[mirror_ubuntu-bionic-kernel.git] / fs / gfs2 / ops_vm.c

/*
 * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
 * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
 *
 * This copyrighted material is made available to anyone wishing to use,
 * modify, copy, or redistribute it subject to the terms and conditions
 * of the GNU General Public License v.2.
 */

#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/completion.h>
#include <linux/buffer_head.h>
#include <linux/mm.h>
#include <linux/pagemap.h>
#include <linux/gfs2_ondisk.h>

#include "gfs2.h"
#include "lm_interface.h"
#include "incore.h"
#include "bmap.h"
#include "glock.h"
#include "inode.h"
#include "ops_vm.h"
#include "quota.h"
#include "rgrp.h"
#include "trans.h"
#include "util.h"

static void pfault_be_greedy(struct gfs2_inode *ip)
{
	unsigned int time;

	spin_lock(&ip->i_spin);
	time = ip->i_greedy;
	ip->i_last_pfault = jiffies;
	spin_unlock(&ip->i_spin);

	igrab(&ip->i_inode);
	if (gfs2_glock_be_greedy(ip->i_gl, time))
		iput(&ip->i_inode);
}

static struct page *gfs2_private_nopage(struct vm_area_struct *area,
					unsigned long address, int *type)
{
	struct gfs2_inode *ip = GFS2_I(area->vm_file->f_mapping->host);
	struct page *result;

	set_bit(GIF_PAGED, &ip->i_flags);

	result = filemap_nopage(area, address, type);

	if (result && result != NOPAGE_OOM)
		pfault_be_greedy(ip);

	return result;
}

static int alloc_page_backing(struct gfs2_inode *ip, struct page *page)
{
	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
	unsigned long index = page->index;
	uint64_t lblock = index << (PAGE_CACHE_SHIFT -
				    sdp->sd_sb.sb_bsize_shift);
	unsigned int blocks = PAGE_CACHE_SIZE >> sdp->sd_sb.sb_bsize_shift;
	struct gfs2_alloc *al;
	unsigned int data_blocks, ind_blocks;
	unsigned int x;
	int error;

	al = gfs2_alloc_get(ip);

	error = gfs2_quota_lock(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
	if (error)
		goto out;

	error = gfs2_quota_check(ip, ip->i_di.di_uid, ip->i_di.di_gid);
	if (error)
		goto out_gunlock_q;

	gfs2_write_calc_reserv(ip, PAGE_CACHE_SIZE, &data_blocks, &ind_blocks);

	al->al_requested = data_blocks + ind_blocks;

	error = gfs2_inplace_reserve(ip);
	if (error)
		goto out_gunlock_q;

	error = gfs2_trans_begin(sdp, al->al_rgd->rd_ri.ri_length +
				 ind_blocks + RES_DINODE +
				 RES_STATFS + RES_QUOTA, 0);
	if (error)
		goto out_ipres;

	if (gfs2_is_stuffed(ip)) {
		error = gfs2_unstuff_dinode(ip, NULL);
		if (error)
			goto out_trans;
	}

	for (x = 0; x < blocks; ) {
		uint64_t dblock;
		unsigned int extlen;
		int new = 1;

		error = gfs2_extent_map(&ip->i_inode, lblock, &new, &dblock, &extlen);
		if (error)
			goto out_trans;

		lblock += extlen;
		x += extlen;
	}

	gfs2_assert_warn(sdp, al->al_alloced);

 out_trans:
	gfs2_trans_end(sdp);

 out_ipres:
	gfs2_inplace_release(ip);

 out_gunlock_q:
	gfs2_quota_unlock(ip);

 out:
	gfs2_alloc_put(ip);

	return error;
}

static struct page *gfs2_sharewrite_nopage(struct vm_area_struct *area,
					   unsigned long address, int *type)
{
	struct file *file = area->vm_file;
	struct gfs2_file *gf = file->private_data;
	struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
	struct gfs2_holder i_gh;
	struct page *result = NULL;
	unsigned long index = ((address - area->vm_start) >> PAGE_CACHE_SHIFT) +
			      area->vm_pgoff;
	int alloc_required;
	int error;

