David Howells 2021-08-11 14:22:11 +01:00
parent 78525c74d9
commit 255ed63638
2 changed files with 174 additions and 209 deletions

View File

@ -103,13 +103,13 @@ struct afs_lookup_cookie {
};
/*
* Drop the refs that we're holding on the pages we were reading into. We've
* Drop the refs that we're holding on the folios we were reading into. We've
* got refs on the first nr_pages pages.
*/
static void afs_dir_read_cleanup(struct afs_read *req)
{
struct address_space *mapping = req->vnode->vfs_inode.i_mapping;
struct page *page;
struct folio *folio;
pgoff_t last = req->nr_pages - 1;
XA_STATE(xas, &mapping->i_pages, 0);
@ -118,65 +118,56 @@ static void afs_dir_read_cleanup(struct afs_read *req)
return;
rcu_read_lock();
xas_for_each(&xas, page, last) {
if (xas_retry(&xas, page))
xas_for_each(&xas, folio, last) {
if (xas_retry(&xas, folio))
continue;
BUG_ON(xa_is_value(page));
BUG_ON(PageCompound(page));
ASSERTCMP(page->mapping, ==, mapping);
BUG_ON(xa_is_value(folio));
ASSERTCMP(folio_file_mapping(folio), ==, mapping);
put_page(page);
folio_put(folio);
}
rcu_read_unlock();
}
/*
* check that a directory page is valid
* check that a directory folio is valid
*/
static bool afs_dir_check_page(struct afs_vnode *dvnode, struct page *page,
loff_t i_size)
static bool afs_dir_check_folio(struct afs_vnode *dvnode, struct folio *folio,
loff_t i_size)
{
struct afs_xdr_dir_page *dbuf;
loff_t latter, off;
int tmp, qty;
union afs_xdr_dir_block *block;
size_t offset, size;
loff_t pos;
/* Determine how many magic numbers there should be in this page, but
/* Determine how many magic numbers there should be in this folio, but
* we must take care because the directory may change size under us.
*/
off = page_offset(page);
if (i_size <= off)
pos = folio_pos(folio);
if (i_size <= pos)
goto checked;
latter = i_size - off;
if (latter >= PAGE_SIZE)
qty = PAGE_SIZE;
else
qty = latter;
qty /= sizeof(union afs_xdr_dir_block);
/* check them */
dbuf = kmap_atomic(page);
for (tmp = 0; tmp < qty; tmp++) {
if (dbuf->blocks[tmp].hdr.magic != AFS_DIR_MAGIC) {
printk("kAFS: %s(%lx): bad magic %d/%d is %04hx\n",
__func__, dvnode->vfs_inode.i_ino, tmp, qty,
ntohs(dbuf->blocks[tmp].hdr.magic));
trace_afs_dir_check_failed(dvnode, off, i_size);
kunmap(page);
size = min_t(loff_t, folio_size(folio), i_size - pos);
for (offset = 0; offset < size; offset += sizeof(*block)) {
block = kmap_local_folio(folio, offset);
if (block->hdr.magic != AFS_DIR_MAGIC) {
printk("kAFS: %s(%lx): [%llx] bad magic %zx/%zx is %04hx\n",
__func__, dvnode->vfs_inode.i_ino,
pos, offset, size, ntohs(block->hdr.magic));
trace_afs_dir_check_failed(dvnode, pos + offset, i_size);
kunmap_local(block);
trace_afs_file_error(dvnode, -EIO, afs_file_error_dir_bad_magic);
goto error;
}
/* Make sure each block is NUL terminated so we can reasonably
* use string functions on it. The filenames in the page
* use string functions on it. The filenames in the folio
* *should* be NUL-terminated anyway.
