/*
* 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/buffer_head.h> /* various write calls */
#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 void print_page(struct page *page)
{
dprintk("PRINTPAGE page %p\n", page);
dprintk(" PagePrivate %d\n", PagePrivate(page));
dprintk(" PageUptodate %d\n", PageUptodate(page));
dprintk(" PageError %d\n", PageError(page));
dprintk(" PageDirty %d\n", PageDirty(page));
dprintk(" PageReferenced %d\n", PageReferenced(page));
dprintk(" PageLocked %d\n", PageLocked(page));
dprintk(" PageWriteback %d\n", PageWriteback(page));
dprintk(" PageMappedToDisk %d\n", PageMappedToDisk(page));
dprintk("\n");
}
/* Given the be associated with isect, determine if page data needs to be
* initialized.
*/
static int is_hole(struct pnfs_block_extent *be, sector_t isect)
{
if (be->be_state == PNFS_BLOCK_NONE_DATA)
return 1;
else if (be->be_state != PNFS_BLOCK_INVALID_DATA)
return 0;
else
return !bl_is_sector_init(be->be_inval, isect);
}
/* Given the be associated with isect, determine if page data can be
* written to disk.
*/
static int is_writable(struct pnfs_block_extent *be, sector_t isect)
{
return (be->be_state == PNFS_BLOCK_READWRITE_DATA ||
be->be_state == PNFS_BLOCK_INVALID_DATA);
}
/* 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, int num_se);
void *data;
int bse_count;
};
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);
rv->bse_count = 0;
}
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, p->bse_count);
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_size, (unsigned long long)bio->bi_sector);
submit_bio(rw, bio);
}
return NULL;
}
static struct bio *bl_alloc_init_bio(int npg, sector_t isect,
struct pnfs_block_extent *be,
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_sector = isect - be->be_f_offset + be->be_v_offset;
bio->bi_bdev = be->be_mdev;
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_extent *be,
void (*end_io)(struct bio *, int err),
struct parallel_io *par,
unsigned int offset, int len)
{
isect = isect + (offset >> SECTOR_SHIFT);
dprintk("%s: npg %d rw %d isect %llu offset %u len %d\n", __func__,
npg, rw, (unsigned long long)isect, offset, len);
retry:
if (!bio) {
bio = bl_alloc_init_bio(npg, isect, be, 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 struct bio *bl_add_page_to_bio(struct bio *bio, int npg, int rw,
sector_t isect, struct page *page,
struct pnfs_block_extent *be,
void (*end_io)(struct bio *, int err),
struct parallel_io *par)
{
return do_add_page_to_bio(bio, npg, rw, isect, page, be,
end_io, par, 0, PAGE_CACHE_SIZE);
}
/* This is basically copied from mpage_end_io_read */
static void bl_end_io_read(struct bio *bio, int err)
{
struct parallel_io *par = bio->bi_private;
const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
do {
struct page *page = bvec->bv_page;
if (--bvec >= bio->bi_io_vec)
prefetchw(&bvec->bv_page->flags);
if (uptodate)
SetPageUptodate(page);
} while (bvec >= bio->bi_io_vec);
if (!uptodate) {
struct nfs_read_data *rdata = par->data;
struct nfs_pgio_header *header = rdata->header;
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_read_data *rdata;
dprintk("%s enter\n", __func__);
task = container_of(work, struct rpc_task, u.tk_work);
rdata = container_of(task, struct nfs_read_data, task);
pnfs_ld_read_done(rdata);
}
static void
bl_end_par_io_read(void *data, int unused)
{
struct nfs_read_data *rdata = data;
rdata->task.tk_status = rdata->header->pnfs_error;
INIT_WORK(&rdata->task.u.tk_work, bl_read_cleanup);
schedule_work(&rdata->task.u.tk_work);
}
static enum pnfs_try_status
bl_read_pagelist(struct nfs_read_data *rdata)
{
struct nfs_pgio_header *header = rdata->header;
int i, hole;
struct bio *bio = NULL;
struct pnfs_block_extent *be = NULL, *cow_read = NULL;
sector_t isect, extent_length = 0;
struct parallel_io *par;
loff_t f_offset = rdata->args.offset;
size_t bytes_left = rdata->args.count;
unsigned int pg_offset, pg_len;
struct page **pages = rdata->args.pages;
int pg_index = rdata->args.pgbase >> PAGE_CACHE_SHIFT;
const bool is_dio = (header->dreq != NULL);
dprintk("%s enter nr_pages %u offset %lld count %u\n", __func__,
rdata->pages.npages, f_offset, (unsigned int)rdata->args.count);
par = alloc_parallel(rdata);
if (!par)
goto use_mds;
par->pnfs_callback = bl_end_par_io_read;
