+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0
-#ifndef NO_BCACHEFS_FS
-
-#include "bcachefs.h"
-#include "btree_iter.h"
-#include "extents.h"
-#include "fs-io.h"
-#include "fs-io-pagecache.h"
-#include "subvolume.h"
-
-#include <linux/pagevec.h>
-#include <linux/writeback.h>
-
-int bch2_filemap_get_contig_folios_d(struct address_space *mapping,
- loff_t start, u64 end,
- fgf_t fgp_flags, gfp_t gfp,
- folios *fs)
-{
- struct folio *f;
- u64 pos = start;
- int ret = 0;
-
- while (pos < end) {
- if ((u64) pos >= (u64) start + (1ULL << 20))
- fgp_flags &= ~FGP_CREAT;
-
- ret = darray_make_room_gfp(fs, 1, gfp & GFP_KERNEL);
- if (ret)
- break;
-
- f = __filemap_get_folio(mapping, pos >> PAGE_SHIFT, fgp_flags, gfp);
- if (IS_ERR_OR_NULL(f))
- break;
-
- BUG_ON(fs->nr && folio_pos(f) != pos);
-
- pos = folio_end_pos(f);
- darray_push(fs, f);
- }
-
- if (!fs->nr && !ret && (fgp_flags & FGP_CREAT))
- ret = -ENOMEM;
-
- return fs->nr ? 0 : ret;
-}
-
-/* pagecache_block must be held */
-int bch2_write_invalidate_inode_pages_range(struct address_space *mapping,
- loff_t start, loff_t end)
-{
- int ret;
-
- /*
- * XXX: the way this is currently implemented, we can spin if a process
- * is continually redirtying a specific page
- */
- do {
- if (!mapping->nrpages)
- return 0;
-
- ret = filemap_write_and_wait_range(mapping, start, end);
- if (ret)
- break;
-
- if (!mapping->nrpages)
- return 0;
-
- ret = invalidate_inode_pages2_range(mapping,
- start >> PAGE_SHIFT,
- end >> PAGE_SHIFT);
- } while (ret == -EBUSY);
-
- return ret;
-}
-
-#if 0
-/* Useful for debug tracing: */
-static const char * const bch2_folio_sector_states[] = {
-#define x(n) #n,
- BCH_FOLIO_SECTOR_STATE()
-#undef x
- NULL
-};
-#endif
-
-static inline enum bch_folio_sector_state
-folio_sector_dirty(enum bch_folio_sector_state state)
-{
- switch (state) {
- case SECTOR_unallocated:
- return SECTOR_dirty;
- case SECTOR_reserved:
- return SECTOR_dirty_reserved;
- default:
- return state;
- }
-}
-
-static inline enum bch_folio_sector_state
-folio_sector_undirty(enum bch_folio_sector_state state)
-{
- switch (state) {
- case SECTOR_dirty:
- return SECTOR_unallocated;
- case SECTOR_dirty_reserved:
- return SECTOR_reserved;
- default:
- return state;
- }
-}
-
-static inline enum bch_folio_sector_state
-folio_sector_reserve(enum bch_folio_sector_state state)
-{
- switch (state) {
- case SECTOR_unallocated:
- return SECTOR_reserved;
- case SECTOR_dirty:
- return SECTOR_dirty_reserved;
- default:
- return state;
- }
-}
-
-/* for newly allocated folios: */
-struct bch_folio *__bch2_folio_create(struct folio *folio, gfp_t gfp)
-{
- struct bch_folio *s;
-
- s = kzalloc(sizeof(*s) +
- sizeof(struct bch_folio_sector) *
- folio_sectors(folio), gfp);
- if (!s)
- return NULL;
-
- spin_lock_init(&s->lock);
- folio_attach_private(folio, s);
- return s;
-}
-
-struct bch_folio *bch2_folio_create(struct folio *folio, gfp_t gfp)
-{
- return bch2_folio(folio) ?: __bch2_folio_create(folio, gfp);
-}
-
-static unsigned bkey_to_sector_state(struct bkey_s_c k)
-{
- if (bkey_extent_is_reservation(k))
- return SECTOR_reserved;
- if (bkey_extent_is_allocation(k.k))
