From patchwork Tue Feb 22 05:40:23 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Suren Baghdasaryan X-Patchwork-Id: 12754554 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 97419C433F5 for ; Tue, 22 Feb 2022 05:40:32 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id A3F918D0002; Tue, 22 Feb 2022 00:40:31 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 9EF708D0001; Tue, 22 Feb 2022 00:40:31 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 890B58D0002; Tue, 22 Feb 2022 00:40:31 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0240.hostedemail.com [216.40.44.240]) by kanga.kvack.org (Postfix) with ESMTP id 7753D8D0001 for ; Tue, 22 Feb 2022 00:40:31 -0500 (EST) Received: from smtpin16.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 24E509F32A for ; Tue, 22 Feb 2022 05:40:31 +0000 (UTC) X-FDA: 79169315862.16.81666A6 Received: from mail-yw1-f201.google.com (mail-yw1-f201.google.com [209.85.128.201]) by imf14.hostedemail.com (Postfix) with ESMTP id 8704B100002 for ; Tue, 22 Feb 2022 05:40:30 +0000 (UTC) Received: by mail-yw1-f201.google.com with SMTP id 00721157ae682-2d6b40fc9bdso124075357b3.13 for ; Mon, 21 Feb 2022 21:40:30 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:message-id:mime-version:subject:from:to:cc; bh=PyCoBTuVnCCgGWzJAr27O1YS5hZPDa+2/ZY9Qp3jx0E=; b=pVKsN6uoJTTW7d5y8Ow04h/N2xLRfXbsytaoZFLAt8NkNYe7iJtrunlLWlWG5P41aw ujQ0w+u+kPlxSmHslv7fpyOCFHkz0aChiaFWxHbL9Y7kqWmrEOM9hbRaCeWJt0jFx/w6 STF9z7phyPLci+0jpEwvu24alh4xnHih95HMhT2u3N0S4A7zG2ra47psdruVAjnaQeq3 d497aGHv5vCowQ7010K//43nQqMjkl7QAxI5FqNhMct1BRW5jDLDRQLMlu1iJ86n8qW8 lKqtxWWknh5LkFlfMmvxgAOIKVAkEpHZ33k2u/oBTIhJa3R6hb6Q6M78Ljc9VNdbT/Hz KNzg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:message-id:mime-version:subject:from:to:cc; bh=PyCoBTuVnCCgGWzJAr27O1YS5hZPDa+2/ZY9Qp3jx0E=; b=ZnkuujofJop4P06YH0udOMc0UmXcJxFkbkNyoa1PQWGK8RUky1dwi2tu6Gj9uoHYYF VcggBQzpUwUp0McdaXgmtlAFoTSQ3z5NDWvVZ/aVLOBICp0MlEAh3pKHInNO63bKTB8P mM9oBVV0mefkelZlpymqheZooAfZIhA2MKNbPrkqPHWWLxN/9rICWsZxzHyPgjpmPSKR n3w38V8RqD84JD5uIGs0JZA5xQwyIGTThI4VfEUmA3sYf3H7KPvvcg+SQ7PFYIKVxDiR rVxF1jR7a5psVyf1OcbhqWA55eYC2fh2VTGbdgaBGDLiOy1bcmQU211JgKrZO8x8ZVpx pFuA== X-Gm-Message-State: AOAM531IXMjEJ2QiyW5QqhgruduES4nu724GKCL6+YJhQW2Gofp4SHjv 0Pw/bICCrHFrMQ+gLPfyMAlDOo7stxw= X-Google-Smtp-Source: ABdhPJzusLduYMb9MkqGSwaYKTlX17vUZOdoY4+DW5HRT6s3+1UAWAMN6c0idnPvIpH1ahiC7JQXwoekXzI= X-Received: from surenb-desktop.mtv.corp.google.com ([2620:15c:211:200:79c1:8a4c:5d17:670f]) (user=surenb job=sendgmr) by 2002:a81:120d:0:b0:2d7:7e79:e298 with SMTP id 13-20020a81120d000000b002d77e79e298mr4244852yws.346.1645508429807; Mon, 21 Feb 2022 21:40:29 -0800 (PST) Date: Mon, 21 Feb 2022 21:40:23 -0800 Message-Id: <20220222054025.3412898-1-surenb@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.35.1.473.g83b2b277ed-goog Subject: [PATCH 1/3] mm: refactor vm_area_struct::anon_vma_name usage code From: Suren Baghdasaryan To: akpm@linux-foundation.org Cc: ccross@google.com, sumit.semwal@linaro.org, mhocko@suse.com, dave.hansen@intel.com, keescook@chromium.org, willy@infradead.org, kirill.shutemov@linux.intel.com, vbabka@suse.cz, hannes@cmpxchg.org, ebiederm@xmission.com, brauner@kernel.org, legion@kernel.org, ran.xiaokai@zte.com.cn, sashal@kernel.org, chris.hyser@oracle.com, dave@stgolabs.net, pcc@google.com, caoxiaofeng@yulong.com, david@redhat.com, gorcunov@gmail.