/* At this point, we can no longer jump to use_mds */
isect = (sector_t) (f_offset >> SECTOR_SHIFT);
/* Code assumes extents are page-aligned */
for (i = pg_index; i < rdata->pages.npages; i++) {
if (!extent_length) {
/* We've used up the previous extent */
bl_put_extent(be);
bl_put_extent(cow_read);
bio = bl_submit_bio(READ, bio);
/* Get the next one */
be = bl_find_get_extent(BLK_LSEG2EXT(header->lseg),
isect, &cow_read);
if (!be) {
header->pnfs_error = -EIO;
goto out;
}
extent_length = be->be_length -
(isect - be->be_f_offset);
if (cow_read) {
sector_t cow_length = cow_read->be_length -
(isect - cow_read->be_f_offset);
extent_length = min(extent_length, cow_length);
}
}
if (is_dio) {
pg_offset = f_offset & ~PAGE_CACHE_MASK;
if (pg_offset + bytes_left > PAGE_CACHE_SIZE)
pg_len = PAGE_CACHE_SIZE - pg_offset;
else
pg_len = bytes_left;
f_offset += pg_len;
bytes_left -= pg_len;
isect += (pg_offset >> SECTOR_SHIFT);
} else {
pg_offset = 0;
pg_len = PAGE_CACHE_SIZE;
}
hole = is_hole(be, isect);
if (hole && !cow_read) {
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);
print_page(pages[i]);
SetPageUptodate(pages[i]);
} else {
struct pnfs_block_extent *be_read;
be_read = (hole && cow_read) ? cow_read : be;
bio = do_add_page_to_bio(bio, rdata->pages.npages - i,
READ,
isect, pages[i], be_read,
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 -= PAGE_CACHE_SECTORS;
}
if ((isect << SECTOR_SHIFT) >= header->inode->i_size) {
rdata->res.eof = 1;
rdata->res.count = header->inode->i_size - rdata->args.offset;
} else {
rdata->res.count = (isect << SECTOR_SHIFT) - rdata->args.offset;
}
out:
bl_put_extent(be);
bl_put_extent(cow_read);
bl_submit_bio(READ, bio);
put_parallel(par);
return PNFS_ATTEMPTED;
use_mds:
dprintk("Giving up and using normal NFS\n");
return PNFS_NOT_ATTEMPTED;
}
static void mark_extents_written(struct pnfs_block_layout *bl,
__u64 offset, __u32 count)
{
sector_t isect, end;
struct pnfs_block_extent *be;
struct pnfs_block_short_extent *se;
dprintk("%s(%llu, %u)\n", __func__, offset, count);
if (count == 0)
return;
isect = (offset & (long)(PAGE_CACHE_MASK)) >> SECTOR_SHIFT;
end = (offset + count + PAGE_CACHE_SIZE - 1) & (long)(PAGE_CACHE_MASK);
end >>= SECTOR_SHIFT;
while (isect < end) {
sector_t len;
be = bl_find_get_extent(bl, isect, NULL);
BUG_ON(!be); /* FIXME */
len = min(end, be->be_f_offset + be->be_length) - isect;
if (be->be_state == PNFS_BLOCK_INVALID_DATA) {
se = bl_pop_one_short_extent(be->be_inval);
BUG_ON(!se);
bl_mark_for_commit(be, isect, len, se);
}
isect += len;
bl_put_extent(be);
}
}
static void bl_end_io_write_zero(struct bio *bio, int err)
{
struct parallel_io *par = bio->bi_private;
const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
do {
struct page *page = bvec->bv_page;
if (--bvec >= bio->bi_io_vec)
prefetchw(&bvec->bv_page->flags);
/* This is the zeroing page we added */
end_page_writeback(page);
page_cache_release(page);
} while (bvec >= bio->bi_io_vec);
if (unlikely(!uptodate)) {
struct nfs_write_data *data = par->data;
struct nfs_pgio_header *header = data->header;
if (!header->pnfs_error)
header->pnfs_error = -EIO;
pnfs_set_lo_fail(header->lseg);
}
bio_put(bio);
put_parallel(par);
}
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_write_data *data = par->data;
struct nfs_pgio_header *header = data->header;
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;
struct nfs_write_data *wdata;
dprintk("%s enter\n", __func__);
task = container_of(work, struct rpc_task, u.tk_work);
wdata = container_of(task, struct nfs_write_data, task);
if (likely(!wdata->header->pnfs_error)) {
/* Marks for LAYOUTCOMMIT */
mark_extents_written(BLK_LSEG2EXT(wdata->header->lseg),
wdata->args.offset, wdata->args.count);
}
pnfs_ld_write_done(wdata);
}
/* Called when last of bios associated with a bl_write_pagelist call finishes */
static void bl_end_par_io_write(void *data, int num_se)
{
struct nfs_write_data *wdata = data;
if (unlikely(wdata->header->pnfs_error)) {
bl_free_short_extents(&BLK_LSEG2EXT(wdata->header->lseg)->bl_inval,
num_se);
}
wdata->task.tk_status = wdata->header->pnfs_error;
wdata->verf.committed = NFS_FILE_SYNC;
INIT_WORK(&wdata->task.u.tk_work, bl_write_cleanup);
schedule_work(&wdata->task.u.tk_work);
}
/* FIXME STUB - mark intersection of layout and page as bad, so is not
* used again.
