+ if (extent_length <= 0) {
+ /* We've used up the previous extent */
+ bio = bl_submit_bio(READ, bio);
+
+ /* Get the next one */
+ if (!ext_tree_lookup(bl, isect, &be, false)) {
+ header->pnfs_error = -EIO;
+ goto out;
+ }
+ extent_length = be.be_length - (isect - be.be_f_offset);
+ }
+
+ pg_offset = f_offset & ~PAGE_CACHE_MASK;
+ if (is_dio) {
+ if (pg_offset + bytes_left > PAGE_CACHE_SIZE)
+ pg_len = PAGE_CACHE_SIZE - pg_offset;
+ else
+ pg_len = bytes_left;
+ } else {
+ BUG_ON(pg_offset != 0);
+ pg_len = PAGE_CACHE_SIZE;
+ }
+
+ isect += (pg_offset >> SECTOR_SHIFT);
+ extent_length -= (pg_offset >> SECTOR_SHIFT);
+
+ if (is_hole(&be)) {
+ bio = bl_submit_bio(READ, bio);
+ /* Fill hole w/ zeroes w/o accessing device */
+ dprintk("%s Zeroing page for hole\n", __func__);
+ zero_user_segment(pages[i], pg_offset, pg_len);
+
+ /* invalidate map */
+ map.start = NFS4_MAX_UINT64;
+ } else {
+ bio = do_add_page_to_bio(bio,
+ header->page_array.npages - i,
+ READ,
+ isect, pages[i], &map, &be,
+ bl_end_io_read, par,
+ pg_offset, &pg_len);
+ if (IS_ERR(bio)) {
+ header->pnfs_error = PTR_ERR(bio);
+ bio = NULL;
+ goto out;
+ }
+ }
+ isect += (pg_len >> SECTOR_SHIFT);
+ extent_length -= (pg_len >> SECTOR_SHIFT);
+ f_offset += pg_len;
+ bytes_left -= pg_len;
+ }
+ if ((isect << SECTOR_SHIFT) >= header->inode->i_size) {
+ header->res.eof = 1;
+ header->res.count = header->inode->i_size - header->args.offset;
+ } else {
+ header->res.count = (isect << SECTOR_SHIFT) - header->args.offset;
+ }
+out:
+ bl_submit_bio(READ, bio);
+ blk_finish_plug(&plug);
+ put_parallel(par);
+ return PNFS_ATTEMPTED;
+}
+
+static void bl_end_io_write(struct bio *bio, int err)
+{
+ struct parallel_io *par = bio->bi_private;
+ const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
+ struct nfs_pgio_header *header = par->data;
+
+ if (!uptodate) {
+ if (!header->pnfs_error)
+ header->pnfs_error = -EIO;
+ pnfs_set_lo_fail(header->lseg);
+ }
+ bio_put(bio);
+ put_parallel(par);
+}
+
+/* Function scheduled for call during bl_end_par_io_write,
+ * it marks sectors as written and extends the commitlist.