- return SECTOR_allocated;
- return SECTOR_unallocated;
-}
-
-static void __bch2_folio_set(struct folio *folio,
- unsigned pg_offset, unsigned pg_len,
- unsigned nr_ptrs, unsigned state)
-{
- struct bch_folio *s = bch2_folio(folio);
- unsigned i, sectors = folio_sectors(folio);
-
- BUG_ON(pg_offset >= sectors);
- BUG_ON(pg_offset + pg_len > sectors);
-
- spin_lock(&s->lock);
-
- for (i = pg_offset; i < pg_offset + pg_len; i++) {
- s->s[i].nr_replicas = nr_ptrs;
- bch2_folio_sector_set(folio, s, i, state);
- }
-
- if (i == sectors)
- s->uptodate = true;
-
- spin_unlock(&s->lock);
-}
-
-/*
- * Initialize bch_folio state (allocated/unallocated, nr_replicas) from the
- * extents btree:
- */
-int bch2_folio_set(struct bch_fs *c, subvol_inum inum,
- struct folio **fs, unsigned nr_folios)
-{
- struct btree_trans *trans;
- struct btree_iter iter;
- struct bkey_s_c k;
- struct bch_folio *s;
- u64 offset = folio_sector(fs[0]);
- unsigned folio_idx;
- u32 snapshot;
- bool need_set = false;
- int ret;
-
- for (folio_idx = 0; folio_idx < nr_folios; folio_idx++) {
- s = bch2_folio_create(fs[folio_idx], GFP_KERNEL);
- if (!s)
- return -ENOMEM;
-
- need_set |= !s->uptodate;
- }
-
- if (!need_set)
- return 0;
-
- folio_idx = 0;
- trans = bch2_trans_get(c);
-retry:
- bch2_trans_begin(trans);
-
- ret = bch2_subvolume_get_snapshot(trans, inum.subvol, &snapshot);
- if (ret)
- goto err;
-
- for_each_btree_key_norestart(trans, iter, BTREE_ID_extents,
- SPOS(inum.inum, offset, snapshot),
- BTREE_ITER_SLOTS, k, ret) {
- unsigned nr_ptrs = bch2_bkey_nr_ptrs_fully_allocated(k);
- unsigned state = bkey_to_sector_state(k);
-
- while (folio_idx < nr_folios) {
- struct folio *folio = fs[folio_idx];
- u64 folio_start = folio_sector(folio);
- u64 folio_end = folio_end_sector(folio);
- unsigned folio_offset = max(bkey_start_offset(k.k), folio_start) -
- folio_start;
- unsigned folio_len = min(k.k->p.offset, folio_end) -
- folio_offset - folio_start;
-
- BUG_ON(k.k->p.offset < folio_start);
- BUG_ON(bkey_start_offset(k.k) > folio_end);
-
- if (!bch2_folio(folio)->uptodate)
- __bch2_folio_set(folio, folio_offset, folio_len, nr_ptrs, state);
-
- if (k.k->p.offset < folio_end)
- break;
- folio_idx++;
- }
-
- if (folio_idx == nr_folios)
- break;
- }
-
- offset = iter.pos.offset;
- bch2_trans_iter_exit(trans, &iter);
-err:
- if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
- goto retry;
- bch2_trans_put(trans);
-
- return ret;
-}
-
-void bch2_bio_page_state_set(struct bio *bio, struct bkey_s_c k)
-{
- struct bvec_iter iter;
- struct folio_vec fv;
- unsigned nr_ptrs = k.k->type == KEY_TYPE_reflink_v
- ? 0 : bch2_bkey_nr_ptrs_fully_allocated(k);
- unsigned state = bkey_to_sector_state(k);
-
- bio_for_each_folio(fv, bio, iter)
- __bch2_folio_set(fv.fv_folio,
- fv.fv_offset >> 9,
- fv.fv_len >> 9,
- nr_ptrs, state);
-}
-
-void bch2_mark_pagecache_unallocated(struct bch_inode_info *inode,
- u64 start, u64 end)
-{
- pgoff_t index = start >> PAGE_SECTORS_SHIFT;
- pgoff_t end_index = (end - 1) >> PAGE_SECTORS_SHIFT;
- struct folio_batch fbatch;
- unsigned i, j;
-
- if (end <= start)
- return;
-
- folio_batch_init(&fbatch);
-