*/
static void mark_bad_read(void)
{
return;
}
/*
* map_block: map a requested I/0 block (isect) into an offset in the LVM
* block_device
*/
static void
map_block(struct buffer_head *bh, sector_t isect, struct pnfs_block_extent *be)
{
dprintk("%s enter be=%p\n", __func__, be);
set_buffer_mapped(bh);
bh->b_bdev = be->be_mdev;
bh->b_blocknr = (isect - be->be_f_offset + be->be_v_offset) >>
(be->be_mdev->bd_inode->i_blkbits - SECTOR_SHIFT);
dprintk("%s isect %llu, bh->b_blocknr %ld, using bsize %Zd\n",
__func__, (unsigned long long)isect, (long)bh->b_blocknr,
bh->b_size);
return;
}
static void
bl_read_single_end_io(struct bio *bio, int error)
{
struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
struct page *page = bvec->bv_page;
/* Only one page in bvec */
unlock_page(page);
}
static int
bl_do_readpage_sync(struct page *page, struct pnfs_block_extent *be,
unsigned int offset, unsigned int len)
{
struct bio *bio;
struct page *shadow_page;
sector_t isect;
char *kaddr, *kshadow_addr;
int ret = 0;
dprintk("%s: offset %u len %u\n", __func__, offset, len);
shadow_page = alloc_page(GFP_NOFS | __GFP_HIGHMEM);
if (shadow_page == NULL)
return -ENOMEM;
bio = bio_alloc(GFP_NOIO, 1);
if (bio == NULL)
return -ENOMEM;
isect = (page->index << PAGE_CACHE_SECTOR_SHIFT) +
(offset / SECTOR_SIZE);
bio->bi_sector = isect - be->be_f_offset + be->be_v_offset;
bio->bi_bdev = be->be_mdev;
bio->bi_end_io = bl_read_single_end_io;
lock_page(shadow_page);
if (bio_add_page(bio, shadow_page,
SECTOR_SIZE, round_down(offset, SECTOR_SIZE)) == 0) {
unlock_page(shadow_page);
bio_put(bio);
return -EIO;
}
submit_bio(READ, bio);
wait_on_page_locked(shadow_page);
if (unlikely(!test_bit(BIO_UPTODATE, &bio->bi_flags))) {
ret = -EIO;
} else {
kaddr = kmap_atomic(page);
kshadow_addr = kmap_atomic(shadow_page);
memcpy(kaddr + offset, kshadow_addr + offset, len);
kunmap_atomic(kshadow_addr);
kunmap_atomic(kaddr);
}
__free_page(shadow_page);
bio_put(bio);
return ret;
}
static int
bl_read_partial_page_sync(struct page *page, struct pnfs_block_extent *be,
unsigned int dirty_offset, unsigned int dirty_len,
bool full_page)
{
int ret = 0;
unsigned int start, end;
if (full_page) {
start = 0;
end = PAGE_CACHE_SIZE;
} else {
start = round_down(dirty_offset, SECTOR_SIZE);
end = round_up(dirty_offset + dirty_len, SECTOR_SIZE);
}
dprintk("%s: offset %u len %d\n", __func__, dirty_offset, dirty_len);
if (!be) {
zero_user_segments(page, start, dirty_offset,
dirty_offset + dirty_len, end);
if (start == 0 && end == PAGE_CACHE_SIZE &&
trylock_page(page)) {
SetPageUptodate(page);
unlock_page(page);
}
return ret;
}
if (start != dirty_offset)
ret = bl_do_readpage_sync(page, be, start, dirty_offset - start);
if (!ret && (dirty_offset + dirty_len < end))
ret = bl_do_readpage_sync(page, be, dirty_offset + dirty_len,
end - dirty_offset - dirty_len);
return ret;
}
/* Given an unmapped page, zero it or read in page for COW, page is locked
* by caller.
*/
static int
init_page_for_write(struct page *page, struct pnfs_block_extent *cow_read)
{
struct buffer_head *bh = NULL;
int ret = 0;
sector_t isect;
dprintk("%s enter, %p\n", __func__, page);
BUG_ON(PageUptodate(page));
if (!cow_read) {
zero_user_segment(page, 0, PAGE_SIZE);
SetPageUptodate(page);
goto cleanup;
}
bh = alloc_page_buffers(page, PAGE_CACHE_SIZE, 0);
if (!bh) {
ret = -ENOMEM;
goto cleanup;
}
isect = (sector_t) page->index << PAGE_CACHE_SECTOR_SHIFT;
map_block(bh, isect, cow_read);
if (!bh_uptodate_or_lock(bh))
ret = bh_submit_read(bh);
if (ret)
goto cleanup;
SetPageUptodate(page);
cleanup:
if (bh)
free_buffer_head(bh);
if (ret) {
/* Need to mark layout with bad read...should now
* just use nfs4 for reads and writes.