+ */
+static void bl_write_cleanup(struct work_struct *work)
+{
+ struct rpc_task *task = container_of(work, struct rpc_task, u.tk_work);
+ struct nfs_pgio_header *hdr =
+ container_of(task, struct nfs_pgio_header, task);
+
+ dprintk("%s enter\n", __func__);
+
+ if (likely(!hdr->pnfs_error)) {
+ struct pnfs_block_layout *bl = BLK_LSEG2EXT(hdr->lseg);
+ u64 start = hdr->args.offset & (loff_t)PAGE_CACHE_MASK;
+ u64 end = (hdr->args.offset + hdr->args.count +
+ PAGE_CACHE_SIZE - 1) & (loff_t)PAGE_CACHE_MASK;
+
+ ext_tree_mark_written(bl, start >> SECTOR_SHIFT,
+ (end - start) >> SECTOR_SHIFT);
+ }
+
+ pnfs_ld_write_done(hdr);
+}
+
+/* Called when last of bios associated with a bl_write_pagelist call finishes */
+static void bl_end_par_io_write(void *data)
+{
+ struct nfs_pgio_header *hdr = data;
+
+ hdr->task.tk_status = hdr->pnfs_error;
+ hdr->verf.committed = NFS_FILE_SYNC;
+ INIT_WORK(&hdr->task.u.tk_work, bl_write_cleanup);
+ schedule_work(&hdr->task.u.tk_work);
+}
+
+static enum pnfs_try_status
+bl_write_pagelist(struct nfs_pgio_header *header, int sync)
+{
+ struct pnfs_block_layout *bl = BLK_LSEG2EXT(header->lseg);
+ struct pnfs_block_dev_map map = { .start = NFS4_MAX_UINT64 };
+ struct bio *bio = NULL;
+ struct pnfs_block_extent be;
+ sector_t isect, extent_length = 0;
+ struct parallel_io *par = NULL;
+ loff_t offset = header->args.offset;
+ size_t count = header->args.count;
+ struct page **pages = header->args.pages;
+ int pg_index = header->args.pgbase >> PAGE_CACHE_SHIFT;
+ unsigned int pg_len;
+ struct blk_plug plug;
+ int i;
+
+ dprintk("%s enter, %Zu@%lld\n", __func__, count, offset);
+
+ /* At this point, header->page_aray is a (sequential) list of nfs_pages.
+ * We want to write each, and if there is an error set pnfs_error
+ * to have it redone using nfs.
+ */
+ par = alloc_parallel(header);
+ if (!par)
+ return PNFS_NOT_ATTEMPTED;
+ par->pnfs_callback = bl_end_par_io_write;
+
+ blk_start_plug(&plug);
+
+ /* we always write out the whole page */
+ offset = offset & (loff_t)PAGE_CACHE_MASK;
+ isect = offset >> SECTOR_SHIFT;
+
+ for (i = pg_index; i < header->page_array.npages; i++) {
+ if (extent_length <= 0) {
+ /* We've used up the previous extent */
+ bio = bl_submit_bio(WRITE, bio);
+ /* Get the next one */
+ if (!ext_tree_lookup(bl, isect, &be, true)) {
+ header->pnfs_error = -EINVAL;
+ goto out;
+ }
+
+ extent_length = be.be_length - (isect - be.be_f_offset);
+ }
+
+ pg_len = PAGE_CACHE_SIZE;
+ bio = do_add_page_to_bio(bio, header->page_array.npages - i,
+ WRITE, isect, pages[i], &map, &be,
+ bl_end_io_write, par,
+ 0, &pg_len);
+ if (IS_ERR(bio)) {
+ header->pnfs_error = PTR_ERR(bio);
+ bio = NULL;
+ goto out;
+ }
+
+ offset += pg_len;
+ count -= pg_len;
+ isect += (pg_len >> SECTOR_SHIFT);
+ extent_length -= (pg_len >> SECTOR_SHIFT);
+ }
+
+ header->res.count = header->args.count;
+out:
+ bl_submit_bio(WRITE, bio);
+ blk_finish_plug(&plug);
+ put_parallel(par);
+ return PNFS_ATTEMPTED;
+}
+
+static void bl_free_layout_hdr(struct pnfs_layout_hdr *lo)
+{
+ struct pnfs_block_layout *bl = BLK_LO2EXT(lo);
+ int err;
+
+ dprintk("%s enter\n", __func__);
+
+ err = ext_tree_remove(bl, true, 0, LLONG_MAX);
+ WARN_ON(err);
+
+ kfree(bl);
+}
+
+static struct pnfs_layout_hdr *bl_alloc_layout_hdr(struct inode *inode,
+ gfp_t gfp_flags)
+{
+ struct pnfs_block_layout *bl;
+
+ dprintk("%s enter\n", __func__);
+ bl = kzalloc(sizeof(*bl), gfp_flags);
+ if (!bl)
+ return NULL;
+
+ bl->bl_ext_rw = RB_ROOT;
+ bl->bl_ext_ro = RB_ROOT;
+ spin_lock_init(&bl->bl_ext_lock);
+
+ return &bl->bl_layout;
+}
+
+static void bl_free_lseg(struct pnfs_layout_segment *lseg)
+{
+ dprintk("%s enter\n", __func__);
+ kfree(lseg);
+}
+
+/* Tracks info needed to ensure extents in layout obey constraints of spec */
+struct layout_verification {
+ u32 mode; /* R or RW */
+ u64 start; /* Expected start of next non-COW extent */
+ u64 inval; /* Start of INVAL coverage */
+ u64 cowread; /* End of COW read coverage */
+};
+
+/* Verify the extent meets the layout requirements of the pnfs-block draft,
+ * section 2.3.1.