*/
((u8 *)&dbuf->blocks[tmp])[AFS_DIR_BLOCK_SIZE - 1] = 0;
((u8 *)block)[AFS_DIR_BLOCK_SIZE - 1] = 0;
kunmap_local(block);
}
kunmap_atomic(dbuf);
checked:
afs_stat_v(dvnode, n_read_dir);
return true;
@ -190,11 +181,11 @@ error:
*/
static void afs_dir_dump(struct afs_vnode *dvnode, struct afs_read *req)
{
struct afs_xdr_dir_page *dbuf;
union afs_xdr_dir_block *block;
struct address_space *mapping = dvnode->vfs_inode.i_mapping;
struct page *page;
unsigned int i, qty = PAGE_SIZE / sizeof(union afs_xdr_dir_block);
struct folio *folio;
pgoff_t last = req->nr_pages - 1;
size_t offset, size;
XA_STATE(xas, &mapping->i_pages, 0);
@ -205,30 +196,28 @@ static void afs_dir_dump(struct afs_vnode *dvnode, struct afs_read *req)
req->pos, req->nr_pages,
req->iter->iov_offset, iov_iter_count(req->iter));
xas_for_each(&xas, page, last) {
if (xas_retry(&xas, page))
xas_for_each(&xas, folio, last) {
if (xas_retry(&xas, folio))
continue;
BUG_ON(PageCompound(page));
BUG_ON(page->mapping != mapping);
BUG_ON(folio_file_mapping(folio) != mapping);
dbuf = kmap_atomic(page);
for (i = 0; i < qty; i++) {
union afs_xdr_dir_block *block = &dbuf->blocks[i];
pr_warn("[%02lx] %32phN\n", page->index * qty + i, block);
size = min_t(loff_t, folio_size(folio), req->actual_len - folio_pos(folio));
for (offset = 0; offset < size; offset += sizeof(*block)) {
block = kmap_local_folio(folio, offset);
pr_warn("[%02lx] %32phN\n", folio_index(folio) + offset, block);
kunmap_local(block);
}
kunmap_atomic(dbuf);
}
}
/*
* Check all the pages in a directory. All the pages are held pinned.
* Check all the blocks in a directory. All the folios are held pinned.
*/
static int afs_dir_check(struct afs_vnode *dvnode, struct afs_read *req)
{
struct address_space *mapping = dvnode->vfs_inode.i_mapping;
struct page *page;
struct folio *folio;
pgoff_t last = req->nr_pages - 1;
int ret = 0;
@ -238,14 +227,13 @@ static int afs_dir_check(struct afs_vnode *dvnode, struct afs_read *req)
return 0;
rcu_read_lock();
xas_for_each(&xas, page, last) {
if (xas_retry(&xas, page))
xas_for_each(&xas, folio, last) {
if (xas_retry(&xas, folio))
continue;
BUG_ON(PageCompound(page));
BUG_ON(page->mapping != mapping);
BUG_ON(folio_file_mapping(folio) != mapping);
if (!afs_dir_check_page(dvnode, page, req->file_size)) {
if (!afs_dir_check_folio(dvnode, folio, req->actual_len)) {
afs_dir_dump(dvnode, req);
ret = -EIO;
break;
@ -274,15 +262,16 @@ static int afs_dir_open(struct inode *inode, struct file *file)
/*
* Read the directory into the pagecache in one go, scrubbing the previous
* contents. The list of pages is returned, pinning them so that they don't
* contents. The list of folios is returned, pinning them so that they don't
* get reclaimed during the iteration.
*/
static struct afs_read *afs_read_dir(struct afs_vnode *dvnode, struct key *key)
__acquires(&dvnode->validate_lock)
{
struct address_space *mapping = dvnode->vfs_inode.i_mapping;
struct afs_read *req;
loff_t i_size;
int nr_pages, i, n;
int nr_pages, i;
int ret;
_enter("");
@ -320,43 +309,30 @@ expand:
req->iter = &req->def_iter;
/* Fill in any gaps that we might find where the memory reclaimer has
* been at work and pin all the pages. If there are any gaps, we will
* been at work and pin all the folios. If there are any gaps, we will
* need to reread the entire directory contents.
