[RFC PATCH 1/3] mm: shmem: add file length arg in shmem_get_folio() path
From: Baolin Wang
Date: Wed Jul 24 2024 - 03:09:56 EST
From: Daniel Gomez <da.gomez@xxxxxxxxxxx>
In preparation for large folio in the write and fallocate paths, add
file length argument in shmem_get_folio() path to be able to calculate
the folio order based on the file size. Use of order-0 (PAGE_SIZE) for
read, page cache read, and vm fault.
This enables high order folios in the write and fallocate path once the
folio order is calculated based on the length.
Signed-off-by: Daniel Gomez <da.gomez@xxxxxxxxxxx>
Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx>
---
fs/xfs/scrub/xfile.c | 6 +++---
fs/xfs/xfs_buf_mem.c | 3 ++-
include/linux/shmem_fs.h | 2 +-
mm/khugepaged.c | 3 ++-
mm/shmem.c | 28 ++++++++++++++++------------
mm/userfaultfd.c | 2 +-
6 files changed, 25 insertions(+), 19 deletions(-)
diff --git a/fs/xfs/scrub/xfile.c b/fs/xfs/scrub/xfile.c
index d848222f802b..d814d9d786d3 100644
--- a/fs/xfs/scrub/xfile.c
+++ b/fs/xfs/scrub/xfile.c
@@ -127,7 +127,7 @@ xfile_load(
unsigned int offset;
if (shmem_get_folio(inode, pos >> PAGE_SHIFT, &folio,
- SGP_READ) < 0)
+ SGP_READ, PAGE_SIZE) < 0)
break;
if (!folio) {
/*
@@ -197,7 +197,7 @@ xfile_store(
unsigned int offset;
if (shmem_get_folio(inode, pos >> PAGE_SHIFT, &folio,
- SGP_CACHE) < 0)
+ SGP_CACHE, PAGE_SIZE) < 0)
break;
if (filemap_check_wb_err(inode->i_mapping, 0)) {
folio_unlock(folio);
@@ -268,7 +268,7 @@ xfile_get_folio(
pflags = memalloc_nofs_save();
error = shmem_get_folio(inode, pos >> PAGE_SHIFT, &folio,
- (flags & XFILE_ALLOC) ? SGP_CACHE : SGP_READ);
+ (flags & XFILE_ALLOC) ? SGP_CACHE : SGP_READ, PAGE_SIZE);
memalloc_nofs_restore(pflags);
if (error)
return ERR_PTR(error);
diff --git a/fs/xfs/xfs_buf_mem.c b/fs/xfs/xfs_buf_mem.c
index 9bb2d24de709..784c81d35a1f 100644
--- a/fs/xfs/xfs_buf_mem.c
+++ b/fs/xfs/xfs_buf_mem.c
@@ -149,7 +149,8 @@ xmbuf_map_page(
return -ENOMEM;
}
- error = shmem_get_folio(inode, pos >> PAGE_SHIFT, &folio, SGP_CACHE);
+ error = shmem_get_folio(inode, pos >> PAGE_SHIFT, &folio, SGP_CACHE,
+ PAGE_SIZE);
if (error)
return error;
diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h
index 1564d7d3ca61..34beaca2f853 100644
--- a/include/linux/shmem_fs.h
+++ b/include/linux/shmem_fs.h
@@ -144,7 +144,7 @@ enum sgp_type {
};
int shmem_get_folio(struct inode *inode, pgoff_t index, struct folio **foliop,
- enum sgp_type sgp);
+ enum sgp_type sgp, size_t len);
struct folio *shmem_read_folio_gfp(struct address_space *mapping,
pgoff_t index, gfp_t gfp);
diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index a5ec03ef8722..3c9dbebbdf38 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -1867,7 +1867,8 @@ static int collapse_file(struct mm_struct *mm, unsigned long addr,
xas_unlock_irq(&xas);
/* swap in or instantiate fallocated page */
if (shmem_get_folio(mapping->host, index,
- &folio, SGP_NOALLOC)) {
+ &folio, SGP_NOALLOC,
+ PAGE_SIZE)) {
result = SCAN_FAIL;
goto xa_unlocked;
}
diff --git a/mm/shmem.c b/mm/shmem.c
index db8f74cac1a2..92ed09527682 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -980,7 +980,7 @@ static struct folio *shmem_get_partial_folio(struct inode *inode, pgoff_t index)
* (although in some cases this is just a waste of time).
*/
folio = NULL;
- shmem_get_folio(inode, index, &folio, SGP_READ);
+ shmem_get_folio(inode, index, &folio, SGP_READ, PAGE_SIZE);
return folio;
}
@@ -2094,7 +2094,7 @@ static int shmem_swapin_folio(struct inode *inode, pgoff_t index,
*/
static int shmem_get_folio_gfp(struct inode *inode, pgoff_t index,
struct folio **foliop, enum sgp_type sgp, gfp_t gfp,
- struct vm_fault *vmf, vm_fault_t *fault_type)
+ struct vm_fault *vmf, vm_fault_t *fault_type, size_t len)
{
struct vm_area_struct *vma = vmf ? vmf->vma : NULL;
struct mm_struct *fault_mm;
@@ -2297,10 +2297,10 @@ static int shmem_get_folio_gfp(struct inode *inode, pgoff_t index,
* Return: 0 if successful, else a negative error code.