+ */
+static int verify_extent(struct pnfs_block_extent *be,
+ struct layout_verification *lv)
+{
+ if (lv->mode == IOMODE_READ) {
+ if (be->be_state == PNFS_BLOCK_READWRITE_DATA ||
+ be->be_state == PNFS_BLOCK_INVALID_DATA)
+ return -EIO;
+ if (be->be_f_offset != lv->start)
+ return -EIO;
+ lv->start += be->be_length;
+ return 0;
+ }
+ /* lv->mode == IOMODE_RW */
+ if (be->be_state == PNFS_BLOCK_READWRITE_DATA) {
+ if (be->be_f_offset != lv->start)
+ return -EIO;
+ if (lv->cowread > lv->start)
+ return -EIO;
+ lv->start += be->be_length;
+ lv->inval = lv->start;
+ return 0;
+ } else if (be->be_state == PNFS_BLOCK_INVALID_DATA) {
+ if (be->be_f_offset != lv->start)
+ return -EIO;
+ lv->start += be->be_length;
+ return 0;
+ } else if (be->be_state == PNFS_BLOCK_READ_DATA) {
+ if (be->be_f_offset > lv->start)
+ return -EIO;
+ if (be->be_f_offset < lv->inval)
+ return -EIO;
+ if (be->be_f_offset < lv->cowread)
+ return -EIO;
+ /* It looks like you might want to min this with lv->start,
+ * but you really don't.
+ */
+ lv->inval = lv->inval + be->be_length;
+ lv->cowread = be->be_f_offset + be->be_length;
+ return 0;
+ } else
+ return -EIO;
+}
+
+static int decode_sector_number(__be32 **rp, sector_t *sp)
+{
+ uint64_t s;
+
+ *rp = xdr_decode_hyper(*rp, &s);
+ if (s & 0x1ff) {
+ printk(KERN_WARNING "NFS: %s: sector not aligned\n", __func__);
+ return -1;
+ }
+ *sp = s >> SECTOR_SHIFT;
+ return 0;
+}
+
+static int
+bl_alloc_extent(struct xdr_stream *xdr, struct pnfs_layout_hdr *lo,
+ struct layout_verification *lv, struct list_head *extents,
+ gfp_t gfp_mask)
+{
+ struct pnfs_block_extent *be;
+ struct nfs4_deviceid id;
+ int error;
+ __be32 *p;
+
+ p = xdr_inline_decode(xdr, 28 + NFS4_DEVICEID4_SIZE);
+ if (!p)
+ return -EIO;
+
+ be = kzalloc(sizeof(*be), GFP_NOFS);
+ if (!be)
+ return -ENOMEM;
+
+ memcpy(&id, p, NFS4_DEVICEID4_SIZE);
+ p += XDR_QUADLEN(NFS4_DEVICEID4_SIZE);
+
+ error = -EIO;
+ be->be_device = nfs4_find_get_deviceid(NFS_SERVER(lo->plh_inode), &id,
+ lo->plh_lc_cred, gfp_mask);
+ if (!be->be_device)
+ goto out_free_be;
+
+ /*
+ * The next three values are read in as bytes, but stored in the
+ * extent structure in 512-byte granularity.
