diff options
| author | Vivek Kasireddy <vivek.kasireddy@intel.com> | 2025-06-17 22:30:53 -0700 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2025-07-09 22:42:14 -0700 |
| commit | 986f5f2b4be3b7eab9ecd85c472d03a2191d6fc0 (patch) | |
| tree | 1a8be426356a2b12232678a16a757d9c22bf250a /fs/hugetlbfs | |
| parent | d29d64afa2b20d9bd210c01bfff78545675b5135 (diff) | |
mm/hugetlb: make hugetlb_reserve_pages() return nr of entries updated
Patch series "mm/memfd: Reserve hugetlb folios before allocation", v4.
There are cases when we try to pin a folio but discover that it has not
been faulted-in. So, we try to allocate it in memfd_alloc_folio() but the
allocation request may not succeed if there are no active reservations in
the system at that instant.
Therefore, making a reservation (by calling hugetlb_reserve_pages())
associated with the allocation will ensure that our request would not fail
due to lack of reservations. This will also ensure that proper
region/subpool accounting is done with our allocation.
This patch (of 3):
Currently, hugetlb_reserve_pages() returns a bool to indicate whether the
reservation map update for the range [from, to] was successful or not.
This is not sufficient for the case where the caller needs to determine
how many entries were updated for the range.
Therefore, have hugetlb_reserve_pages() return the number of entries
updated in the reservation map associated with the range [from, to].
Also, update the callers of hugetlb_reserve_pages() to handle the new
return value.
Link: https://lkml.kernel.org/r/20250618053415.1036185-1-vivek.kasireddy@intel.com
Link: https://lkml.kernel.org/r/20250618053415.1036185-2-vivek.kasireddy@intel.com
Signed-off-by: Vivek Kasireddy <vivek.kasireddy@intel.com>
Cc: Steve Sistare <steven.sistare@oracle.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: David Hildenbrand <david@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'fs/hugetlbfs')
| -rw-r--r-- | fs/hugetlbfs/inode.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c index e4de5425838d..00b2d1a032fd 100644 --- a/fs/hugetlbfs/inode.c +++ b/fs/hugetlbfs/inode.c @@ -150,10 +150,10 @@ static int hugetlbfs_file_mmap(struct file *file, struct vm_area_struct *vma) if (inode->i_flags & S_PRIVATE) vm_flags |= VM_NORESERVE; - if (!hugetlb_reserve_pages(inode, + if (hugetlb_reserve_pages(inode, vma->vm_pgoff >> huge_page_order(h), len >> huge_page_shift(h), vma, - vm_flags)) + vm_flags) < 0) goto out; ret = 0; @@ -1561,9 +1561,9 @@ struct file *hugetlb_file_setup(const char *name, size_t size, inode->i_size = size; clear_nlink(inode); - if (!hugetlb_reserve_pages(inode, 0, + if (hugetlb_reserve_pages(inode, 0, size >> huge_page_shift(hstate_inode(inode)), NULL, - acctflag)) + acctflag) < 0) file = ERR_PTR(-ENOMEM); else file = alloc_file_pseudo(inode, mnt, name, O_RDWR, |