*/
i = req->nr_pages;
while (i < nr_pages) {
struct page *pages[8], *page;
n = find_get_pages_contig(dvnode->vfs_inode.i_mapping, i,
min_t(unsigned int, nr_pages - i,
ARRAY_SIZE(pages)),
pages);
_debug("find %u at %u/%u", n, i, nr_pages);
if (n == 0) {
gfp_t gfp = dvnode->vfs_inode.i_mapping->gfp_mask;
struct folio *folio;
folio = filemap_get_folio(mapping, i);
if (!folio) {
if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
afs_stat_v(dvnode, n_inval);
ret = -ENOMEM;
page = __page_cache_alloc(gfp);
if (!page)
folio = __filemap_get_folio(mapping,
i, FGP_LOCK | FGP_CREAT,
mapping->gfp_mask);
if (!folio)
goto error;
ret = add_to_page_cache_lru(page,
dvnode->vfs_inode.i_mapping,
i, gfp);
if (ret < 0)
goto error;
attach_page_private(page, (void *)1);
unlock_page(page);
req->nr_pages++;
i++;
} else {
req->nr_pages += n;
i += n;
folio_attach_private(folio, (void *)1);
folio_unlock(folio);
}
req->nr_pages += folio_nr_pages(folio);
i += folio_nr_pages(folio);
}
/* If we're going to reload, we need to lock all the pages to prevent
@ -424,7 +400,7 @@ static int afs_dir_iterate_block(struct afs_vnode *dvnode,
size_t nlen;
int tmp;
_enter("%u,%x,%p,,",(unsigned)ctx->pos,blkoff,block);
_enter("%llx,%x", ctx->pos, blkoff);
curr = (ctx->pos - blkoff) / sizeof(union afs_xdr_dirent);
@ -513,12 +489,10 @@ static int afs_dir_iterate(struct inode *dir, struct dir_context *ctx,
struct key *key, afs_dataversion_t *_dir_version)
{
struct afs_vnode *dvnode = AFS_FS_I(dir);
struct afs_xdr_dir_page *dbuf;
union afs_xdr_dir_block *dblock;
struct afs_read *req;
struct page *page;
unsigned blkoff, limit;
void __rcu **slot;
struct folio *folio;
unsigned offset, size;
int ret;
_enter("{%lu},%u,,", dir->i_ino, (unsigned)ctx->pos);
@ -540,43 +514,30 @@ static int afs_dir_iterate(struct inode *dir, struct dir_context *ctx,
/* walk through the blocks in sequence */
ret = 0;
while (ctx->pos < req->actual_len) {
blkoff = ctx->pos & ~(sizeof(union afs_xdr_dir_block) - 1);
/* Fetch the appropriate page from the directory and re-add it
/* Fetch the appropriate folio from the directory and re-add it
* to the LRU. We have all the pages pinned with an extra ref.
*/
rcu_read_lock();
page = NULL;
slot = radix_tree_lookup_slot(&dvnode->vfs_inode.i_mapping->i_pages,
blkoff / PAGE_SIZE);
if (slot)
page = radix_tree_deref_slot(slot);
rcu_read_unlock();
if (!page) {
folio = __filemap_get_folio(dir->i_mapping, ctx->pos / PAGE_SIZE,
FGP_ACCESSED, 0);
if (!folio) {
ret = afs_bad(dvnode, afs_file_error_dir_missing_page);
break;
}
mark_page_accessed(page);
limit = blkoff & ~(PAGE_SIZE - 1);
offset = round_down(ctx->pos, sizeof(*dblock)) - folio_file_pos(folio);
size = min_t(loff_t, folio_size(folio),
req->actual_len - folio_file_pos(folio));
dbuf = kmap(page);
/* deal with the individual blocks stashed on this page */
do {
dblock = &dbuf->blocks[(blkoff % PAGE_SIZE) /
sizeof(union afs_xdr_dir_block)];
ret = afs_dir_iterate_block(dvnode, ctx, dblock, blkoff);
if (ret != 1) {
kunmap(page);
dblock = kmap_local_folio(folio, offset);
ret = afs_dir_iterate_block(dvnode, ctx, dblock,
folio_file_pos(folio) + offset);
kunmap_local(dblock);
if (ret != 1)
goto out;
}
blkoff += sizeof(union afs_xdr_dir_block);
} while (offset += sizeof(*dblock), offset < size);
} while (ctx->pos < dir->i_size && blkoff < limit);
kunmap(page);
ret = 0;
}
@ -2037,42 +1998,42 @@ error:
}
/*
* Release a directory page and clean up its private state if it's not busy
* - return true if the page can now be released, false if not
* Release a directory folio and clean up its private state if it's not busy
* - return true if the folio can now be released, false if not
*/