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, kernel-team@android.com, surenb@google.com X-Rspamd-Queue-Id: 8704B100002 X-Stat-Signature: i56qgtk7g396cuyutgjx49ohhxuq9efw Authentication-Results: imf14.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b=pVKsN6uo; dmarc=pass (policy=reject) header.from=google.com; spf=pass (imf14.hostedemail.com: domain of 3TXcUYgYKCKQWYVIRFKSSKPI.GSQPMRYb-QQOZEGO.SVK@flex--surenb.bounces.google.com designates 209.85.128.201 as permitted sender) smtp.mailfrom=3TXcUYgYKCKQWYVIRFKSSKPI.GSQPMRYb-QQOZEGO.SVK@flex--surenb.bounces.google.com X-Rspam-User: X-Rspamd-Server: rspam11 X-HE-Tag: 1645508430-54223 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Avoid mixing strings and their anon_vma_name referenced pointers by using struct anon_vma_name whenever possible. This simplifies the code and allows easier sharing of anon_vma_name structures when they represent the same name. Suggested-by: Matthew Wilcox Suggested-by: Michal Hocko Signed-off-by: Suren Baghdasaryan --- fs/proc/task_mmu.c | 4 +- include/linux/mm.h | 7 +-- include/linux/mm_inline.h | 75 ++++++++++++++++++---------- include/linux/mm_types.h | 5 +- kernel/sys.c | 18 +++++-- mm/madvise.c | 100 ++++++++++++++++---------------------- mm/mmap.c | 10 ++-- 7 files changed, 118 insertions(+), 101 deletions(-) diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index 6e97ed775074..5bfcf24493ac 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -309,7 +309,7 @@ show_map_vma(struct seq_file *m, struct vm_area_struct *vma) name = arch_vma_name(vma); if (!name) { - const char *anon_name; + struct anon_vma_name *anon_name; if (!mm) { name = "[vdso]"; @@ -330,7 +330,7 @@ show_map_vma(struct seq_file *m, struct vm_area_struct *vma) anon_name = vma_anon_name(vma); if (anon_name) { seq_pad(m, ' '); - seq_printf(m, "[anon:%s]", anon_name); + seq_printf(m, "[anon:%s]", anon_name->name); } } diff --git a/include/linux/mm.h b/include/linux/mm.h index 213cc569b192..5744a3fc4716 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2626,7 +2626,7 @@ static inline int vma_adjust(struct vm_area_struct *vma, unsigned long start, extern struct vm_area_struct *vma_merge(struct mm_struct *, struct vm_area_struct *prev, unsigned long addr, unsigned long end, unsigned long vm_flags, struct anon_vma *, struct file *, pgoff_t, - struct mempolicy *, struct vm_userfaultfd_ctx, const char *); + struct mempolicy *, struct vm_userfaultfd_ctx, struct anon_vma_name *); extern struct anon_vma *find_mergeable_anon_vma(struct vm_area_struct *); extern int __split_vma(struct mm_struct *, struct vm_area_struct *, unsigned long addr, int new_below); @@ -3372,11 +3372,12 @@ static inline int seal_check_future_write(int seals, struct vm_area_struct *vma) #ifdef CONFIG_ANON_VMA_NAME int madvise_set_anon_name(struct mm_struct *mm, unsigned long start, - unsigned long len_in, const char *name); + unsigned long len_in, + struct anon_vma_name *anon_name); #else static inline int madvise_set_anon_name(struct mm_struct *mm, unsigned long start, - unsigned long len_in, const char *name) { + unsigned long len_in, struct anon_vma_name *anon_name) { return 0; } #endif diff --git a/include/linux/mm_inline.h b/include/linux/mm_inline.h index b725839dfe71..70b619442d56 100644 --- a/include/linux/mm_inline.h +++ b/include/linux/mm_inline.h @@ -140,50 +140,73 @@ static __always_inline void del_page_from_lru_list(struct page *page, #ifdef CONFIG_ANON_VMA_NAME /* - * mmap_lock should be read-locked when calling vma_anon_name() and while using - * the returned pointer. + * mmap_lock should be read-locked when calling vma_anon_name(). Caller should + * either keep holding the lock while using the returned pointer or it should + * raise anon_vma_name refcount before releasing the lock. */ -extern const char *vma_anon_name(struct vm_area_struct *vma); +extern struct anon_vma_name *vma_anon_name(struct vm_area_struct *vma); +extern struct anon_vma_name *anon_vma_name_alloc(const char *name); -/* - * mmap_lock should be read-locked for orig_vma->vm_mm. - * mmap_lock should be write-locked for new_vma->vm_mm or new_vma should be - * isolated. - */ -extern void dup_vma_anon_name(struct vm_area_struct *orig_vma, - struct vm_area_struct *new_vma); +/* mmap_lock should be read-locked */ +static inline void anon_vma_name_get(struct anon_vma_name *anon_name) +{ + if (anon_name) + kref_get(&anon_name->kref); +} -/* - * mmap_lock should be write-locked or vma should have been isolated under - * write-locked mmap_lock protection. - */ -extern void free_vma_anon_name(struct vm_area_struct *vma); +extern void anon_vma_name_put(struct anon_vma_name *anon_name); -/* mmap_lock should be read-locked */ -static inline bool is_same_vma_anon_name(struct vm_area_struct *vma, - const char *name) +static inline void dup_vma_anon_name(struct vm_area_struct *orig_vma, + struct vm_area_struct *new_vma) { - const char *vma_name = vma_anon_name(vma); + struct anon_vma_name *anon_name = vma_anon_name(orig_vma); - /* either both NULL, or pointers to same string */ - if (vma_name == name) + if (anon_name) { + anon_vma_name_get(anon_name); + new_vma->anon_name = anon_name; + } +} + +static inline void free_vma_anon_name(struct vm_area_struct *vma) +{ + /* Can't use vma_anon_name because vma->vm_mm might not be held */ + if (!vma->vm_file) + anon_vma_name_put(vma->anon_name); +} + +static inline bool anon_vma_name_eq(struct anon_vma_name *anon_name1, + struct anon_vma_name *anon_name2) +{ + if (anon_name1 == anon_name2) return true; - return name && vma_name && !strcmp(name, vma_name); + return anon_name1 && anon_name2 && + !strcmp(anon_name1->name, anon_name2->name); } + #else /* CONFIG_ANON_VMA_NAME */ -static inline const char *vma_anon_name(struct vm_area_struct *vma) +static inline struct anon_vma_name *vma_anon_name(struct vm_area_struct *vma) { return NULL; } + +static inline struct anon_vma_name *anon_vma_name_alloc(const char *name) +{ + return NULL; +} + +static inline void anon_vma_name_get(struct anon_vma_name *anon_name) {} +static inline void anon_vma_name_put(struct anon_vma_name *anon_name) {} static inline void dup_vma_anon_name(struct vm_area_struct *orig_vma, - struct vm_area_struct *new_vma) {} + struct vm_area_struct *new_vma) {} static inline void free_vma_anon_name(struct vm_area_struct *vma) {} -static inline bool is_same_vma_anon_name(struct