*/
mark_bad_read();
}
return ret;
}
/* Find or create a zeroing page marked being writeback.
* Return ERR_PTR on error, NULL to indicate skip this page and page itself
* to indicate write out.
*/
static struct page *
bl_find_get_zeroing_page(struct inode *inode, pgoff_t index,
struct pnfs_block_extent *cow_read)
{
struct page *page;
int locked = 0;
page = find_get_page(inode->i_mapping, index);
if (page)
goto check_page;
page = find_or_create_page(inode->i_mapping, index, GFP_NOFS);
if (unlikely(!page)) {
dprintk("%s oom\n", __func__);
return ERR_PTR(-ENOMEM);
}
locked = 1;
check_page:
/* PageDirty: Other will write this out
* PageWriteback: Other is writing this out
* PageUptodate: It was read before
*/
if (PageDirty(page) || PageWriteback(page)) {
print_page(page);
if (locked)
unlock_page(page);
page_cache_release(page);
return NULL;
}
if (!locked) {
lock_page(page);
locked = 1;
goto check_page;
}
if (!PageUptodate(page)) {
/* New page, readin or zero it */
init_page_for_write(page, cow_read);
}
set_page_writeback(page);
unlock_page(page);
return page;
}
static enum pnfs_try_status
bl_write_pagelist(struct nfs_write_data *wdata, int sync)
{
struct nfs_pgio_header *header = wdata->header;
int i, ret, npg_zero, pg_index, last = 0;
struct bio *bio = NULL;
struct pnfs_block_extent *be = NULL, *cow_read = NULL;
sector_t isect, last_isect = 0, extent_length = 0;
struct parallel_io *par = NULL;
loff_t offset = wdata->args.offset;
size_t count = wdata->args.count;
unsigned int pg_offset, pg_len, saved_len;
struct page **pages = wdata->args.pages;
struct page *page;
pgoff_t index;
u64 temp;
int npg_per_block =
NFS_SERVER(header->inode)->pnfs_blksize >> PAGE_CACHE_SHIFT;
dprintk("%s enter, %Zu@%lld\n", __func__, count, offset);
if (header->dreq != NULL &&
(!IS_ALIGNED(offset, NFS_SERVER(header->inode)->pnfs_blksize) ||
!IS_ALIGNED(count, NFS_SERVER(header->inode)->pnfs_blksize))) {
dprintk("pnfsblock nonblock aligned DIO writes. Resend MDS\n");
goto out_mds;
}
/* At this point, wdata->pages 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(wdata);
if (!par)
goto out_mds;
par->pnfs_callback = bl_end_par_io_write;
/* At this point, have to be more careful with error handling */
isect = (sector_t) ((offset & (long)PAGE_CACHE_MASK) >> SECTOR_SHIFT);
be = bl_find_get_extent(BLK_LSEG2EXT(header->lseg), isect, &cow_read);
if (!be || !is_writable(be, isect)) {
dprintk("%s no matching extents!\n", __func__);
goto out_mds;
}
/* First page inside INVALID extent */
if (be->be_state == PNFS_BLOCK_INVALID_DATA) {
if (likely(!bl_push_one_short_extent(be->be_inval)))
par->bse_count++;
else
goto out_mds;
temp = offset >> PAGE_CACHE_SHIFT;
npg_zero = do_div(temp, npg_per_block);
isect = (sector_t) (((offset - npg_zero * PAGE_CACHE_SIZE) &
(long)PAGE_CACHE_MASK) >> SECTOR_SHIFT);
extent_length = be->be_length - (isect - be->be_f_offset);
fill_invalid_ext:
dprintk("%s need to zero %d pages\n", __func__, npg_zero);
for (;npg_zero > 0; npg_zero--) {
if (bl_is_sector_init(be->be_inval, isect)) {
dprintk("isect %llu already init\n",
(unsigned long long)isect);
goto next_page;
}
/* page ref released in bl_end_io_write_zero */
index = isect >> PAGE_CACHE_SECTOR_SHIFT;
dprintk("%s zero %dth page: index %lu isect %llu\n",
__func__, npg_zero, index,
(unsigned long long)isect);
page = bl_find_get_zeroing_page(header->inode, index,
cow_read);