static int afs_dir_releasepage(struct page *page, gfp_t gfp_flags)
static int afs_dir_releasepage(struct page *subpage, gfp_t gfp_flags)
{
struct afs_vnode *dvnode = AFS_FS_I(page->mapping->host);
struct folio *folio = page_folio(subpage);
struct afs_vnode *dvnode = AFS_FS_I(folio_inode(folio));
_enter("{{%llx:%llu}[%lu]}", dvnode->fid.vid, dvnode->fid.vnode, page->index);
_enter("{{%llx:%llu}[%lu]}", dvnode->fid.vid, dvnode->fid.vnode, folio_index(folio));
detach_page_private(page);
folio_detach_private(folio);
/* The directory will need reloading. */
if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
afs_stat_v(dvnode, n_relpg);
return 1;
return true;
}
/*
* invalidate part or all of a page
* - release a page and clean up its private data if offset is 0 (indicating
* the entire page)
* Invalidate part or all of a folio.
*/
static void afs_dir_invalidatepage(struct page *page, unsigned int offset,
static void afs_dir_invalidatepage(struct page *subpage, unsigned int offset,
unsigned int length)
{
struct afs_vnode *dvnode = AFS_FS_I(page->mapping->host);
struct folio *folio = page_folio(subpage);
struct afs_vnode *dvnode = AFS_FS_I(folio_inode(folio));
_enter("{%lu},%u,%u", page->index, offset, length);
_enter("{%lu},%u,%u", folio_index(folio), offset, length);
BUG_ON(!PageLocked(page));
BUG_ON(!folio_test_locked(folio));
/* The directory will need reloading. */
if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
afs_stat_v(dvnode, n_inval);
/* we clean up only if the entire page is being invalidated */
if (offset == 0 && length == thp_size(page))
detach_page_private(page);
/* we clean up only if the entire folio is being invalidated */
if (offset == 0 && length == folio_size(folio))
folio_detach_private(folio);
}

View File

@ -104,6 +104,25 @@ static void afs_clear_contig_bits(union afs_xdr_dir_block *block,
block->hdr.bitmap[7] &= ~(u8)(mask >> 7 * 8);
}
/*
* Get a new directory folio.
*/
static struct folio *afs_dir_get_folio(struct afs_vnode *vnode, pgoff_t index)
{
struct address_space *mapping = vnode->vfs_inode.i_mapping;
struct folio *folio;
folio = __filemap_get_folio(mapping, index,
FGP_LOCK | FGP_ACCESSED | FGP_CREAT,
mapping->gfp_mask);
if (!folio)
clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);
else if (folio && !folio_test_private(folio))
folio_attach_private(folio, (void *)1);
return folio;
}
/*
* Scan a directory block looking for a dirent of the right name.
*/
@ -188,13 +207,11 @@ void afs_edit_dir_add(struct afs_vnode *vnode,
enum afs_edit_dir_reason why)
{
union afs_xdr_dir_block *meta, *block;
struct afs_xdr_dir_page *meta_page, *dir_page;
union afs_xdr_dirent *de;
struct page *page0, *page;
struct folio *folio0, *folio;
unsigned int need_slots, nr_blocks, b;
pgoff_t index;
loff_t i_size;
gfp_t gfp;
int slot;
_enter(",,{%d,%s},", name->len, name->name);
@ -206,10 +223,8 @@ void afs_edit_dir_add(struct afs_vnode *vnode,
return;
}
gfp = vnode->vfs_inode.i_mapping->gfp_mask;
page0 = find_or_create_page(vnode->vfs_inode.i_mapping, 0, gfp);
if (!page0) {
clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);
folio0 = afs_dir_get_folio(vnode, 0);
if (!folio0) {
_leave(" [fgp]");
return;
}
@ -217,42 +232,35 @@ void afs_edit_dir_add(struct afs_vnode *vnode,
/* Work out how many slots we're going to need. */
need_slots = afs_dir_calc_slots(name->len);
meta_page = kmap(page0);
meta = &meta_page->blocks[0];
meta = kmap_local_folio(folio0, 0);
if (i_size == 0)
goto new_directory;
nr_blocks = i_size / AFS_DIR_BLOCK_SIZE;
/* Find a block that has sufficient slots available. Each VM page
/* Find a block that has sufficient slots available. Each folio
* contains two or more directory blocks.