vm_area_struct *vma, - const char *name) + +static inline bool anon_vma_name_eq(struct anon_vma_name *anon_name1, + struct anon_vma_name *anon_name2) { return true; } + #endif /* CONFIG_ANON_VMA_NAME */ static inline void init_tlb_flush_pending(struct mm_struct *mm) diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 5140e5feb486..1d298ff2e1d0 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -416,7 +416,10 @@ struct vm_area_struct { struct rb_node rb; unsigned long rb_subtree_last; } shared; - /* Serialized by mmap_sem. */ + /* + * Serialized by mmap_sem. Never use directly because it is + * valid only when vm_file is NULL. Use vma_anon_name instead. + */ struct anon_vma_name *anon_name; }; diff --git a/kernel/sys.c b/kernel/sys.c index ecc4cf019242..60c3f9eac9eb 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -7,6 +7,7 @@ #include #include +#include #include #include #include @@ -2278,15 +2279,16 @@ static int prctl_set_vma(unsigned long opt, unsigned long addr, { struct mm_struct *mm = current->mm; const char __user *uname; - char *name, *pch; + struct anon_vma_name *anon_name; int error; switch (opt) { case PR_SET_VMA_ANON_NAME: uname = (const char __user *)arg; if (uname) { - name = strndup_user(uname, ANON_VMA_NAME_MAX_LEN); + char *name, *pch; + name = strndup_user(uname, ANON_VMA_NAME_MAX_LEN); if (IS_ERR(name)) return PTR_ERR(name); @@ -2296,15 +2298,21 @@ static int prctl_set_vma(unsigned long opt, unsigned long addr, return -EINVAL; } } + /* anon_vma has its own copy */ + anon_name = anon_vma_name_alloc(name); + kfree(name); + if (!anon_name) + return -ENOMEM; + } else { /* Reset the name */ - name = NULL; + anon_name = NULL; } mmap_write_lock(mm); - error = madvise_set_anon_name(mm, addr, size, name); + error = madvise_set_anon_name(mm, addr, size, anon_name); mmap_write_unlock(mm); - kfree(name); + anon_vma_name_put(anon_name); break; default: error = -EINVAL; diff --git a/mm/madvise.c b/mm/madvise.c index 5604064df464..f81d62d8ce9b 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -65,11 +65,14 @@ static int madvise_need_mmap_write(int behavior) } #ifdef CONFIG_ANON_VMA_NAME -static struct anon_vma_name *anon_vma_name_alloc(const char *name) +struct anon_vma_name *anon_vma_name_alloc(const char *name) { struct anon_vma_name *anon_name; size_t count; + if (!name) + return NULL; + /* Add 1 for NUL terminator at the end of the anon_name->name */ count = strlen(name) + 1; anon_name = kmalloc(struct_size(anon_name, name, count), GFP_KERNEL); @@ -81,78 +84,55 @@ static struct anon_vma_name *anon_vma_name_alloc(const char *name) return anon_name; } -static void vma_anon_name_free(struct kref *kref) +struct anon_vma_name *vma_anon_name(struct vm_area_struct *vma) { - struct anon_vma_name *anon_name = - container_of(kref, struct anon_vma_name, kref); - kfree(anon_name); -} - -static inline bool has_vma_anon_name(struct vm_area_struct *vma) -{ - return !vma->vm_file && vma->anon_name; -} + mmap_assert_locked(vma->vm_mm); -const char *vma_anon_name(struct vm_area_struct *vma) -{ - if (!has_vma_anon_name(vma)) + if (vma->vm_file) return NULL; - mmap_assert_locked(vma->vm_mm); - - return vma->anon_name->name; + return vma->anon_name; } -void dup_vma_anon_name(struct vm_area_struct *orig_vma, - struct