if (unlikely(IS_ERR(page))) {
header->pnfs_error = PTR_ERR(page);
goto out;
} else if (page == NULL)
goto next_page;
ret = bl_mark_sectors_init(be->be_inval, isect,
PAGE_CACHE_SECTORS);
if (unlikely(ret)) {
dprintk("%s bl_mark_sectors_init fail %d\n",
__func__, ret);
end_page_writeback(page);
page_cache_release(page);
header->pnfs_error = ret;
goto out;
}
if (likely(!bl_push_one_short_extent(be->be_inval)))
par->bse_count++;
else {
end_page_writeback(page);
page_cache_release(page);
header->pnfs_error = -ENOMEM;
goto out;
}
/* FIXME: This should be done in bi_end_io */
mark_extents_written(BLK_LSEG2EXT(header->lseg),
page->index << PAGE_CACHE_SHIFT,
PAGE_CACHE_SIZE);
bio = bl_add_page_to_bio(bio, npg_zero, WRITE,
isect, page, be,
bl_end_io_write_zero, par);
if (IS_ERR(bio)) {
header->pnfs_error = PTR_ERR(bio);
bio = NULL;
goto out;
}
next_page:
isect += PAGE_CACHE_SECTORS;
extent_length -= PAGE_CACHE_SECTORS;
}
if (last)
goto write_done;
}
bio = bl_submit_bio(WRITE, bio);
/* Middle pages */
pg_index = wdata->args.pgbase >> PAGE_CACHE_SHIFT;
for (i = pg_index; i < wdata->pages.npages; i++) {
if (!extent_length) {
/* We've used up the previous extent */
bl_put_extent(be);
bl_put_extent(cow_read);
bio = bl_submit_bio(WRITE, bio);
/* Get the next one */
be = bl_find_get_extent(BLK_LSEG2EXT(header->lseg),
isect, &cow_read);
if (!be || !is_writable(be, isect)) {
header->pnfs_error = -EINVAL;
goto out;
}
if (be->be_state == PNFS_BLOCK_INVALID_DATA) {
if (likely(!bl_push_one_short_extent(
be->be_inval)))
par->bse_count++;
else {
header->pnfs_error = -ENOMEM;
goto out;
}
}
extent_length = be->be_length -
(isect - be->be_f_offset);
}
dprintk("%s offset %lld count %Zu\n", __func__, offset, count);
pg_offset = offset & ~PAGE_CACHE_MASK;
if (pg_offset + count > PAGE_CACHE_SIZE)
pg_len = PAGE_CACHE_SIZE - pg_offset;
else
pg_len = count;
saved_len = pg_len;
if (be->be_state == PNFS_BLOCK_INVALID_DATA &&
!bl_is_sector_init(be->be_inval, isect)) {
ret = bl_read_partial_page_sync(pages[i], cow_read,
pg_offset, pg_len, true);
if (ret) {
dprintk("%s bl_read_partial_page_sync fail %d\n",
__func__, ret);
header->pnfs_error = ret;
goto out;
}
ret = bl_mark_sectors_init(be->be_inval, isect,
PAGE_CACHE_SECTORS);
if (unlikely(ret)) {
dprintk("%s bl_mark_sectors_init fail %d\n",
__func__, ret);
header->pnfs_error = ret;
goto out;
}
/* Expand to full page write */
pg_offset = 0;
pg_len = PAGE_CACHE_SIZE;
} else if ((pg_offset & (SECTOR_SIZE - 1)) ||
(pg_len & (SECTOR_SIZE - 1))){
/* ahh, nasty case. We have to do sync full sector
* read-modify-write cycles.
*/
unsigned int saved_offset = pg_offset;
ret = bl_read_partial_page_sync(pages[i], be, pg_offset,
pg_len, false);
pg_offset = round_down(pg_offset, SECTOR_SIZE);
pg_len = round_up(saved_offset + pg_len, SECTOR_SIZE)
- pg_offset;
}
bio = do_add_page_to_bio(bio, wdata->pages.npages - i, WRITE,
isect, pages[i], be,
bl_end_io_write, par,
pg_offset, pg_len);
if (IS_ERR(bio)) {
header->pnfs_error = PTR_ERR(bio);
bio = NULL;
goto out;
}
offset += saved_len;
count -= saved_len;
isect += PAGE_CACHE_SECTORS;
last_isect = isect;
extent_length -= PAGE_CACHE_SECTORS;
}
/* Last page inside INVALID extent */
if (be->be_state == PNFS_BLOCK_INVALID_DATA) {
bio = bl_submit_bio(WRITE, bio);
temp = last_isect >> PAGE_CACHE_SECTOR_SHIFT;
npg_zero = npg_per_block - do_div(temp, npg_per_block);
