| # links(m, dirs) = m3, files0[m] = mkfile(m1, md0, m3, content), files[m] = mkfile(m0, md1, m3, content0), n0 * VFS_PAGE_SIZE < m2, afs-cons(dirs, files), afs-cons(dirs, files0), dcache-cons(dcache, dirs, files), dcache-cons(dcache, dirs, files0), icache-cons(icache, dirs, files), icache-cons(icache, dirs, files0), pcache-cons(pcache, dirs, files), pcache-cons(pcache0, dirs, files0), synced(dirs, icache, pcache), synced(dirs, icache, pcache0), m ∈ files, m ∈ files0 ⊦ ⟪/* (fsync-pages-overwrite : invariant afs-cons(dirs, files) ∧ pcache-cons(pcache, dirs, files) ∧ getinode(m, dirs, files) = getinode(m, dirs, files`) ∧ m = mkinode(m, md, false, # links(m, dirs), 0, m2).ino ∧ m ∈ files ∧ (∀ key. (key ∈ pcache ↔ key ∈ pcache`) ∧ pcache[key].page = (pcache`)[key].page ∧ (pcache[key].dirty → (pcache`)[key].dirty)) ∧ ( ESUCCESS = ESUCCESS → (∀ pageno. (pageno < n0 ⊃ (pageno ∈ files[m].content ↔ pageno ∈ (files` ⊕ pcache`)[m].content) ∧ files[m].content[pageno] = (files` ⊕ pcache`)[m].content[pageno] ;(pageno ∈ files[m].content ↔ pageno ∈ (files`)[m].content) ∧ files[m].content[pageno] = (files`)[m].content[pageno] )))) */; err := ESUCCESS; pcache_check_page#(m, n0, pcache; asynced0, asynced, err); n := n0; inode := mkinode(m, md, false, # links(m, dirs), 0, m2); if asynced0 ∧ asynced then let buf = ? in {pcache_get#(m, n, pcache; asynced0, buf, err); if err = ESUCCESS then afs_writepage#(inode, n, buf, dirs; err, files; asynced1); if err = ESUCCESS then afs_check_commit#(dirs, files; err; asynced1); if err = ESUCCESS then {asynced := false; pcache_set_status#(m, n, asynced; err, pcache)}}; n := n + 1⟫ ( icache-cons(icache, dirs, files) ∧ dcache-cons(dcache, dirs, files) ∧ pcache-cons(pcache, dirs, files) ∧ synced(dirs, icache, pcache) ∧ afs-cons(dirs, files) ∧ m ∈ files ∧ # links(m, dirs) = files[m].nlink ∧ inode.size + VFS_PAGE_SIZE - n * VFS_PAGE_SIZE < inode.size + VFS_PAGE_SIZE - n0 * VFS_PAGE_SIZE) |
files[m] = mkfile(m0, md1, # links(m, dirs), content0), files0[m] = mkfile(m1, md0, # links(m, dirs), content), n0 * VFS_PAGE_SIZE < m2, afs-cons(dirs, files0), afs-cons(dirs, files), dcache-cons(dcache, dirs, files0), dcache-cons(dcache, dirs, files), icache-cons(icache, dirs, files0), icache-cons(icache, dirs, files), pcache-cons(pcache0, dirs, files0), pcache-cons(pcache, dirs, files), synced(dirs, icache, pcache0), synced(dirs, icache, pcache), m ∈ files0, m ∈ files ⊦ ⟪/* (fsync-pages-overwrite : invariant afs-cons(dirs, files) ∧ pcache-cons(pcache, dirs, files) ∧ getinode(m, dirs, files) = getinode(m, dirs, files`) ∧ m = mkinode(m, md, false, # links(m, dirs), 0, m2).ino ∧ m ∈ files ∧ (∀ key. (key ∈ pcache ↔ key ∈ pcache`) ∧ pcache[key].page = (pcache`)[key].page ∧ (pcache[key].dirty → (pcache`)[key].dirty)) ∧ ( ESUCCESS = ESUCCESS → (∀ pageno. (pageno < n0 ⊃ (pageno ∈ files[m].content ↔ pageno ∈ (files` ⊕ pcache`)[m].content) ∧ files[m].content[pageno] = (files` ⊕ pcache`)[m].content[pageno] ;(pageno ∈ files[m].content ↔ pageno ∈ (files`)[m].content) ∧ files[m].content[pageno] = (files`)[m].content[pageno] )))) */; err := ESUCCESS; pcache_check_page#(m, n0, pcache; asynced0, asynced, err); n := n0; inode := mkinode(m, md, false, # links(m, dirs), 0, m2); if asynced0 ∧ asynced then let buf = ? in {pcache_get#(m, n, pcache; asynced0, buf, err); if err = ESUCCESS then afs_writepage#(inode, n, buf, dirs; err, files; asynced1); if err = ESUCCESS then afs_check_commit#(dirs, files; err; asynced1); if err = ESUCCESS then {asynced := false; pcache_set_status#(m, n, asynced; err, pcache)}}; n := n + 1⟫ ( icache-cons(icache, dirs, files) ∧ dcache-cons(dcache, dirs, files) ∧ pcache-cons(pcache, dirs, files) ∧ synced(dirs, icache, pcache) ∧ afs-cons(dirs, files) ∧ m ∈ files ∧ # links(m, dirs) = files[m].nlink ∧ inode.size + VFS_PAGE_SIZE - n * VFS_PAGE_SIZE < inode.size + VFS_PAGE_SIZE - n0 * VFS_PAGE_SIZE)