vm_area_struct *new_vma) +static void vma_anon_name_free(struct kref *kref) { - if (!has_vma_anon_name(orig_vma)) - return; - - kref_get(&orig_vma->anon_name->kref); - new_vma->anon_name = orig_vma->anon_name; + struct anon_vma_name *anon_name = + container_of(kref, struct anon_vma_name, kref); + kfree(anon_name); } -void free_vma_anon_name(struct vm_area_struct *vma) +void anon_vma_name_put(struct anon_vma_name *anon_name) { - struct anon_vma_name *anon_name; - - if (!has_vma_anon_name(vma)) - return; - - anon_name = vma->anon_name; - vma->anon_name = NULL; - kref_put(&anon_name->kref, vma_anon_name_free); + if (anon_name) + kref_put(&anon_name->kref, vma_anon_name_free); } /* mmap_lock should be write-locked */ -static int replace_vma_anon_name(struct vm_area_struct *vma, const char *name) +static int replace_vma_anon_name(struct vm_area_struct *vma, + struct anon_vma_name *anon_name) { - const char *anon_name; + struct anon_vma_name *orig_name = vma_anon_name(vma); - if (!name) { - free_vma_anon_name(vma); + if (!anon_name) { + vma->anon_name = NULL; + anon_vma_name_put(orig_name); return 0; } - anon_name = vma_anon_name(vma); - if (anon_name) { - /* Same name, nothing to do here */ - if (!strcmp(name, anon_name)) - return 0; + if (anon_vma_name_eq(orig_name, anon_name)) + return 0; - free_vma_anon_name(vma); - } - vma->anon_name = anon_vma_name_alloc(name); - if (!vma->anon_name) - return -ENOMEM; + anon_vma_name_get(anon_name); + vma->anon_name = anon_name; + anon_vma_name_put(orig_name); return 0; } #else /* CONFIG_ANON_VMA_NAME */ -static int replace_vma_anon_name(struct vm_area_struct *vma, const char *name) +static int replace_vma_anon_name(struct vm_area_struct *vma, + struct anon_vma_name *anon_name) { - if (name) + if (anon_name) return -EINVAL; return 0; @@ -165,13 +145,13 @@ static int replace_vma_anon_name(struct vm_area_struct *vma, const char *name) static int madvise_update_vma(struct vm_area_struct *vma, struct vm_area_struct **prev, unsigned long start, unsigned long end, unsigned long new_flags, - const char *name) + struct anon_vma_name *anon_name) { struct mm_struct *mm = vma->vm_mm; int error; pgoff_t pgoff; - if (new_flags == vma->vm_flags && is_same_vma_anon_name(vma, name)) { + if (new_flags == vma->vm_flags && anon_vma_name_eq(vma_anon_name(vma), anon_name)) { *prev = vma; return 0; } @@ -179,7 +159,7 @@ static int madvise_update_vma(struct vm_area_struct *vma, pgoff = vma->vm_pgoff + ((start - vma->vm_start) >> PAGE_SHIFT); *prev = vma_merge(mm, *prev, start, end, new_flags, vma->anon_vma, vma->vm_file, pgoff, vma_policy(vma), - vma->vm_userfaultfd_ctx, name); + vma->vm_userfaultfd_ctx, anon_name); if (*prev) { vma = *prev; goto success; @@ -209,7 +189,7 @@ static int madvise_update_vma(struct vm_area_struct *vma, */ vma->vm_flags = new_flags; if (!vma->vm_file) { - error = replace_vma_anon_name(vma, name); + error = replace_vma_anon_name(vma, anon_name); if (error) return error; } @@ -976,6 +956,7 @@ static int madvise_vma_behavior(struct vm_area_struct *vma, { int error; unsigned long new_flags = vma->vm_flags; + struct anon_vma_name *anon_name; switch (behavior) { case MADV_REMOVE: @@ -1040,8 +1021,9 @@ static int madvise_vma_behavior(struct vm_area_struct *vma, break; } + anon_name = vma_anon_name(vma); error = madvise_update_vma(vma, prev, start, end, new_flags, - vma_anon_name(vma)); + anon_name); out: /* @@ -1225,7 +1207,7 @@ int madvise_walk_vmas(struct mm_struct *mm, unsigned long start, static int madvise_vma_anon_name(struct vm_area_struct *vma, struct vm_area_struct **prev, unsigned long start, unsigned long end, - unsigned long name) + unsigned long anon_name) { int error; @@ -1234,7 +1216,7 @@ static int madvise_vma_anon_name(struct vm_area_struct *vma, return -EBADF; error = madvise_update_vma(vma, prev, start, end, vma->vm_flags, - (const char *)name); + (struct anon_vma_name *)anon_name); /* * madvise() returns EAGAIN if kernel resources, such as @@ -1246,7 +1228,7 @@ static int madvise_vma_anon_name(struct vm_area_struct *vma, } int madvise_set_anon_name(struct mm_struct *mm, unsigned long start, - unsigned long len_in, const char *name) + unsigned long len_in, struct anon_vma_name *anon_name) { unsigned long end; unsigned long len; @@ -1266,8 +1248,8 @@ int madvise_set_anon_name(struct mm_struct *mm, unsigned long start, if (end == start) return 0; - return madvise_walk_vmas(mm, start, end, (unsigned long)name, - madvise_vma_anon_name); + return madvise_walk_vmas(mm, start, end, (unsigned long)anon_name, + madvise_vma_anon_name); } #endif /* CONFIG_ANON_VMA_NAME */ /* diff --git a/mm/mmap.c b/mm/mmap.c index 1e8fdb0b51ed..80d2ae204a98 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1031,7 +1031,7 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start, static inline int is_mergeable_vma(struct vm_area_struct *vma, struct file *file, unsigned long vm_flags, struct vm_userfaultfd_ctx vm_userfaultfd_ctx, - const char *anon_name) + struct anon_vma_name *anon_name) { /* * VM_SOFTDIRTY should not prevent from VMA merging, if we @@ -1049,7 +1049,7 @@ static inline int is_mergeable_vma(struct vm_area_struct *vma, return 0; if (!is_mergeable_vm_userfaultfd_ctx(vma, vm_userfaultfd_ctx)) return 0; - if (!is_same_vma_anon_name(vma, anon_name)) + if (!anon_vma_name_eq(vma_anon_name(vma), anon_name)) return 0; return 1; } @@ -1084,7 +1084,7 @@ can_vma_merge_before(struct vm_area_struct *vma, unsigned long vm_flags, struct anon_vma *anon_vma, struct file *file, pgoff_t vm_pgoff, struct vm_userfaultfd_ctx vm_userfaultfd_ctx, - const char *anon_name) + struct anon_vma_name *anon_name) { if (is_mergeable_vma(vma, file, vm_flags, vm_userfaultfd_ctx, anon_name) && is_mergeable_anon_vma(anon_vma, vma->anon_vma, vma)) { @@ -1106,7 +1106,7 @@ can_vma_merge_after(struct vm_area_struct *vma, unsigned long vm_flags, struct anon_vma *anon_vma, struct file *file, pgoff_t vm_pgoff, struct vm_userfaultfd_ctx vm_userfaultfd_ctx, - const char *anon_name) + struct anon_vma_name *anon_name) { if (is_mergeable_vma(vma, file, vm_flags, vm_userfaultfd_ctx, anon_name) && is_mergeable_anon_vma(anon_vma, vma->anon_vma, vma)) { @@ -1167,7 +1167,7 @@ struct vm_area_struct *vma_merge(struct mm_struct *mm, struct anon_vma *anon_vma, struct file *file, pgoff_t pgoff, struct mempolicy *policy, struct vm_userfaultfd_ctx vm_userfaultfd_ctx, - const char *anon_name) + struct anon_vma_name *anon_name) { pgoff_t pglen = (end - addr) >> PAGE_SHIFT; struct vm_area_struct *area, *next;