if (npg_zero < npg_per_block) {
last = 1;
goto fill_invalid_ext;
}
}
write_done:
wdata->res.count = wdata->args.count;
out:
bl_put_extent(be);
bl_put_extent(cow_read);
bl_submit_bio(WRITE, bio);
put_parallel(par);
return PNFS_ATTEMPTED;
out_mds:
bl_put_extent(be);
bl_put_extent(cow_read);
kfree(par);
return PNFS_NOT_ATTEMPTED;
}
/* FIXME - range ignored */
static void
release_extents(struct pnfs_block_layout *bl, struct pnfs_layout_range *range)
{
int i;
struct pnfs_block_extent *be;
spin_lock(&bl->bl_ext_lock);
for (i = 0; i < EXTENT_LISTS; i++) {
while (!list_empty(&bl->bl_extents[i])) {
be = list_first_entry(&bl->bl_extents[i],
struct pnfs_block_extent,
be_node);
list_del(&be->be_node);
bl_put_extent(be);
}
}
spin_unlock(&bl->bl_ext_lock);
}
static void
release_inval_marks(struct pnfs_inval_markings *marks)
{
struct pnfs_inval_tracking *pos, *temp;
struct pnfs_block_short_extent *se, *stemp;
list_for_each_entry_safe(pos, temp, &marks->im_tree.mtt_stub, it_link) {
list_del(&pos->it_link);
kfree(pos);
}
list_for_each_entry_safe(se, stemp, &marks->im_extents, bse_node) {
list_del(&se->bse_node);
kfree(se);
}
return;
}
static void bl_free_layout_hdr(struct pnfs_layout_hdr *lo)
{
struct pnfs_block_layout *bl = BLK_LO2EXT(lo);
dprintk("%s enter\n", __func__);
release_extents(bl, NULL);
release_inval_marks(&bl->bl_inval);
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;
spin_lock_init(&bl->bl_ext_lock);
INIT_LIST_HEAD(&bl->bl_extents[0]);
INIT_LIST_HEAD(&bl->bl_extents[1]);
INIT_LIST_HEAD(&bl->bl_commit);
INIT_LIST_HEAD(&bl->bl_committing);
bl->bl_count = 0;
bl->bl_blocksize = NFS_SERVER(inode)->pnfs_blksize >> SECTOR_SHIFT;
BL_INIT_INVAL_MARKS(&bl->bl_inval, bl->bl_blocksize);
return &bl->bl_layout;
}
static void bl_free_lseg(struct pnfs_layout_segment *lseg)
{
dprintk("%s enter\n", __func__);
kfree(lseg);
}
/* We pretty much ignore lseg, and store all data layout wide, so we
* can correctly merge.
*/
static struct pnfs_layout_segment *bl_alloc_lseg(struct pnfs_layout_hdr *lo,
struct nfs4_layoutget_res *lgr,
gfp_t gfp_flags)
{
struct pnfs_layout_segment *lseg;
int status;
dprintk("%s enter\n", __func__);
lseg = kzalloc(sizeof(*lseg), gfp_flags);
if (!lseg)
return ERR_PTR(-ENOMEM);
status = nfs4_blk_process_layoutget(lo, lgr, gfp_flags);
if (status) {
/* We don't want to call the full-blown bl_free_lseg,
* since on error extents were not touched.
*/
kfree(lseg);
return ERR_PTR(status);
}
return lseg;
}
static void
bl_encode_layoutcommit(struct pnfs_layout_hdr *lo, struct xdr_stream *xdr,
const struct nfs4_layoutcommit_args *arg)
{
dprintk("%s enter\n", __func__);
encode_pnfs_block_layoutupdate(BLK_LO2EXT(lo), xdr, arg);
}
static void
bl_cleanup_layoutcommit(struct nfs4_layoutcommit_data *lcdata)
{
struct pnfs_layout_hdr *lo = NFS_I(lcdata->args.inode)->layout;
dprintk("%s enter\n", __func__);
clean_pnfs_block_layoutupdate(BLK_LO2EXT(lo), &lcdata->args, lcdata->res.status);
}
static void free_blk_mountid(struct block_mount_id *mid)
{
if (mid) {
struct pnfs_block_dev *dev, *tmp;
/* No need to take bm_lock as we are last user freeing bm_devlist */
list_for_each_entry_safe(dev, tmp, &mid->bm_devlist, bm_node) {
list_del(&dev->bm_node);
bl_free_block_dev(dev);
}
kfree(mid);
}
}
/* This is mostly copied from the filelayout_get_device_info function.
* It seems much of this should be at the generic pnfs level.