+ */
+ if (decode_sector_number(&p, &be->be_f_offset) < 0)
+ goto out_put_deviceid;
+ if (decode_sector_number(&p, &be->be_length) < 0)
+ goto out_put_deviceid;
+ if (decode_sector_number(&p, &be->be_v_offset) < 0)
+ goto out_put_deviceid;
+ be->be_state = be32_to_cpup(p++);
+
+ error = verify_extent(be, lv);
+ if (error) {
+ dprintk("%s: extent verification failed\n", __func__);
+ goto out_put_deviceid;
+ }
+
+ list_add_tail(&be->be_list, extents);
+ return 0;
+
+out_put_deviceid:
+ nfs4_put_deviceid_node(be->be_device);
+out_free_be:
+ kfree(be);
+ return error;
+}
+
+static struct pnfs_layout_segment *
+bl_alloc_lseg(struct pnfs_layout_hdr *lo, struct nfs4_layoutget_res *lgr,
+ gfp_t gfp_mask)
+{
+ struct layout_verification lv = {
+ .mode = lgr->range.iomode,
+ .start = lgr->range.offset >> SECTOR_SHIFT,
+ .inval = lgr->range.offset >> SECTOR_SHIFT,
+ .cowread = lgr->range.offset >> SECTOR_SHIFT,
+ };
+ struct pnfs_block_layout *bl = BLK_LO2EXT(lo);
+ struct pnfs_layout_segment *lseg;
+ struct xdr_buf buf;
+ struct xdr_stream xdr;
+ struct page *scratch;
+ int status, i;
+ uint32_t count;
+ __be32 *p;
+ LIST_HEAD(extents);
+
+ dprintk("---> %s\n", __func__);
+
+ lseg = kzalloc(sizeof(*lseg), gfp_mask);
+ if (!lseg)
+ return ERR_PTR(-ENOMEM);
+
+ status = -ENOMEM;
+ scratch = alloc_page(gfp_mask);
+ if (!scratch)
+ goto out;
+
+ xdr_init_decode_pages(&xdr, &buf,
+ lgr->layoutp->pages, lgr->layoutp->len);
+ xdr_set_scratch_buffer(&xdr, page_address(scratch), PAGE_SIZE);
+
+ status = -EIO;
+ p = xdr_inline_decode(&xdr, 4);
+ if (unlikely(!p))
+ goto out_free_scratch;
+
+ count = be32_to_cpup(p++);
+ dprintk("%s: number of extents %d\n", __func__, count);
+
+ /*
+ * Decode individual extents, putting them in temporary staging area
+ * until whole layout is decoded to make error recovery easier.
+ */
+ for (i = 0; i < count; i++) {
+ status = bl_alloc_extent(&xdr, lo, &lv, &extents, gfp_mask);
+ if (status)
+ goto process_extents;
+ }
+
+ if (lgr->range.offset + lgr->range.length !=
+ lv.start << SECTOR_SHIFT) {
+ dprintk("%s Final length mismatch\n", __func__);
+ status = -EIO;
+ goto process_extents;
+ }
+
+ if (lv.start < lv.cowread) {
+ dprintk("%s Final uncovered COW extent\n", __func__);
+ status = -EIO;
+ }
+
+process_extents:
+ while (!list_empty(&extents)) {
+ struct pnfs_block_extent *be =
+ list_first_entry(&extents, struct pnfs_block_extent,
+ be_list);
+ list_del(&be->be_list);
+
+ if (!status)
+ status = ext_tree_insert(bl, be);
+
+ if (status) {
+ nfs4_put_deviceid_node(be->be_device);
+ kfree(be);
+ }
+ }
+
+out_free_scratch:
+ __free_page(scratch);
+out:
+ dprintk("%s returns %d\n", __func__, status);
+ if (status) {
+ kfree(lseg);
+ return ERR_PTR(status);
+ }
+ return lseg;
+}
+
+static void