*/
for (b = 0; b < nr_blocks + 1; b++) {
/* If the directory extended into a new page, then we need to
* tack a new page on the end.
/* If the directory extended into a new folio, then we need to
* tack a new folio on the end.
*/
index = b / AFS_DIR_BLOCKS_PER_PAGE;
if (index == 0) {
page = page0;
dir_page = meta_page;
if (nr_blocks >= AFS_DIR_MAX_BLOCKS)
goto error;
if (index >= folio_nr_pages(folio0)) {
folio = afs_dir_get_folio(vnode, index);
if (!folio)
goto error;
} else {
if (nr_blocks >= AFS_DIR_MAX_BLOCKS)
goto error;
gfp = vnode->vfs_inode.i_mapping->gfp_mask;
page = find_or_create_page(vnode->vfs_inode.i_mapping,
index, gfp);
if (!page)
goto error;
if (!PagePrivate(page))
attach_page_private(page, (void *)1);
dir_page = kmap(page);
folio = folio0;
}
block = kmap_local_folio(folio, b * AFS_DIR_BLOCK_SIZE - folio_file_pos(folio));
/* Abandon the edit if we got a callback break. */
if (!test_bit(AFS_VNODE_DIR_VALID, &vnode->flags))
goto invalidated;
block = &dir_page->blocks[b % AFS_DIR_BLOCKS_PER_PAGE];
_debug("block %u: %2u %3u %u",
b,
(b < AFS_DIR_BLOCKS_WITH_CTR) ? meta->meta.alloc_ctrs[b] : 99,
@ -266,7 +274,7 @@ void afs_edit_dir_add(struct afs_vnode *vnode,
afs_set_i_size(vnode, (b + 1) * AFS_DIR_BLOCK_SIZE);
}
/* Only lower dir pages have a counter in the header. */
/* Only lower dir blocks have a counter in the header. */
if (b >= AFS_DIR_BLOCKS_WITH_CTR ||
meta->meta.alloc_ctrs[b] >= need_slots) {
/* We need to try and find one or more consecutive
@ -279,10 +287,10 @@ void afs_edit_dir_add(struct afs_vnode *vnode,
}
}
if (page != page0) {
unlock_page(page);
kunmap(page);
put_page(page);
kunmap_local(block);
if (folio != folio0) {
folio_unlock(folio);
folio_put(folio);
}
}
@ -298,8 +306,8 @@ new_directory:
i_size = AFS_DIR_BLOCK_SIZE;
afs_set_i_size(vnode, i_size);
slot = AFS_DIR_RESV_BLOCKS0;
page = page0;
block = meta;
folio = folio0;
block = kmap_local_folio(folio, 0);
nr_blocks = 1;
b = 0;
@ -318,10 +326,10 @@ found_space:
/* Adjust the bitmap. */
afs_set_contig_bits(block, slot, need_slots);
if (page != page0) {
unlock_page(page);
kunmap(page);
put_page(page);
kunmap_local(block);
if (folio != folio0) {
folio_unlock(folio);
folio_put(folio);
}
/* Adjust the allocation counter. */
@ -333,18 +341,19 @@ found_space:
_debug("Insert %s in %u[%u]", name->name, b, slot);
out_unmap:
unlock_page(page0);
kunmap(page0);
put_page(page0);
kunmap_local(meta);
folio_unlock(folio0);
folio_put(folio0);
_leave("");
return;
invalidated:
trace_afs_edit_dir(vnode, why, afs_edit_dir_create_inval, 0, 0, 0, 0, name->name);
clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);
if (page != page0) {
kunmap(page);
put_page(page);
kunmap_local(block);
if (folio != folio0) {
folio_unlock(folio);
folio_put(folio);
}
goto out_unmap;
@ -364,10 +373,9 @@ error:
void afs_edit_dir_remove(struct afs_vnode *vnode,
struct qstr *name, enum afs_edit_dir_reason why)