- while (filemap_get_folios(inode->v.i_mapping,
- &index, end_index, &fbatch)) {
- for (i = 0; i < folio_batch_count(&fbatch); i++) {
- struct folio *folio = fbatch.folios[i];
- u64 folio_start = folio_sector(folio);
- u64 folio_end = folio_end_sector(folio);
- unsigned folio_offset = max(start, folio_start) - folio_start;
- unsigned folio_len = min(end, folio_end) - folio_offset - folio_start;
- struct bch_folio *s;
-
- BUG_ON(end <= folio_start);
-
- folio_lock(folio);
- s = bch2_folio(folio);
-
- if (s) {
- spin_lock(&s->lock);
- for (j = folio_offset; j < folio_offset + folio_len; j++)
- s->s[j].nr_replicas = 0;
- spin_unlock(&s->lock);
- }
-
- folio_unlock(folio);
- }
- folio_batch_release(&fbatch);
- cond_resched();
- }
-}
-
-void bch2_mark_pagecache_reserved(struct bch_inode_info *inode,
- u64 start, u64 end)
-{
- struct bch_fs *c = inode->v.i_sb->s_fs_info;
- pgoff_t index = start >> PAGE_SECTORS_SHIFT;
- pgoff_t end_index = (end - 1) >> PAGE_SECTORS_SHIFT;
- struct folio_batch fbatch;
- s64 i_sectors_delta = 0;
- unsigned i, j;
-
- if (end <= start)
- return;
-
- folio_batch_init(&fbatch);
-
- while (filemap_get_folios(inode->v.i_mapping,
- &index, end_index, &fbatch)) {
- for (i = 0; i < folio_batch_count(&fbatch); i++) {
- struct folio *folio = fbatch.folios[i];
- u64 folio_start = folio_sector(folio);
- u64 folio_end = folio_end_sector(folio);
- unsigned folio_offset = max(start, folio_start) - folio_start;
- unsigned folio_len = min(end, folio_end) - folio_offset - folio_start;
- struct bch_folio *s;
-
- BUG_ON(end <= folio_start);
-
- folio_lock(folio);
- s = bch2_folio(folio);
-
- if (s) {
- spin_lock(&s->lock);
- for (j = folio_offset; j < folio_offset + folio_len; j++) {
- i_sectors_delta -= s->s[j].state == SECTOR_dirty;
- bch2_folio_sector_set(folio, s, j,
- folio_sector_reserve(s->s[j].state));
- }
- spin_unlock(&s->lock);
- }
-
- folio_unlock(folio);
- }
- folio_batch_release(&fbatch);
- cond_resched();
- }
-
- bch2_i_sectors_acct(c, inode, NULL, i_sectors_delta);
-}
-
-static inline unsigned sectors_to_reserve(struct bch_folio_sector *s,
- unsigned nr_replicas)
-{
- return max(0, (int) nr_replicas -
- s->nr_replicas -
- s->replicas_reserved);
-}
-
-int bch2_get_folio_disk_reservation(struct bch_fs *c,
- struct bch_inode_info *inode,
- struct folio *folio, bool check_enospc)
-{
- struct bch_folio *s = bch2_folio_create(folio, 0);
- unsigned nr_replicas = inode_nr_replicas(c, inode);
- struct disk_reservation disk_res = { 0 };
- unsigned i, sectors = folio_sectors(folio), disk_res_sectors = 0;
- int ret;
-
- if (!s)
- return -ENOMEM;
-
- for (i = 0; i < sectors; i++)
- disk_res_sectors += sectors_to_reserve(&s->s[i], nr_replicas);
-
- if (!disk_res_sectors)
- return 0;
-
- ret = bch2_disk_reservation_get(c, &disk_res,
- disk_res_sectors, 1,
- !check_enospc
- ? BCH_DISK_RESERVATION_NOFAIL
- : 0);
- if (unlikely(ret))
- return ret;
-
- for (i = 0; i < sectors; i++)
- s->s[i].replicas_reserved +=
- sectors_to_reserve(&s->s[i], nr_replicas);
-
- return 0;
-}
-
-void bch2_folio_reservation_put(struct bch_fs *c,
- struct bch_inode_info *inode,
- struct bch2_folio_reservation *res)
-{
- bch2_disk_reservation_put(c, &res->disk);