	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
	if (error)
		return NULL;

	set_bit(GIF_PAGED, &ip->i_flags);
	set_bit(GIF_SW_PAGED, &ip->i_flags);

	error = gfs2_write_alloc_required(ip, (u64)index << PAGE_CACHE_SHIFT,
					  PAGE_CACHE_SIZE, &alloc_required);
	if (error)
		goto out;

	set_bit(GFF_EXLOCK, &gf->f_flags);
	result = filemap_nopage(area, address, type);
	clear_bit(GFF_EXLOCK, &gf->f_flags);
	if (!result || result == NOPAGE_OOM)
		goto out;

	if (alloc_required) {
		error = alloc_page_backing(ip, result);
		if (error) {
			page_cache_release(result);
			result = NULL;
			goto out;
		}
		set_page_dirty(result);
	}

	pfault_be_greedy(ip);
out:
	gfs2_glock_dq_uninit(&i_gh);

	return result;
}

struct vm_operations_struct gfs2_vm_ops_private = {
	.nopage = gfs2_private_nopage,
};

struct vm_operations_struct gfs2_vm_ops_sharewrite = {
	.nopage = gfs2_sharewrite_nopage,
};
Commit	Line	Data
b3b94faa DT	1	/*
b3b94faa DT	2	* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
3a8a9a10	3	* Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
b3b94faa DT	4	*
	5	* This copyrighted material is made available to anyone wishing to use,
	6	* modify, copy, or redistribute it subject to the terms and conditions
	7	* of the GNU General Public License v.2.
	8	*/
	9
	10	#include <linux/sched.h>
	11	#include <linux/slab.h>
	12	#include <linux/spinlock.h>
	13	#include <linux/completion.h>
	14	#include <linux/buffer_head.h>
	15	#include <linux/mm.h>
	16	#include <linux/pagemap.h>
5c676f6d	17	#include <linux/gfs2_ondisk.h>
b3b94faa DT	18
b3b94faa DT	19	#include "gfs2.h"
5c676f6d SW	20	#include "lm_interface.h"
5c676f6d SW	21	#include "incore.h"
b3b94faa DT	22	#include "bmap.h"
	23	#include "glock.h"
	24	#include "inode.h"
	25	#include "ops_vm.h"
b3b94faa DT	26	#include "quota.h"
	27	#include "rgrp.h"
	28	#include "trans.h"
5c676f6d	29	#include "util.h"
b3b94faa DT	30
	31	static void pfault_be_greedy(struct gfs2_inode *ip)
	32	{
	33	unsigned int time;
	34
	35	spin_lock(&ip->i_spin);
	36	time = ip->i_greedy;
	37	ip->i_last_pfault = jiffies;
	38	spin_unlock(&ip->i_spin);
	39
feaa7bba	40	igrab(&ip->i_inode);
b3b94faa	41	if (gfs2_glock_be_greedy(ip->i_gl, time))
feaa7bba	42	iput(&ip->i_inode);
b3b94faa DT	43	}
	44
	45	static struct page gfs2_private_nopage(struct vm_area_struct area,
	46	unsigned long address, int *type)
	47	{
feaa7bba	48	struct gfs2_inode *ip = GFS2_I(area->vm_file->f_mapping->host);
b3b94faa	49	struct page *result;
b3b94faa DT	50
	51	set_bit(GIF_PAGED, &ip->i_flags);
	52
	53	result = filemap_nopage(area, address, type);
	54
	55	if (result && result != NOPAGE_OOM)
	56	pfault_be_greedy(ip);
	57
b3b94faa DT	58	return result;
	59	}
	60
	61	static int alloc_page_backing(struct gfs2_inode ip, struct page page)
	62	{
feaa7bba	63	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
b3b94faa	64	unsigned long index = page->index;
568f4c96 SW	65	uint64_t lblock = index << (PAGE_CACHE_SHIFT -
568f4c96 SW	66	sdp->sd_sb.sb_bsize_shift);
b3b94faa DT	67	unsigned int blocks = PAGE_CACHE_SIZE >> sdp->sd_sb.sb_bsize_shift;
	68	struct gfs2_alloc *al;
	69	unsigned int data_blocks, ind_blocks;