*/
int shmem_get_folio(struct inode *inode, pgoff_t index, struct folio **foliop,
- enum sgp_type sgp)
+ enum sgp_type sgp, size_t len)
{
return shmem_get_folio_gfp(inode, index, foliop, sgp,
- mapping_gfp_mask(inode->i_mapping), NULL, NULL);
+ mapping_gfp_mask(inode->i_mapping), NULL, NULL, len);
}
EXPORT_SYMBOL_GPL(shmem_get_folio);
@@ -2395,7 +2395,7 @@ static vm_fault_t shmem_fault(struct vm_fault *vmf)
WARN_ON_ONCE(vmf->page != NULL);
err = shmem_get_folio_gfp(inode, vmf->pgoff, &folio, SGP_CACHE,
- gfp, vmf, &ret);
+ gfp, vmf, &ret, PAGE_SIZE);
if (err)
return vmf_error(err);
if (folio) {
@@ -2895,6 +2895,9 @@ shmem_write_begin(struct file *file, struct address_space *mapping,
struct folio *folio;
int ret = 0;
+ if (!mapping_large_folio_support(mapping))
+ len = min_t(size_t, len, PAGE_SIZE - offset_in_page(pos));
+
/* i_rwsem is held by caller */
if (unlikely(info->seals & (F_SEAL_GROW |
F_SEAL_WRITE | F_SEAL_FUTURE_WRITE))) {
@@ -2904,7 +2907,7 @@ shmem_write_begin(struct file *file, struct address_space *mapping,
return -EPERM;
}
- ret = shmem_get_folio(inode, index, &folio, SGP_WRITE);
+ ret = shmem_get_folio(inode, index, &folio, SGP_WRITE, len);
if (ret)
return ret;
@@ -2975,7 +2978,7 @@ static ssize_t shmem_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
break;
}
- error = shmem_get_folio(inode, index, &folio, SGP_READ);
+ error = shmem_get_folio(inode, index, &folio, SGP_READ, PAGE_SIZE);
if (error) {
if (error == -EINVAL)
error = 0;
@@ -3152,7 +3155,7 @@ static ssize_t shmem_file_splice_read(struct file *in, loff_t *ppos,
break;
error = shmem_get_folio(inode, *ppos / PAGE_SIZE, &folio,
- SGP_READ);
+ SGP_READ, PAGE_SIZE);
if (error) {
if (error == -EINVAL)
error = 0;
@@ -3339,7 +3342,8 @@ static long shmem_fallocate(struct file *file, int mode, loff_t offset,
error = -ENOMEM;
else
error = shmem_get_folio(inode, index, &folio,
- SGP_FALLOC);
+ SGP_FALLOC,
+ (end - index) << PAGE_SHIFT);
if (error) {
info->fallocend = undo_fallocend;
/* Remove the !uptodate folios we added */
@@ -3690,7 +3694,7 @@ static int shmem_symlink(struct mnt_idmap *idmap, struct inode *dir,
} else {
inode_nohighmem(inode);
inode->i_mapping->a_ops = &shmem_aops;
- error = shmem_get_folio(inode, 0, &folio, SGP_WRITE);
+ error = shmem_get_folio(inode, 0, &folio, SGP_WRITE, PAGE_SIZE);
if (error)
goto out_remove_offset;
inode->i_op = &shmem_symlink_inode_operations;
@@ -3736,7 +3740,7 @@ static const char *shmem_get_link(struct dentry *dentry, struct inode *inode,
return ERR_PTR(-ECHILD);
}
} else {
- error = shmem_get_folio(inode, 0, &folio, SGP_READ);
+ error = shmem_get_folio(inode, 0, &folio, SGP_READ, PAGE_SIZE);
if (error)
return ERR_PTR(error);
if (!folio)
@@ -5209,7 +5213,7 @@ struct folio *shmem_read_folio_gfp(struct address_space *mapping,
int error;
error = shmem_get_folio_gfp(inode, index, &folio, SGP_CACHE,
- gfp, NULL, NULL);
+ gfp, NULL, NULL, PAGE_SIZE);
if (error)
return ERR_PTR(error);
diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c
index e54e5c8907fa..c275e34c435a 100644
--- a/mm/userfaultfd.c
+++ b/mm/userfaultfd.c
@@ -391,7 +391,7 @@ static int mfill_atomic_pte_continue(pmd_t *dst_pmd,
struct page *page;
int ret;
- ret = shmem_get_folio(inode, pgoff, &folio, SGP_NOALLOC);
+ ret = shmem_get_folio(inode, pgoff, &folio, SGP_NOALLOC, PAGE_SIZE);
/* Our caller expects us to return -EFAULT if we failed to find folio */
if (ret == -ENOENT)
ret = -EFAULT;
--
2.39.3