- bch2_quota_reservation_put(c, inode, &res->quota);
-}
-
-int bch2_folio_reservation_get(struct bch_fs *c,
- struct bch_inode_info *inode,
- struct folio *folio,
- struct bch2_folio_reservation *res,
- unsigned offset, unsigned len)
-{
- struct bch_folio *s = bch2_folio_create(folio, 0);
- unsigned i, disk_sectors = 0, quota_sectors = 0;
- int ret;
-
- if (!s)
- return -ENOMEM;
-
- BUG_ON(!s->uptodate);
-
- for (i = round_down(offset, block_bytes(c)) >> 9;
- i < round_up(offset + len, block_bytes(c)) >> 9;
- i++) {
- disk_sectors += sectors_to_reserve(&s->s[i],
- res->disk.nr_replicas);
- quota_sectors += s->s[i].state == SECTOR_unallocated;
- }
-
- if (disk_sectors) {
- ret = bch2_disk_reservation_add(c, &res->disk, disk_sectors, 0);
- if (unlikely(ret))
- return ret;
- }
-
- if (quota_sectors) {
- ret = bch2_quota_reservation_add(c, inode, &res->quota,
- quota_sectors, true);
- if (unlikely(ret)) {
- struct disk_reservation tmp = {
- .sectors = disk_sectors
- };
-
- bch2_disk_reservation_put(c, &tmp);
- res->disk.sectors -= disk_sectors;
- return ret;
- }
- }
-
- return 0;
-}
-
-static void bch2_clear_folio_bits(struct folio *folio)
-{
- struct bch_inode_info *inode = to_bch_ei(folio->mapping->host);
- struct bch_fs *c = inode->v.i_sb->s_fs_info;
- struct bch_folio *s = bch2_folio(folio);
- struct disk_reservation disk_res = { 0 };
- int i, sectors = folio_sectors(folio), dirty_sectors = 0;
-
- if (!s)
- return;
-
- EBUG_ON(!folio_test_locked(folio));
- EBUG_ON(folio_test_writeback(folio));
-
- for (i = 0; i < sectors; i++) {
- disk_res.sectors += s->s[i].replicas_reserved;
- s->s[i].replicas_reserved = 0;
-
- dirty_sectors -= s->s[i].state == SECTOR_dirty;
- bch2_folio_sector_set(folio, s, i, folio_sector_undirty(s->s[i].state));
- }
-
- bch2_disk_reservation_put(c, &disk_res);
-
- bch2_i_sectors_acct(c, inode, NULL, dirty_sectors);
-
- bch2_folio_release(folio);
-}
-
-void bch2_set_folio_dirty(struct bch_fs *c,
- struct bch_inode_info *inode,
- struct folio *folio,
- struct bch2_folio_reservation *res,
- unsigned offset, unsigned len)
-{
- struct bch_folio *s = bch2_folio(folio);
- unsigned i, dirty_sectors = 0;
-
- WARN_ON((u64) folio_pos(folio) + offset + len >
- round_up((u64) i_size_read(&inode->v), block_bytes(c)));
-
- BUG_ON(!s->uptodate);
-
- spin_lock(&s->lock);
-
- for (i = round_down(offset, block_bytes(c)) >> 9;
- i < round_up(offset + len, block_bytes(c)) >> 9;
- i++) {
- unsigned sectors = sectors_to_reserve(&s->s[i],
- res->disk.nr_replicas);
-
- /*
- * This can happen if we race with the error path in
- * bch2_writepage_io_done():
- */
- sectors = min_t(unsigned, sectors, res->disk.sectors);
-
- s->s[i].replicas_reserved += sectors;
- res->disk.sectors -= sectors;
-
- dirty_sectors += s->s[i].state == SECTOR_unallocated;
-
- bch2_folio_sector_set(folio, s, i, folio_sector_dirty(s->s[i].state));
- }
-
- spin_unlock(&s->lock);
-
- bch2_i_sectors_acct(c, inode, &res->quota, dirty_sectors);
-
- if (!folio_test_dirty(folio))
- filemap_dirty_folio(inode->v.i_mapping, folio);
-}
-
-vm_fault_t bch2_page_fault(struct vm_fault *vmf)
-{
- struct file *file = vmf->vma->vm_file;