	70	unsigned int x;
	71	int error;
	72
	73	al = gfs2_alloc_get(ip);
	74
	75	error = gfs2_quota_lock(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
	76	if (error)
	77	goto out;
	78
	79	error = gfs2_quota_check(ip, ip->i_di.di_uid, ip->i_di.di_gid);
	80	if (error)
	81	goto out_gunlock_q;
	82
fd88de56	83	gfs2_write_calc_reserv(ip, PAGE_CACHE_SIZE, &data_blocks, &ind_blocks);
b3b94faa DT	84
	85	al->al_requested = data_blocks + ind_blocks;
	86
	87	error = gfs2_inplace_reserve(ip);
	88	if (error)
	89	goto out_gunlock_q;
	90
fd88de56	91	error = gfs2_trans_begin(sdp, al->al_rgd->rd_ri.ri_length +
b3b94faa DT	92	ind_blocks + RES_DINODE +
	93	RES_STATFS + RES_QUOTA, 0);
	94	if (error)
	95	goto out_ipres;
	96
	97	if (gfs2_is_stuffed(ip)) {
f25ef0c1	98	error = gfs2_unstuff_dinode(ip, NULL);
b3b94faa DT	99	if (error)
	100	goto out_trans;
	101	}
	102
	103	for (x = 0; x < blocks; ) {
	104	uint64_t dblock;
	105	unsigned int extlen;
	106	int new = 1;
	107
feaa7bba	108	error = gfs2_extent_map(&ip->i_inode, lblock, &new, &dblock, &extlen);
b3b94faa DT	109	if (error)
	110	goto out_trans;
	111
	112	lblock += extlen;
	113	x += extlen;
	114	}
	115
	116	gfs2_assert_warn(sdp, al->al_alloced);
	117
	118	out_trans:
	119	gfs2_trans_end(sdp);
	120
	121	out_ipres:
	122	gfs2_inplace_release(ip);
	123
	124	out_gunlock_q:
	125	gfs2_quota_unlock(ip);
	126
	127	out:
	128	gfs2_alloc_put(ip);
	129
	130	return error;
	131	}
	132
	133	static struct page gfs2_sharewrite_nopage(struct vm_area_struct area,
	134	unsigned long address, int *type)
	135	{
59a1cc6b SW	136	struct file *file = area->vm_file;
	137	struct gfs2_file *gf = file->private_data;
	138	struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
b3b94faa DT	139	struct gfs2_holder i_gh;
b3b94faa DT	140	struct page *result = NULL;
568f4c96 SW	141	unsigned long index = ((address - area->vm_start) >> PAGE_CACHE_SHIFT) +
568f4c96 SW	142	area->vm_pgoff;
b3b94faa DT	143	int alloc_required;
	144	int error;
	145
b3b94faa DT	146	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
	147	if (error)
	148	return NULL;
	149
b3b94faa DT	150	set_bit(GIF_PAGED, &ip->i_flags);
	151	set_bit(GIF_SW_PAGED, &ip->i_flags);
	152
59a1cc6b	153	error = gfs2_write_alloc_required(ip, (u64)index << PAGE_CACHE_SHIFT,
b3b94faa DT	154	PAGE_CACHE_SIZE, &alloc_required);
	155	if (error)
	156	goto out;
	157
59a1cc6b	158	set_bit(GFF_EXLOCK, &gf->f_flags);
b3b94faa	159	result = filemap_nopage(area, address, type);
59a1cc6b	160	clear_bit(GFF_EXLOCK, &gf->f_flags);
b3b94faa DT	161	if (!result \|\| result == NOPAGE_OOM)
	162	goto out;
	163
	164	if (alloc_required) {
	165	error = alloc_page_backing(ip, result);
	166	if (error) {
	167	page_cache_release(result);
	168	result = NULL;
	169	goto out;
	170	}
	171	set_page_dirty(result);
	172	}
	173
	174	pfault_be_greedy(ip);
59a1cc6b	175	out:
b3b94faa DT	176	gfs2_glock_dq_uninit(&i_gh);
	177
	178	return result;
	179	}
	180
	181	struct vm_operations_struct gfs2_vm_ops_private = {
	182	.nopage = gfs2_private_nopage,
	183	};
	184
	185	struct vm_operations_struct gfs2_vm_ops_sharewrite = {
	186	.nopage = gfs2_sharewrite_nopage,
	187	};
	188