+bl_return_range(struct pnfs_layout_hdr *lo,
+ struct pnfs_layout_range *range)
+{
+ struct pnfs_block_layout *bl = BLK_LO2EXT(lo);
+ sector_t offset = range->offset >> SECTOR_SHIFT, end;
+
+ if (range->offset % 8) {
+ dprintk("%s: offset %lld not block size aligned\n",
+ __func__, range->offset);
+ return;
+ }
+
+ if (range->length != NFS4_MAX_UINT64) {
+ if (range->length % 8) {
+ dprintk("%s: length %lld not block size aligned\n",
+ __func__, range->length);
+ return;
+ }
+
+ end = offset + (range->length >> SECTOR_SHIFT);
+ } else {
+ end = round_down(NFS4_MAX_UINT64, PAGE_SIZE);
+ }
+
+ ext_tree_remove(bl, range->iomode & IOMODE_RW, offset, end);
+}
+
+static int
+bl_prepare_layoutcommit(struct nfs4_layoutcommit_args *arg)
+{
+ return ext_tree_prepare_commit(arg);
+}
+
+static void
+bl_cleanup_layoutcommit(struct nfs4_layoutcommit_data *lcdata)
+{
+ ext_tree_mark_committed(&lcdata->args, lcdata->res.status);
+}
+
+static int
+bl_set_layoutdriver(struct nfs_server *server, const struct nfs_fh *fh)
+{
+ dprintk("%s enter\n", __func__);
+
+ if (server->pnfs_blksize == 0) {
+ dprintk("%s Server did not return blksize\n", __func__);
+ return -EINVAL;
+ }
+ if (server->pnfs_blksize > PAGE_SIZE) {
+ printk(KERN_ERR "%s: pNFS blksize %d not supported.\n",
+ __func__, server->pnfs_blksize);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static bool
+is_aligned_req(struct nfs_pageio_descriptor *pgio,
+ struct nfs_page *req, unsigned int alignment)
+{
+ /*
+ * Always accept buffered writes, higher layers take care of the
+ * right alignment.
+ */
+ if (pgio->pg_dreq == NULL)
+ return true;
+
+ if (!IS_ALIGNED(req->wb_offset, alignment))
+ return false;
+
+ if (IS_ALIGNED(req->wb_bytes, alignment))
+ return true;
+
+ if (req_offset(req) + req->wb_bytes == i_size_read(pgio->pg_inode)) {
+ /*
+ * If the write goes up to the inode size, just write
+ * the full page. Data past the inode size is
+ * guaranteed to be zeroed by the higher level client
+ * code, and this behaviour is mandated by RFC 5663
+ * section 2.3.2.
+ */
+ return true;
+ }
+
+ return false;
+}
+
+static void
+bl_pg_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
+{
+ if (!is_aligned_req(pgio, req, SECTOR_SIZE)) {
+ nfs_pageio_reset_read_mds(pgio);
+ return;
+ }
+
+ pnfs_generic_pg_init_read(pgio, req);
+}
+
+/*
+ * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number
+ * of bytes (maximum @req->wb_bytes) that can be coalesced.
+ */
+static size_t
+bl_pg_test_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
+ struct nfs_page *req)
+{
+ if (!is_aligned_req(pgio, req, SECTOR_SIZE))
+ return 0;
+ return pnfs_generic_pg_test(pgio, prev, req);
+}
+
+/*
+ * Return the number of contiguous bytes for a given inode
+ * starting at page frame idx.