*/
static struct pnfs_block_dev *
nfs4_blk_get_deviceinfo(struct nfs_server *server, const struct nfs_fh *fh,
struct nfs4_deviceid *d_id)
{
struct pnfs_device *dev;
struct pnfs_block_dev *rv;
u32 max_resp_sz;
int max_pages;
struct page **pages = NULL;
int i, rc;
/*
* Use the session max response size as the basis for setting
* GETDEVICEINFO's maxcount
*/
max_resp_sz = server->nfs_client->cl_session->fc_attrs.max_resp_sz;
max_pages = nfs_page_array_len(0, max_resp_sz);
dprintk("%s max_resp_sz %u max_pages %d\n",
__func__, max_resp_sz, max_pages);
dev = kmalloc(sizeof(*dev), GFP_NOFS);
if (!dev) {
dprintk("%s kmalloc failed\n", __func__);
return ERR_PTR(-ENOMEM);
}
pages = kzalloc(max_pages * sizeof(struct page *), GFP_NOFS);
if (pages == NULL) {
kfree(dev);
return ERR_PTR(-ENOMEM);
}
for (i = 0; i < max_pages; i++) {
pages[i] = alloc_page(GFP_NOFS);
if (!pages[i]) {
rv = ERR_PTR(-ENOMEM);
goto out_free;
}
}
memcpy(&dev->dev_id, d_id, sizeof(*d_id));
dev->layout_type = LAYOUT_BLOCK_VOLUME;
dev->pages = pages;
dev->pgbase = 0;
dev->pglen = PAGE_SIZE * max_pages;
dev->mincount = 0;
dprintk("%s: dev_id: %s\n", __func__, dev->dev_id.data);
rc = nfs4_proc_getdeviceinfo(server, dev);
dprintk("%s getdevice info returns %d\n", __func__, rc);
if (rc) {
rv = ERR_PTR(rc);
goto out_free;
}
rv = nfs4_blk_decode_device(server, dev);
out_free:
for (i = 0; i < max_pages; i++)
__free_page(pages[i]);
kfree(pages);
kfree(dev);
return rv;
}
static int
bl_set_layoutdriver(struct nfs_server *server, const struct nfs_fh *fh)
{
struct block_mount_id *b_mt_id = NULL;
struct pnfs_devicelist *dlist = NULL;
struct pnfs_block_dev *bdev;
LIST_HEAD(block_disklist);
int status, i;
dprintk("%s enter\n", __func__);
if (server->pnfs_blksize == 0) {
dprintk("%s Server did not return blksize\n", __func__);
return -EINVAL;
}
b_mt_id = kzalloc(sizeof(struct block_mount_id), GFP_NOFS);
if (!b_mt_id) {
status = -ENOMEM;
goto out_error;
}
/* Initialize nfs4 block layout mount id */
spin_lock_init(&b_mt_id->bm_lock);
INIT_LIST_HEAD(&b_mt_id->bm_devlist);
dlist = kmalloc(sizeof(struct pnfs_devicelist), GFP_NOFS);
if (!dlist) {
status = -ENOMEM;
goto out_error;
}
dlist->eof = 0;
while (!dlist->eof) {
status = nfs4_proc_getdevicelist(server, fh, dlist);
if (status)
goto out_error;
dprintk("%s GETDEVICELIST numdevs=%i, eof=%i\n",
__func__, dlist->num_devs, dlist->eof);
for (i = 0; i < dlist->num_devs; i++) {
bdev = nfs4_blk_get_deviceinfo(server, fh,
&dlist->dev_id[i]);
if (IS_ERR(bdev)) {
status = PTR_ERR(bdev);
goto out_error;
}
spin_lock(&b_mt_id->bm_lock);
list_add(&bdev->bm_node, &b_mt_id->bm_devlist);
spin_unlock(&b_mt_id->bm_lock);
}
}
dprintk("%s SUCCESS\n", __func__);
server->pnfs_ld_data = b_mt_id;
out_return:
kfree(dlist);
return status;
out_error:
free_blk_mountid(b_mt_id);
goto out_return;
}
static int
bl_clear_layoutdriver(struct nfs_server *server)
{
struct block_mount_id *b_mt_id = server->pnfs_ld_data;
dprintk("%s enter\n", __func__);
free_blk_mountid(b_mt_id);
dprintk("%s RETURNS\n", __func__);
return 0;
}
static bool
is_aligned_req(struct nfs_page *req, unsigned int alignment)
{
return IS_ALIGNED(req->wb_offset, alignment) &&
IS_ALIGNED(req->wb_bytes, alignment);
}
static void
bl_pg_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
{
if (pgio->pg_dreq != NULL &&
!is_aligned_req(req, SECTOR_SIZE))
nfs_pageio_reset_read_mds(pgio);
else
pnfs_generic_pg_init_read(pgio, req);
}
static bool
bl_pg_test_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
struct nfs_page *req)
{
if (pgio->pg_dreq != NULL &&
!is_aligned_req(req, SECTOR_SIZE))
return false;
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 != NFS_I(inode)->npages) {
rcu_read_lock();
end = radix_tree_next_hole(&mapping->page_tree, 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)
{
if (pgio->pg_dreq != NULL &&
!is_aligned_req(req, PAGE_CACHE_SIZE)) {
nfs_pageio_reset_write_mds(pgio);
} else {
u64 wb_size;
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);
}
}
static bool
bl_pg_test_write(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
struct nfs_page *req)
{
if (pgio->pg_dreq != NULL &&
!is_aligned_req(req, PAGE_CACHE_SIZE))