- struct address_space *mapping = file->f_mapping;
- struct address_space *fdm = faults_disabled_mapping();
- struct bch_inode_info *inode = file_bch_inode(file);
- vm_fault_t ret;
-
- if (fdm == mapping)
- return VM_FAULT_SIGBUS;
-
- /* Lock ordering: */
- if (fdm > mapping) {
- struct bch_inode_info *fdm_host = to_bch_ei(fdm->host);
-
- if (bch2_pagecache_add_tryget(inode))
- goto got_lock;
-
- bch2_pagecache_block_put(fdm_host);
-
- bch2_pagecache_add_get(inode);
- bch2_pagecache_add_put(inode);
-
- bch2_pagecache_block_get(fdm_host);
-
- /* Signal that lock has been dropped: */
- set_fdm_dropped_locks();
- return VM_FAULT_SIGBUS;
- }
-
- bch2_pagecache_add_get(inode);
-got_lock:
- ret = filemap_fault(vmf);
- bch2_pagecache_add_put(inode);
-
- return ret;
-}
-
-vm_fault_t bch2_page_mkwrite(struct vm_fault *vmf)
-{
- struct folio *folio = page_folio(vmf->page);
- struct file *file = vmf->vma->vm_file;
- struct bch_inode_info *inode = file_bch_inode(file);
- struct address_space *mapping = file->f_mapping;
- struct bch_fs *c = inode->v.i_sb->s_fs_info;
- struct bch2_folio_reservation res;
- unsigned len;
- loff_t isize;
- vm_fault_t ret;
-
- bch2_folio_reservation_init(c, inode, &res);
-
- sb_start_pagefault(inode->v.i_sb);
- file_update_time(file);
-
- /*
- * Not strictly necessary, but helps avoid dio writes livelocking in
- * bch2_write_invalidate_inode_pages_range() - can drop this if/when we get
- * a bch2_write_invalidate_inode_pages_range() that works without dropping
- * page lock before invalidating page
- */
- bch2_pagecache_add_get(inode);
-
- folio_lock(folio);
- isize = i_size_read(&inode->v);
-
- if (folio->mapping != mapping || folio_pos(folio) >= isize) {
- folio_unlock(folio);
- ret = VM_FAULT_NOPAGE;
- goto out;
- }
-
- len = min_t(loff_t, folio_size(folio), isize - folio_pos(folio));
-
- if (bch2_folio_set(c, inode_inum(inode), &folio, 1) ?:
- bch2_folio_reservation_get(c, inode, folio, &res, 0, len)) {
- folio_unlock(folio);
- ret = VM_FAULT_SIGBUS;
- goto out;
- }
-
- bch2_set_folio_dirty(c, inode, folio, &res, 0, len);
- bch2_folio_reservation_put(c, inode, &res);
-
- folio_wait_stable(folio);
- ret = VM_FAULT_LOCKED;
-out:
- bch2_pagecache_add_put(inode);
- sb_end_pagefault(inode->v.i_sb);
-
- return ret;
-}
-
-void bch2_invalidate_folio(struct folio *folio, size_t offset, size_t length)
-{
- if (offset || length < folio_size(folio))
- return;
-
- bch2_clear_folio_bits(folio);
-}
-
-bool bch2_release_folio(struct folio *folio, gfp_t gfp_mask)
-{
- if (folio_test_dirty(folio) || folio_test_writeback(folio))
- return false;
-
- bch2_clear_folio_bits(folio);
- return true;
-}
-
-/* fseek: */
-
-static int folio_data_offset(struct folio *folio, loff_t pos,
- unsigned min_replicas)
-{
- struct bch_folio *s = bch2_folio(folio);
- unsigned i, sectors = folio_sectors(folio);
-
- if (s)
- for (i = folio_pos_to_s(folio, pos); i < sectors; i++)
- if (s->s[i].state >= SECTOR_dirty &&
- s->s[i].nr_replicas + s->s[i].replicas_reserved >= min_replicas)
- return i << SECTOR_SHIFT;
-
- return -1;
-}
-
-loff_t bch2_seek_pagecache_data(struct inode *vinode,
- loff_t start_offset,
- loff_t end_offset,