+ */
+static u64 pnfs_num_cont_bytes(struct inode *inode, pgoff_t idx)
+{
+ struct address_space *mapping = inode->i_mapping;
+ pgoff_t end;
+
+ /* Optimize common case that writes from 0 to end of file */
+ end = DIV_ROUND_UP(i_size_read(inode), PAGE_CACHE_SIZE);
+ if (end != inode->i_mapping->nrpages) {
+ rcu_read_lock();
+ end = page_cache_next_hole(mapping, idx + 1, ULONG_MAX);
+ rcu_read_unlock();
+ }
+
+ if (!end)
+ return i_size_read(inode) - (idx << PAGE_CACHE_SHIFT);
+ else
+ return (end - idx) << PAGE_CACHE_SHIFT;
+}
+
+static void
+bl_pg_init_write(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
+{
+ u64 wb_size;
+
+ if (!is_aligned_req(pgio, req, PAGE_SIZE)) {
+ nfs_pageio_reset_write_mds(pgio);
+ return;
+ }
+
+ if (pgio->pg_dreq == NULL)
+ wb_size = pnfs_num_cont_bytes(pgio->pg_inode,
+ req->wb_index);
+ else
+ wb_size = nfs_dreq_bytes_left(pgio->pg_dreq);
+
+ pnfs_generic_pg_init_write(pgio, req, wb_size);
+}
+
+/*
+ * Return 0 if @req cannot be coalesced into @pgio, otherwise return the number
+ * of bytes (maximum @req->wb_bytes) that can be coalesced.
+ */
+static size_t
+bl_pg_test_write(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
+ struct nfs_page *req)
+{
+ if (!is_aligned_req(pgio, req, PAGE_SIZE))
+ return 0;
+ return pnfs_generic_pg_test(pgio, prev, req);
+}
+
+static const struct nfs_pageio_ops bl_pg_read_ops = {
+ .pg_init = bl_pg_init_read,
+ .pg_test = bl_pg_test_read,
+ .pg_doio = pnfs_generic_pg_readpages,
+ .pg_cleanup = pnfs_generic_pg_cleanup,
+};
+
+static const struct nfs_pageio_ops bl_pg_write_ops = {
+ .pg_init = bl_pg_init_write,
+ .pg_test = bl_pg_test_write,
+ .pg_doio = pnfs_generic_pg_writepages,
+ .pg_cleanup = pnfs_generic_pg_cleanup,
+};
+
+static struct pnfs_layoutdriver_type blocklayout_type = {
+ .id = LAYOUT_BLOCK_VOLUME,
+ .name = "LAYOUT_BLOCK_VOLUME",
+ .owner = THIS_MODULE,
+ .flags = PNFS_LAYOUTRET_ON_SETATTR |
+ PNFS_READ_WHOLE_PAGE,
+ .read_pagelist = bl_read_pagelist,
+ .write_pagelist = bl_write_pagelist,
+ .alloc_layout_hdr = bl_alloc_layout_hdr,
+ .free_layout_hdr = bl_free_layout_hdr,
+ .alloc_lseg = bl_alloc_lseg,
+ .free_lseg = bl_free_lseg,
+ .return_range = bl_return_range,
+ .prepare_layoutcommit = bl_prepare_layoutcommit,
+ .cleanup_layoutcommit = bl_cleanup_layoutcommit,
+ .set_layoutdriver = bl_set_layoutdriver,
+ .alloc_deviceid_node = bl_alloc_deviceid_node,
+ .free_deviceid_node = bl_free_deviceid_node,
+ .pg_read_ops = &bl_pg_read_ops,
+ .pg_write_ops = &bl_pg_write_ops,
+ .sync = pnfs_generic_sync,
+};
+
+static int __init nfs4blocklayout_init(void)
+{
+ int ret;
+
+ dprintk("%s: NFSv4 Block Layout Driver Registering...\n", __func__);
+
+ ret = pnfs_register_layoutdriver(&blocklayout_type);
+ if (ret)
+ goto out;
+ ret = bl_init_pipefs();
+ if (ret)
+ goto out_unregister;
+ return 0;
+
+out_unregister:
+ pnfs_unregister_layoutdriver(&blocklayout_type);
+out:
+ return ret;
+}
+
+static void __exit nfs4blocklayout_exit(void)
+{
+ dprintk("%s: NFSv4 Block Layout Driver Unregistering...\n",
+ __func__);
+
+ bl_cleanup_pipefs();
+ pnfs_unregister_layoutdriver(&blocklayout_type);
+}
+
+MODULE_ALIAS("nfs-layouttype4-3");
+
+module_init(nfs4blocklayout_init);
+module_exit(nfs4blocklayout_exit);
Code Review / kvmfornfv.git / blobdiff