{
struct afs_xdr_dir_page *meta_page, *dir_page;
union afs_xdr_dir_block *meta, *block;
union afs_xdr_dirent *de;
struct page *page0, *page;
struct folio *folio0, *folio;
unsigned int need_slots, nr_blocks, b;
pgoff_t index;
loff_t i_size;
@ -384,9 +392,8 @@ void afs_edit_dir_remove(struct afs_vnode *vnode,
}
nr_blocks = i_size / AFS_DIR_BLOCK_SIZE;
page0 = find_lock_page(vnode->vfs_inode.i_mapping, 0);
if (!page0) {
clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);
folio0 = afs_dir_get_folio(vnode, 0);
if (!folio0) {
_leave(" [fgp]");
return;
}
@ -394,30 +401,27 @@ void afs_edit_dir_remove(struct afs_vnode *vnode,
/* Work out how many slots we're going to discard. */
need_slots = afs_dir_calc_slots(name->len);
meta_page = kmap(page0);
meta = &meta_page->blocks[0];
meta = kmap_local_folio(folio0, 0);
/* Find a page that has sufficient slots available. Each VM page
/* Find a block that has sufficient slots available. Each folio
* contains two or more directory blocks.
*/
for (b = 0; b < nr_blocks; b++) {
index = b / AFS_DIR_BLOCKS_PER_PAGE;
if (index != 0) {
page = find_lock_page(vnode->vfs_inode.i_mapping, index);
if (!page)
if (index >= folio_nr_pages(folio0)) {
folio = afs_dir_get_folio(vnode, index);
if (!folio)
goto error;
dir_page = kmap(page);
} else {
page = page0;
dir_page = meta_page;
folio = folio0;
}
block = kmap_local_folio(folio, b * AFS_DIR_BLOCK_SIZE - folio_file_pos(folio));
/* Abandon the edit if we got a callback break. */
if (!test_bit(AFS_VNODE_DIR_VALID, &vnode->flags))
goto invalidated;
block = &dir_page->blocks[b % AFS_DIR_BLOCKS_PER_PAGE];
if (b > AFS_DIR_BLOCKS_WITH_CTR ||
meta->meta.alloc_ctrs[b] <= AFS_DIR_SLOTS_PER_BLOCK - 1 - need_slots) {
slot = afs_dir_scan_block(block, name, b);
@ -425,10 +429,10 @@ void afs_edit_dir_remove(struct afs_vnode *vnode,
goto found_dirent;
}
if (page != page0) {
unlock_page(page);
kunmap(page);
put_page(page);
kunmap_local(block);
if (folio != folio0) {
folio_unlock(folio);
folio_put(folio);
}
}
@ -449,10 +453,10 @@ found_dirent:
/* Adjust the bitmap. */
afs_clear_contig_bits(block, slot, need_slots);
if (page != page0) {
unlock_page(page);
kunmap(page);
put_page(page);
kunmap_local(block);
if (folio != folio0) {
folio_unlock(folio);
folio_put(folio);
}
/* Adjust the allocation counter. */
@ -464,9 +468,9 @@ found_dirent:
_debug("Remove %s from %u[%u]", name->name, b, slot);
out_unmap:
unlock_page(page0);
kunmap(page0);
put_page(page0);
kunmap_local(meta);
folio_unlock(folio0);
folio_put(folio0);
_leave("");
return;
@ -474,10 +478,10 @@ invalidated:
trace_afs_edit_dir(vnode, why, afs_edit_dir_delete_inval,
0, 0, 0, 0, name->name);
clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);
if (page != page0) {
unlock_page(page);
kunmap(page);
put_page(page);
kunmap_local(block);
if (folio != folio0) {
folio_unlock(folio);
folio_put(folio);
}
goto out_unmap;