- unsigned min_replicas,
- bool nonblock)
-{
- struct folio_batch fbatch;
- pgoff_t start_index = start_offset >> PAGE_SHIFT;
- pgoff_t end_index = end_offset >> PAGE_SHIFT;
- pgoff_t index = start_index;
- unsigned i;
- loff_t ret;
- int offset;
-
- folio_batch_init(&fbatch);
-
- while (filemap_get_folios(vinode->i_mapping,
- &index, end_index, &fbatch)) {
- for (i = 0; i < folio_batch_count(&fbatch); i++) {
- struct folio *folio = fbatch.folios[i];
-
- if (!nonblock) {
- folio_lock(folio);
- } else if (!folio_trylock(folio)) {
- folio_batch_release(&fbatch);
- return -EAGAIN;
- }
-
- offset = folio_data_offset(folio,
- max(folio_pos(folio), start_offset),
- min_replicas);
- if (offset >= 0) {
- ret = clamp(folio_pos(folio) + offset,
- start_offset, end_offset);
- folio_unlock(folio);
- folio_batch_release(&fbatch);
- return ret;
- }
- folio_unlock(folio);
- }
- folio_batch_release(&fbatch);
- cond_resched();
- }
-
- return end_offset;
-}
-
-/*
- * Search for a hole in a folio.
- *
- * The filemap layer returns -ENOENT if no folio exists, so reuse the same error
- * code to indicate a pagecache hole exists at the returned offset. Otherwise
- * return 0 if the folio is filled with data, or an error code. This function
- * can return -EAGAIN if nonblock is specified.
- */
-static int folio_hole_offset(struct address_space *mapping, loff_t *offset,
- unsigned min_replicas, bool nonblock)
-{
- struct folio *folio;
- struct bch_folio *s;
- unsigned i, sectors;
- int ret = -ENOENT;
-
- folio = __filemap_get_folio(mapping, *offset >> PAGE_SHIFT,
- FGP_LOCK|(nonblock ? FGP_NOWAIT : 0), 0);
- if (IS_ERR(folio))
- return PTR_ERR(folio);
-
- s = bch2_folio(folio);
- if (!s)
- goto unlock;
-
- sectors = folio_sectors(folio);
- for (i = folio_pos_to_s(folio, *offset); i < sectors; i++)
- if (s->s[i].state < SECTOR_dirty ||
- s->s[i].nr_replicas + s->s[i].replicas_reserved < min_replicas) {
- *offset = max(*offset,
- folio_pos(folio) + (i << SECTOR_SHIFT));
- goto unlock;
- }
-
- *offset = folio_end_pos(folio);
- ret = 0;
-unlock:
- folio_unlock(folio);
- folio_put(folio);
- return ret;
-}
-
-loff_t bch2_seek_pagecache_hole(struct inode *vinode,
- loff_t start_offset,
- loff_t end_offset,
- unsigned min_replicas,
- bool nonblock)
-{
- struct address_space *mapping = vinode->i_mapping;
- loff_t offset = start_offset;
- loff_t ret = 0;
-
- while (!ret && offset < end_offset)
- ret = folio_hole_offset(mapping, &offset, min_replicas, nonblock);
-
- if (ret && ret != -ENOENT)
- return ret;
- return min(offset, end_offset);
-}
-
-int bch2_clamp_data_hole(struct inode *inode,
- u64 *hole_start,
- u64 *hole_end,
- unsigned min_replicas,
- bool nonblock)
-{
- loff_t ret;
-
- ret = bch2_seek_pagecache_hole(inode,
- *hole_start << 9, *hole_end << 9, min_replicas, nonblock) >> 9;
- if (ret < 0)
- return ret;
-
- *hole_start = ret;
-
- if (*hole_start == *hole_end)
- return 0;
-
- ret = bch2_seek_pagecache_data(inode,
- *hole_start << 9, *hole_end << 9, min_replicas, nonblock) >> 9;
- if (ret < 0)
- return ret;
-
- *hole_end = ret;
- return 0;
-}
-
-#endif /* NO_BCACHEFS_FS */
projects / bcachefs-tools-debian / blobdiff