return false;
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,
};
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,
};
static struct pnfs_layoutdriver_type blocklayout_type = {
.id = LAYOUT_BLOCK_VOLUME,
.name = "LAYOUT_BLOCK_VOLUME",
.owner = THIS_MODULE,
.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,
.encode_layoutcommit = bl_encode_layoutcommit,
.cleanup_layoutcommit = bl_cleanup_layoutcommit,
.set_layoutdriver = bl_set_layoutdriver,
.clear_layoutdriver = bl_clear_layoutdriver,
.pg_read_ops = &bl_pg_read_ops,
.pg_write_ops = &bl_pg_write_ops,
};
static const struct rpc_pipe_ops bl_upcall_ops = {
.upcall = rpc_pipe_generic_upcall,
.downcall = bl_pipe_downcall,
.destroy_msg = bl_pipe_destroy_msg,
};
static struct dentry *nfs4blocklayout_register_sb(struct super_block *sb,
struct rpc_pipe *pipe)
{
struct dentry *dir, *dentry;
dir = rpc_d_lookup_sb(sb, NFS_PIPE_DIRNAME);
if (dir == NULL)
return ERR_PTR(-ENOENT);
dentry = rpc_mkpipe_dentry(dir, "blocklayout", NULL, pipe);
dput(dir);
return dentry;
}
static void nfs4blocklayout_unregister_sb(struct super_block *sb,
struct rpc_pipe *pipe)
{
if (pipe->dentry)
rpc_unlink(pipe->dentry);
}
static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event,
void *ptr)
{
struct super_block *sb = ptr;
struct net *net = sb->s_fs_info;
struct nfs_net *nn = net_generic(net, nfs_net_id);
struct dentry *dentry;
int ret = 0;
if (!try_module_get(THIS_MODULE))
return 0;
if (nn->bl_device_pipe == NULL) {
module_put(THIS_MODULE);
return 0;
}
switch (event) {
case RPC_PIPEFS_MOUNT:
dentry = nfs4blocklayout_register_sb(sb, nn->bl_device_pipe);
if (IS_ERR(dentry)) {
ret = PTR_ERR(dentry);
break;
}
nn->bl_device_pipe->dentry = dentry;
break;
case RPC_PIPEFS_UMOUNT:
if (nn->bl_device_pipe->dentry)
nfs4blocklayout_unregister_sb(sb, nn->bl_device_pipe);
break;
default:
ret = -ENOTSUPP;
break;
}
module_put(THIS_MODULE);
return ret;
}
static struct notifier_block nfs4blocklayout_block = {
.notifier_call = rpc_pipefs_event,
};
static struct dentry *nfs4blocklayout_register_net(struct net *net,
struct rpc_pipe *pipe)
{
struct super_block *pipefs_sb;
struct dentry *dentry;
pipefs_sb = rpc_get_sb_net(net);
if (!pipefs_sb)
return NULL;
dentry = nfs4blocklayout_register_sb(pipefs_sb, pipe);
rpc_put_sb_net(net);
return dentry;
}
static void nfs4blocklayout_unregister_net(struct net *net,
struct rpc_pipe *pipe)
{
struct super_block *pipefs_sb;
pipefs_sb = rpc_get_sb_net(net);
if (pipefs_sb) {
nfs4blocklayout_unregister_sb(pipefs_sb, pipe);
rpc_put_sb_net(net);
}
}
static int nfs4blocklayout_net_init(struct net *net)
{
struct nfs_net *nn = net_generic(net, nfs_net_id);
struct dentry *dentry;
init_waitqueue_head(&nn->bl_wq);
nn->bl_device_pipe = rpc_mkpipe_data(&bl_upcall_ops, 0);
if (IS_ERR(nn->bl_device_pipe))
return PTR_ERR(nn->bl_device_pipe);
dentry = nfs4blocklayout_register_net(net, nn->bl_device_pipe);
if (IS_ERR(dentry)) {
rpc_destroy_pipe_data(nn->bl_device_pipe);
return PTR_ERR(dentry);
}
nn->bl_device_pipe->dentry = dentry;
return 0;
}
static void nfs4blocklayout_net_exit(struct net *net)
{
struct nfs_net *nn = net_generic(net, nfs_net_id);
nfs4blocklayout_unregister_net(net, nn->bl_device_pipe);
rpc_destroy_pipe_data(nn->bl_device_pipe);
nn->bl_device_pipe = NULL;
}
static struct pernet_operations nfs4blocklayout_net_ops = {
.init = nfs4blocklayout_net_init,
.exit = nfs4blocklayout_net_exit,
};
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 = rpc_pipefs_notifier_register(&nfs4blocklayout_block);
if (ret)
goto out_remove;
ret = register_pernet_subsys(&nfs4blocklayout_net_ops);
if (ret)
goto out_notifier;
out:
return ret;
out_notifier:
rpc_pipefs_notifier_unregister(&nfs4blocklayout_block);
out_remove:
pnfs_unregister_layoutdriver(&blocklayout_type);
return ret;
}
static void __exit nfs4blocklayout_exit(void)
{
dprintk("%s: NFSv4 Block Layout Driver Unregistering...\n",
__func__);
rpc_pipefs_notifier_unregister(&nfs4blocklayout_block);
unregister_pernet_subsys(&nfs4blocklayout_net_ops);
pnfs_unregister_layoutdriver(&blocklayout_type);
}
MODULE_ALIAS("nfs-layouttype4-3");
module_init(nfs4blocklayout_init);
module_exit(nfs4blocklayout_exit);